Examining COVID-19-Related Changes toward More Climate-Friendly Food Consumption in Germany

Abstract

The present study examined the overall potential that the COVID-19 pandemic and its restrictions have for the promotion of climate-friendly food consumption in Germany. We looked at COVID-19-related changes in people’s climate-friendly food-consumption behaviors by comparing retrospectively self-reported performances between the time period in which the COVID-19 restrictions were in place and the pre-COVID-19 period. Furthermore, we examined the durability of such COVID-19-related changes with regard to an imagined post-COVID-19 period and the role of people’s personal climate-protection norms in COVID-19-related behavioral changes. To do so, we conducted two online surveys in June/July 2020 with German consumers: (a) an online study in a sample that was representative of the German population (NCOR1 = 3092) and (b) another online study in a smaller sample of German consumers (NCOR2 = 300). Altogether, the data from both surveys indicated several COVID-19-related changes toward more climate-friendly food consumption, not only during the COVID-19 pandemic and its restrictions, but also with regard to long-term changes in a potential post-COVID-19 period. Furthermore, our results also provide initial empirical evidence that people’s personal climate-protection norms are relevant moderating factors of these short- and long-term COVID-19-related behavioral changes.

1. Introduction

1.1. The COVID-19 Pandemic around the World and in Germany

Apart from all the relevant consequences for health and economics, the COVID-19 pandemic and the political restrictions implemented by governments around the globe to limit the spread of the virus have also had extensive consequences for societies. However, these restrictions can also represent windows of opportunity that may allow desirable changes to be made to modern society—especially with regard to the promotion of sustainability and climate protection. In this context, there is initial empirical evidence that COVID-19 may offer a window of opportunity for the promotion of sustainable (behavioral) changes, with regard, for example, to changes in people’s daily commutes and travel mobility in Germany (see, e.g., [1,2]). Previous research has demonstrated that the pandemic and its restrictions have affected people’s daily (transport mode) choices by changing the external factors of their (mobility) behavior. These changes can result in a disruption and a subsequent dismantling of people’s generally very stable (mobility) habits (see, e.g., [3]). Apart from the mobility sector, the pandemic probably also affects the external factors of various other behavioral domains and daily consumption patterns, which are relevant for sustainability and global climate protection as well (e.g., people’s daily food-consumption patterns).

1.2. Changes in (Climate-Friendly) Food Consumption in Response to COVID-19 Restrictions

Household food consumption, particularly in high-income countries, is responsible for more than 60% of global GHG emissions [4] with, for example, people’s consumption of meat and animal-based products producing 14.5% of global GHG emissions [5]. This is why a crucial challenge for global climate protection involves changing the present dietary patterns of individuals to more climate-friendly food-consumption patterns [6,7].

With regard to the COVID-19-related changes in people’s daily lives, some changes directly affect people’s daily food-consumption patterns. For example, during the lockdowns restaurants and cafeterias were closed. Simultaneously, people spent more time at home because many worked remotely. As a consequence, during the lockdowns more people prepared their own meals than before the pandemic (see, e.g., [8]). Additionally, panic buying and stockpiling in response to COVID-19 and its restrictions, especially during the first lockdowns, also represented relevant consequences of the pandemic with regard to people’s food-consumption patterns (see, e.g., [9,10,11]).

Previous studies have provided a great deal of empirical evidence that COVID-19 and its restrictions have initiated some changes in people’s food-consumption patterns. For example, referring to results of an online survey conducted in the USA, Jaeger et al. [12] provided empirical evidence that the pandemic can be a catalyst for positive dietary change toward more healthy diets, especially if consumers place great importance on health as a motive of their daily decisions about their food consumption (see, e.g., [13,14,15] for further examples). In contrast, Marty et al. [16] provided empirical evidence that, in France, the nutritional quality of people’s diets was lower during the lockdowns compared with before. Thus, it has to be mentioned that in this study people’s relevant food-choice motives were also shown to be important factors of influence for changes in the nutritional quality of people’s diets during the lockdowns.

Furthermore, some previous studies have provided initial empirical evidence for the effects of the pandemic, especially on people’s climate-friendly food-consumption patterns. For example, in a German online survey, the participants reported reduced meat consumption as well as reduced consumption of ready-made meals during the lockdowns [17]. With respect to the reductions in meat consumption during lockdowns in particular, there is a lot of corresponding empirical evidence from diverse studies and countries (see, e.g., [13,18,19]). Considering other types of climate-friendly food consumption, the empirical findings seem to be more ambiguous. For example, regarding household food waste, Rodgers et al. (2021) provided empirical evidence of reduced amounts of household food waste during lockdowns in Italy and America, as did Amicarelli et al. [20] and Principato et al. [21]. By contrast, the empirical results provided by Filimonau et al. [22] implied potentially higher amounts of food waste in England due to increases in the number of people buying food for themselves and cooking at home. With regard to the consumption of organic food, there is strong empirical evidence of increased consumption of organic food during the pandemic—mostly assumed to be based on increases in the motivation to choose a healthy diet (see, e.g., [23] for an overview).

Taken together, the previous results clearly imply that the pandemic and its restrictions have significantly affected people’s daily food-consumption patterns around the world. With regard to COVID-19-related changes toward more climate-friendly food consumption (e.g., by reducing the consumption of meat and dairy products and by decreasing household food waste), some of the empirical results remain heterogeneous.

1.3. Effects of People’s Motivation to Protect the Climate on COVID-19-Related Changes toward More Climate-Friendly Food Consumption

Although, as mentioned above, there is a lot of empirical evidence that COVID-19 and its restrictions have initiated some changes in people’s daily food-consumption patterns as well as changes toward more climate-friendly food consumption, more research examining the psychological predictors of such COVID-19-related behavioral changes is (still) needed—especially with respect to the psychological predictors of COVID-19-related changes toward more climate-friendly food consumption. Considering the psychological predictors of COVID-19-related changes in people’s daily food-consumption patterns in general, many studies have investigated the relevant factors of influence. Thus, these studies comprehensively imply that people’s motivations to adopt healthy diets or people’s perceptions of health risks are relevant predictors of changes in their daily food-consumption patterns during the pandemic (see, e.g., [12]). By contrast, there are only a few studies that have specifically examined the psychological predictors of COVID-19-related changes toward more climate-friendly food consumption. The empirical results of a study conducted by Li et al. [24] with a sample of Chinese consumers found that consumers’ food security and their financial and health risk perceptions were relevant predictors of their sustainable food-purchasing and consumption behaviors. Furthermore, Hempel and Roosen [25] provided initial empirical evidence for a significant positive relation between consumers’ internal locus of control and their intention to purchase local food, while there were no relations found for consumer purchase decisions on organic food. Nonetheless, there has been a lack of studies that have explicitly examined the effects of people’s climate-protection motivation on COVID-19-related changes toward more climate-friendly food consumption.

However, on the basis of previous psychological research on the relevant psychological predictors of consumers’ climate-friendly behavioral changes in general (see, e.g., [26] for an overview), some assumptions can be deduced. Among other findings, there is extensive (environmental) psychological research that has provided strong empirical evidence that people’s personal norms for climate protection (i.e., strong feelings of a moral obligation to protect the climate) are important predictors of consumers’ climate-friendly behavior changes (see, e.g., [27] for an overview).

Furthermore, as implied by the empirical findings described above, it should be mentioned that the pandemic and its restrictions strongly affected people’s daily food/meal consumption patterns by changing relevant external/situational factors of their food-consumption behavior. Consequently, these changes can result in the weakening or even in the breaking-up of peoples’ very stable food-consumption habits (see, e.g., [28,29,30]). As such stable habits typically suppress reflected behavioral decision processes, the behavioral effects of normative predictors such as people’s personal norms for climate protection are often eliminated under conditions of strong habitualization (see, e.g., [31,32]). In this context, previous research showed that stable habits can be “broken up” by strong changes of external/ situational factors, under which people make behavioral choices. Consequently, such a breaking-up process of habits can result in more reflected behavioral decisions, which can finally be affected, for example, by peoples’ personal norms for climate protection (e.g., [33]). As the COVID-19 pandemic and its restrictions can be seen as such a strong change of external/situational factors, they can therefore serve as a window of opportunity (see, e.g., [34]) for long-lasting changes towards more climate-friendly food-consumption patterns.

Furthermore, it should also be mentioned that there is considerable evidence for the effects of such strong changes in external/situational factors on the promotion of (long-term) climate-friendly behavioral changes, especially when individuals are already strongly motivated—represented, for example, by their strong personal norms for climate protection—to make such changes. Moreover, if such temporal changes were accompanied by positive experiences (e.g., [35,36]), people’s personal climate-protection norms should be relevant moderating factors of COVID-19-related changes toward more climate-friendly food consumption.

1.4. Research Objectives and Research Hypotheses

Against this background, the present study was guided by several research objectives. Our first research objective was to (further) examine the overall potential that the COVID-19 pandemic and its restrictions have for the promotion of climate-friendly food consumption in Germany. By doing so, we initially explored consumers’ self-perceived COVID-19-related changes in their daily food-consumption patterns as well as in their food-consumption-related beliefs during the time period in which the COVID-19 restrictions were in place in Germany (i.e., from April to June 2020; Research Question RQ1).

Furthermore, we explicitly examined COVID-19-related changes in people’s daily food-consumption patterns by comparing retrospectively self-reported engagement in diverse climate-friendly food-consumption behaviors between the time period when the COVID-19 restrictions were in place and the pre-COVID-19 period (Research Question RQ2). Furthermore, we also explored the durability of such COVID-19-related behavioral changes by examining people’s intended engagement in these diverse climate-friendly food-consumption behaviors in an imagined post-COVID-19 period, again compared with retrospectively self-reported behavioral performances in the pre-COVID-19 period (Research Question RQ3).

Finally, we examined the role of people’s personal climate-protection norms on COVID-19-related changes toward more climate-friendly food consumption and in their durability with regard to a post-COVID-19 period. Based on previous research on the effects of such norms for the promotion of climate-friendly (food) consumption (see Section 1.3 for details), the following research hypotheses were tested:

Hypothesis 1 (H1).

People’s personal climate-protection norms are significant moderators of changes toward more climate-friendly food consumption during the time period in which the COVID-19 restrictions were in place compared with the pre-COVID-19 period.

Hypothesis 2 (H2).

People’s personal climate-protection norms are significant moderators of people’s long-term changes toward more climate-friendly food consumption in an imagined post-COVID-19 period compared with the pre-COVID-19 period.

2. Materials and Methods

2.1. Data Collection and Studied Samples

The data for the present study were collected in two online surveys administered to German consumers.

The first online survey (i.e., the COR₁ survey) was administered to a large sample of German consumers from the end of June until the middle of July 2020. The survey’s participants were recruited by a national panel-providing company. Altogether, 3357 people completed the COR₁ survey. After the exclusion of unreliable cases on the basis of the participants’ answering time, their answers to some open-ended questions, and missing values, a total of N = 3092 participants formed the final sample of the COR₁ survey. This final sample was representative of the German population with respect to age and gender [37,38,39]. The participants’ ages ranged from 18 to 69 years (M = 44.86, SD = 14.39), and 50.5% of them were female. Household monthly income groups ranged from “less than EUR 900” to “more than EUR 4000” with most participants reporting “EUR 2601 to EUR 4000” (27.7%). For the highest level of education, 37.2% of the participants reported a higher-education entrance qualification, 30.8% secondary education, and 31.5% finished school. As a consequence, the sample was nearly representative of the German population regarding the highest level of education (see

Table 1. Sociodemographic features of the final samples that answered the COR₁ and COR₂ surveys, compared with the German population [37,38,39,40].

		COR1 Survey (N = 3092)	COR2 Survey (N = 300)		German Population
Age		M = 44.86 (SD = 14.39)	M = 51.91 (SD = 16.29)		M = 44.40
Gender	Female	50.5%	51.2%		50.6%
	Male	49.2%	48.8%		49.4%
Highest level of education	Did not complete high school	0.4%	0.5%		4.0%
	Completed high school	31.5%	13.5%		29.6%
	Secondary education	30.8%	36.6%		23.3%
	Higher-education entrance qualification	37.2%	39.9%		32.5%
Income	<EUR 900	7.2%	<EUR 600	3.7	M = EUR 3580
	EUR 900 to EUR 1300	8.0%	EUR 601–EUR 1500	13.3
	EUR 1301 to EUR 1500	5.4%	EUR 1501–EUR 3000	39.3
	EUR 1501 to EUR 2000	9.4%	EUR 3001–EUR 4500	32.0
	EUR 2001 to EUR 2600	14.4%	EUR 4501–EUR 6000	8.7
	EUR 2601 to EUR 4000	27.7%	>EUR 6000	3.0
	>EUR 4000	28%
Size of household	1	21.2	21.9		42.3
	2	39.9	41.8		33.2
	3	19.6	19.1		11.9
	4	14.1	17.2 (4 and more)		9.1
	5 or more	5.2			3.5

for details). Household size ranged from “one” to “more than five” household members, with two household members most often reported by the participants (39.9%).

The second online survey (i.e., the COR₂ survey) was administered in July 2020 to another sample of German consumers. The survey’s participants were also recruited by a national panel-providing company. A total of N = 300 participants formed the final sample of the COR₂ survey. The participants’ ages ranged from 18 to 86 years (M = 55.91, SD = 16.29), and 51.2% of them were female. Household monthly income groups ranged from “less than EUR 600” to “more than EUR 6000” with most participants reporting “EUR 1501 to EUR 3000” (39.3%). For the highest level of education, 39.9% of the participants reported a higher-education entrance qualification, 36.6% secondary education, and 13.5% finished school. Household size ranged from “one” to “more than four”, with two household members most often reported by the participants (41.8%). With regard to gender, the COR₂ survey’s sample was (nearly) representative of the German population (see Table 1 for details).

2.2. Procedure and Measures

Although there were some differences with regard to the items/scales used per survey (see Section 2.2.2 for details), the data-acquisition procedures were comparable for the COR₁ and COR₂ surveys (see

Table A1. Scales/items used in the COR₁ and COR₂ surveys.

Variable	Used in…	Number of Items	Items	Answer Options
Self-perceptions of COVID-19-related changes in participants’ daily food-consumption patterns during the period in which the COVID-19 restrictions were in place	COR1 and COR2	5	Please think about the last three months. How much do you agree with the following statements? During the last three months … ... I spend more time planning and preparing my meals and grocery shopping than usual. … my cooking skills have improved. … I have tried many new dishes and/or new ingredients in my meals. … I have learned to use leftovers from my meals sensibly instead of throwing them away. … I ate out less often or got take-out from restaurants, cafeterias, canteens, or similar.	Completely disagree (1) to completely agree (7), I don’t know
Self-perceptions of COVID-19-related changes in participants’ food-consumption-related beliefs during the period in which the COVID-19 restrictions were in place	COR1 and COR2	5	Please think about the last three months. How much do you agree with the following statements? On the basis of my experiences in the last three months … … my cooking and eating habits have changed overall. … I have focused on my own diet more overall than before. … I view food as a more valuable resource than before. … I would be willing to pay higher prices for groceries than before. … it has become easier for me to stick with my self-determined diet.	Completely disagree (1) to completely agree (7), I don´t know
Engagement in diverse climate-friendly food-consumption behaviors during the time period in which the COVID-19 restrictions were in place and in the pre-COVID-19 period (a)	COR1	1	Meat consumption: Please think about the last 3 (12) months. How often did you consume meat in your main meal?	daily; six times a week; four to five times a week; two to three times a week; once a week or less; never
		1	Consumption of organic food: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought groceries from an establishment that guarantees controlled organic cultivation	Never (1) to always (6), I don´t know
		1	Household food waste: Please think about the last 3 (12) months. How often did you throw food away at home in an average month?	Daily, several times a week, once a week, several times a month, once a month, never, I don’t know
	COR2	3	Meat consumption: Please think about the last 3 (12) months. How often did you consume meat in your main meal? Beef pork poultry	Never (1), one day per week (2) to 6 or 7 days per week (7), I don’t know
	COR2	1	Consumption of organic food: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought groceries from an establishment that guarantees controlled organic cultivation.	Never (1) to always (7), I don´t know
	COR2	1	Household food waste: […] Out of all the foods that you bought per week for your household—please estimate the amount of food that was spoiled and/or thrown out?	Nothing (1), less than 10% (2), 11–20% (3), 21–30% (4), 31–40% (5), 41–50% (6), more than 50% (7), I don’t know
	COR2	1	Consumption of regionally produced food: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought regionally produced food.	Never (1) to always (7), I don´t know
	COR2	1	Consumption of in-season produced food: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought in-season food.	Never (1) to always (7), I don´t know
	COR2	1	Consumption of food with less plastic packaging: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought less plastic packaging.	Never (1) to always (7), I don´t know
	COR2	1	Consumption of ready-made meals: Please think about the last 3 (12) months. How often did you engage in the following activities? I bought ready-made meals.	Never (1), one day per week (2) to 6 or 7 days per week (7), I don´t know
Personal climate-protection norms	COR1 and COR2	3	To what extent do you agree with the following statements? On the basis of my personal values, I feel obligated to engage politically for climate protection. On the basis of my personal values, I feel obligated to contribute to the protection of the climate through my daily behavior. No matter what others expect from me, I feel obligated to contribute to climate protection by changing my lifestyle.	Do not agree at all (1) to completely agree (7), I don´t know

Notes. ^(a) The same items were used for measuring participants’ intended engagement in diverse climate-friendly food-consumption behaviors in an imagined post-COVID-19 period by using the formulation “the next 12 months” to refer to an imagined post-COVID-19 period and by using a 5-point frequency scale for answering (1 = never/nearly never to 5 = every day/nearly every day).

in Appendix B for an overview on all scales/items used per survey). First, the participants’ sociodemographic features were assessed. The participants then provided information about their climate-friendly food-consumption patterns in different time frames (i.e., in the pre-COVID-19 period, during the time period in which the COVID-19 restrictions were in place in Germany, i.e., from April to June 2020; in the pre-COVID-19 period; and in the imagined post-COVID-19 period, i.e., during the next 12 months). Thus, we assessed retrospective and prospective (intended) self-reported engagement in diverse climate-friendly food-consumption behaviors. Then, the participants were asked to report self-perceived changes in their daily food-consumption patterns, as well as in their food-consumption-related beliefs during the period in which the COVID-19 restrictions were in place in Germany. Afterwards, we assessed the participants’ personal climate-protection norms. In the end, the participants were thanked for their participation and given the opportunity to give feedback and ask any remaining questions.

2.2.1. Self-Perceptions of COVID-19-Related Changes during the Period in which the COVID-19 Restrictions Were in Place

In order to capture the participants’ self-perceived changes in their daily food-consumption patterns during the period in which the COVID-19 restrictions were in place in Germany, in both surveys the participants were asked “How much do you agree with the following statements? During the last three months…” with regard to five different statements (e.g., “… I spent more time planning and preparing my meals and grocery shopping than usual”; see Figure 1 or Table A1 in Appendix B for an overview).

Furthermore, we measured the participants’ self-perceived changes in their food-consumption-related beliefs during the period in which the COVID-19 restrictions were in place in Germany. Therefore, we asked the participants “Please think about the last three months. How much do you agree with the following statements? On the basis of my experiences in the last three months …“. The participants indicated their agreement with regard to another five statements (e.g., “… it has become easier for me to make better food choices in my everyday life”; see Figure 2 in Section 3.1 for an overview).

The participants’ agreement with all these items was measured on a 7-point Likert scale (1 = “completely disagree” to 7 = “completely agree”).

2.2.2. Engagement in Diverse Climate-Friendly Food-Consumption Behaviors during the Time Period in which the COVID-19 Restrictions Were in Place and in the Pre-COVID-19 Period

When measuring the participants’ engagement in diverse climate-friendly food-consumption behaviors during the period in which the COVID-19 restrictions were in place, as well as in the pre-COVID-19 period, the behaviors we captured varied across the surveys (see again Table A1 in Appendix B for all details and Appendix A ⁽¹⁾).

With regard to the COR₁ survey, we measured the participants’ self-reported behavioral engagement during the period in which the COVID-19 restrictions were in place (i.e., “the last 3 months”) and in the pre-COVID-19 period (i.e., “the last 12 months”), referring to (a) meat consumption, (b) consumption of organic food, and (c) household food waste.

With regard to the COR₂ survey, we extended this measurement by capturing the participants’ self-reported behavioral engagement during the time period in which the COVID-19 restrictions were in place and in the pre-COVID-19 period, referring to (a) the consumption of different types of meat (i.e., beef, pork, and poultry)—these three items were aggregated into one reliable meat-consumption measure per time frame (during the COVID-19 restrictions: α = 0.61; the pre-COVID-19 period: α = 0.67; the imagined post-COVID-19 period: α = 0.73)—(b) the consumption of organic food; (c) household food waste; (d) the consumption of regionally produced food; (e) the consumption of in-season food; (f) the consumption of food with less plastic packaging; and (g) the consumption of ready-made meals.

2.2.3. Personal Climate-Protection Norms

In line with Schwartz (1975), we measured the participants’ personal climate-protection norms with three items (e.g., “No matter what others expect from me, I feel obligated to contribute to climate protection by changing my lifestyle”; see again Table A1 in Appendix B for an overview) that were introduced with “To what extent do you agree with the following statements?”. These items were answered on a 7-point Likert scale (1 = “do not agree at all” to 7 = “completely agree”). With α_Cor1 = 0.92 and α_Cor2 = 0.93, this scale showed very good reliability (e.g., [41]).

2.2.4. Intended Engagement in Diverse Climate-Friendly Food-Consumption Behaviors in an Imagined Post-COVID-19 Period

The items for measuring the participants’ intended engagement in diverse climate-friendly food-consumption behaviors in an imagined post-COVID-19 period were formulated in parallel with the measures assessing these performances retrospectively for the time period in which the COVID-19 restrictions were in place in Germany and during the pre-COVID-19 period (see Section 2.2.2 for an overview). Thus, we used the term “the next 12 months” to refer to an imagined post-COVID-19 period. Thus, the items were introduced with “Please think about the next 12 months. State how frequently you will ….” (e.g., “consume meat in your main meal”) and were answered on a 5-point frequency scale (e.g., 1 = “never/nearly never” to 5 = “every day/nearly every day”).

2.3. Statistical Analyses

Statistical analyses were conducted using Statistical Package for the Social Sciences (SPSS; version 26). To examine consumers’ self-perceived COVID-19-related changes in their daily food-consumption patterns and their food-consumption-related beliefs (RQ1), we computed descriptive statistics for our measures for both samples (COR₁ and COR₂; see Section 3.1 for the results of these analyses).

With regard to the explicit examination of COVID-19-related changes toward more climate-friendly food consumption (RQ2) as well as with regard to the investigation of the durability of the change (RQ3), we computed t-tests for dependent samples. With these analyses, we compared behavioral performances between the time period in which the COVID-19 restrictions were in place and the pre-COVID-19 period (RQ2) and between the (intended) behavioral performances in the post-COVID-19 period versus the pre-COVID-19 period (RQ3). Such parametric data analyses were not appropriate for analyzing the food waste data in the COR₁ sample (because this dependent variable was measured on an ordinal scale). Therefore, we used Wilcoxon tests to examine the COVID-19-related changes and durability when referring to household food waste (see Section 3.2 and Section 3.3 for the results of these analyses).

To examine the role that people’s personal climate-protection norms played in determining COVID-19-related changes toward more climate-friendly food consumption and for the durability of the change with regard to the post-COVID-19 period, we used a stepwise analytical procedure. In an initial step, we analyzed data from both surveys with regard to the possible linear effects of the participants’ personal norms on COVID-19-related changes toward more climate-friendly food consumption as well as on the durability of the change by computing multiple regression analyses (see Section 3.4.1 for the results of these analyses and see Appendix A ⁽²⁾ for further information).

In a second step, we extended/complemented these correlational analyses with regard to the possible nonlinear interaction effects of the participants’ personal norms by computing one-factor repeated-measures ANCOVAs for nearly all of the self-reported climate-friendly food-consumption measures in the COR₁ and COR₂ data. Thus, we compared the behavioral measures of the participants characterized by high versus low personal climate-protection norms (the participants’ group assignment was based on a median split of this variable) and controlled for the possible effects of the participants’ sociodemographic features (i.e., gender, age, education, and income) by using these variables as covariates within the analyses; see Section 3.4.2 for the results of these analyses).

3. Results

3.1. Consumers’ Self-Perceived COVID-19-Related Changes in Their Daily Food-Consumption Patterns and Their Food-Consumption-Related Beliefs (RQ1)

Overall, referring to both surveys, the results did not show very strong self-perceived changes in the participants’ daily food-consumption patterns and in their food-consumption-related beliefs during the pandemic (see Figure 1 and Figure 2 for an overview, as well as

Table 2. Descriptive statistics for participants’ self-perceived changes in their daily food-consumption patterns during the COVID-19 pandemic and its restrictions in Germany.

Self-Reported Changes in Food-Consumption Behavioral Patterns	Sample	N	M	SD
I spend more time planning and preparing my meals and grocery shopping than usual	Cor1	3030	3.51	2.12
	Cor2	296	3.93	1.97
My cooking skills have improved.	Cor1	2957	3.44	2.03
	Cor2	292	3.92	2.06
I have tried many new dishes and/or new ingredients in my meals.	Cor1	3045	3.74	2.02
	Cor2	297	3.89	1.93
I have learned to use leftovers from my meals sensibly instead of throwing them away.	Cor1	2988	4.07	2.08
	Cor2	294	4.64	1.98
I ate out less often or got take-out from restaurants, cafeterias, canteens, or similar.	Cor1	3013	5.04	2.16
	Cor2	297	5.27	1.99

and

Table 3. Descriptive statistics for participants’ self-perceived changes in their food-consumption-related beliefs during the COVID-19 pandemic and its restrictions in Germany.

Self-Perceived Changes in Food-Consumption-Related Beliefs	Sample	N	M	SD
My cooking and eating habits have changed overall.	Cor1	3038	3.39	1.98
	Cor2	298	3.84	1.95
Overall, I have focused on my own diet more than before.	Cor1	3043	3.40	2.01
	Cor2	294	4.05	1.93
I view food as a more valuable resource than before.	Cor1	3015	3.99	2.05
	Cor2	297	4.68	1.77
I would be willing to pay higher prices for groceries than before.	Cor1	3013	3.65	1.94
	Cor2	297	3.84	1.86
It has become easier for me to stick with my self-determined diet.	Cor1	2958	3.72	1.93
	Cor2	293	4.25	1.79

for details).

With regard to the self-perceived COVID-19-related changes in the participants’ daily food-consumption patterns, the results implied comparatively strong perceptions of change but only when referring to the participants’ food consumption outside the home (M_COR1 = 5.04, SD_COR1 = 2.16; M_COR2 = 5.27, SD_COR2 = 2.00).

With regard to the perceived COVID-19-related changes in the participants’ food-consumption-related beliefs, the results from both surveys indicated the largest changes in the perception that food represents a valuable resource (M_COR1 = 3.99, SD_COR1 = 2.05; M_COR2 = 4.68, SD_COR2 = 1.77) as well as in the participants’ self-perceived ability to stick with self-determined diets in daily life (M_COR1 = 3.72, SD_COR1 = 1.93; M_COR2 = 4.25; SD_COR2 = 1.79; see Figure 2 for an overview and Table 3 for details).

3.2. COVID-19-Related Changes in People’s Daily Food-Consumption Patterns (RQ2)

The participants in the COR₁ survey reported significantly lower meat consumption (t₍₃₀₆₀₎ = −5.822, p < 0.001); significantly higher consumption of organic food (t₍₂₈₅₉₎ = 6.846, p < 0.001; see

Table 4. Participants’ engagement in diverse climate-friendly food-consumption behaviors during the COVID-19 pandemic and its restrictions compared with the pre-COVID-19 period.

Sample	Type of Climate-Friendly Food Consumption	N	MCOVID-19 (SD)	MPRE (SD)	t	df	p
Cor1	Meat consumption	3061	3.09 (1.10)	3.14 (1.09)	−5.822	3060	0.001 ***
	Consumption of organic food	2860	3.26 (1.37)	3.20 (1.36)	6.846	2859	0.001 ***
Cor2	Meat consumption	297	2.54 (0.86)	2.63 (0.87)	−3.395	296	0.01 **
	Consumption of organic food	297	3.34 (1.64)	3.34 (1.69)	−0.036	294	0.97
	Household food waste	297	1.98 (0.79)	2.12 (0.82)	−4.686	299	0.001 ***
	Consumption of regionally produced food	297	4.69 (1.26)	4.56 (1.28)	2.613	293	0.01 **
	Consumption of in-season food	297	5.03 (1.29)	4.74 (1.26)	6.000	291	0.001 ***
	Consumption of food with less plastic packaging	297	4.57 (1.47)	4.42 (1.52)	2.913	283	0.01 **
	Consumption of ready-made meals	297	2.11 (1.28)	2.20 (1.32)	−1.916	284	0.06

Notes. N = sample size (listwise case exclusion) ** p < 0.01. *** p < 0.001.

for details); and significantly lower levels of household food waste during the period in which the COVID-19 restrictions were in place in comparison with these behaviors reported for the pre-COVID-19 period (z = −3.448, p < 0.01).

In a manner mostly consistent with these results, the participants of the COR₂ survey also reported significantly lower meat consumption (t₍₂₉₆₎ = −3.395, p < 0.01); significantly lower household food waste (t₍₂₉₉₎ = −4.686, p < 0.001); and (almost) significantly lower consumption of ready-made meals (t₍₂₈₄₎ = −1.916, p < 0.06). Furthermore, the COR₂ participants reported significantly higher consumption of regionally produced food (t₍₂₉₃₎ = 2.613, p < 0.01), significantly higher consumption of in-season food (t₍₂₉₁₎ = 6.000, p < 0.001), as well as significantly higher consumption of food with less plastic packaging (t₍₂₈₃₎ = 2.913, p < 0.01). Only with regard to the consumption of organic food did the COR₂ survey not provide empirical evidence of a significant change in consumption levels when the COVID-19 restrictions were in place (t₍₂₉₄₎ = −0.036, p = 0.97; see again Table 4 for details).

Taken together, the results of both surveys nearly consistently implied diverse changes in people’s daily food-consumption patterns toward more climate-friendly food consumption during the period in which the COVID-19 restrictions were in place in Germany.

3.3. Durability of COVID-19-Related Behavioral Changes with Regard to the Post-COVID-19 Period (RQ3)

The participants of the COR₁ survey reported significantly lower intended meat consumption for an imagined post-COVID-19 period compared with the pre-COVID-19 period (t₍₃₀₂₈₎ = 21.591, p < 0.001); significantly higher consumption of organic food (t₍₂₈₂₄₎ = −24.325, p < 0.001; see

Table 5. Participants’ (intended) engagement in diverse climate-friendly food-consumption behaviors in an imagined post-COVID-19 period compared with the pre-COVID-19 period.

Sample	Type of Climate-Friendly Food Consumption	N	MPOST (SD)	MPRE (SD)	t	df	p
COR1	Meat consumption	3029	2.91 (1.06)	3.14 (1.09)	21.591	3028	0.001 ***
	Consumption of organic food	2825	3.55 (1.43)	3.22 (1.35)	−24.325	2824	0.001 ***
COR2	Meat consumption	297	2.59 (0.95)	2.63 (0.87)	1.207	294	0.23
	Consumption of organic food	297	3.70 (1.78)	3.34 (1.69)	−7.323	292	0.001 ***
	Household food waste	297	1.87 (0.62)	2.12 (0.82)	8.657	299	0.001 ***
	Consumption of regionally produced food	297	4.97 (1.33)	4.56 (1.28)	−7.637	293	0.001 ***
	Consumption of in-season food	297	5.03 (1.31)	4.74 (1.26)	−6.838	289	0.001 ***
	Consumption of food with less plastic packaging	297	4.83 (1.58)	4.43 (1.53)	−7.887	280	0.001 ***
	Consumption of ready-made meals	297	2.05 (1.25)	2.20 (1.33)	4.319	279	0.001 ***

Notes. N = sample size (listwise case exclusion) *** p < 0.001.

for details); and significantly lower intended household food waste for the next 12 months compared with the pre-COVID-19 period (z = −25.605, p < 0.001).

The COR₂ participants reported significantly lower household food waste (t₍₂₉₉₎ = 8.657, p < 0.001), as well as significantly lower consumption of ready-made meals (t₍₂₇₉₎ = 4.319, p < 0.001). Additionally, the COR₂ participants reported significantly higher consumption of organic food (t₍₂₉₂₎ = −7.323, p < 0.001) and significantly higher consumption of regionally produced food (t₍₂₉₃₎ = −7.637, p < 0.001), as well as significantly higher consumption of in-season food (t₍₂₈₉₎ = −6.838, p < 0.001. Only with regard to meat consumption did the COR₂ survey not provide empirical evidence of a significant change between intended meat consumption in the post-COVID-19 period compared with the pre-COVID-19 period (t₍₂₉₄₎ = 1.207, p = 0.23; see again Table 5 for details).

Nonetheless, when the surveys were combined, the results mostly implied a high probability that consumers would sustain long-term COVID-19-related changes toward more climate-friendly food consumption.

3.4. The Role of People’s Personal Climate-Protection Norms for COVID-19-Related Changes toward More Climate-Friendly Food Consumption and with Regard to the Post-COVID-19 Period

3.4.1. Data Analyses for the Identification of Linear Effects

In order to examine the possible linear effects of the participants’ personal climate-protection norms on changes toward more climate-friendly food consumption while the COVID-19 restrictions were in place, as well as with regard to (intended) long-term changes in the post-COVID-19 period compared with the pre-COVID-19 period, we computed multiple regression analyses. To do so, we initially calculated new variables representing such behavioral changes, which were later used as dependent variables in the regression analyses.

Data Analyses with the COR₁ Data

Using the COR₁ data, we calculated a dependent variable representing reduced meat consumption (with positive values representing reduced meat consumption) as well as increased consumption of organic food (with negative values representing increased consumption) during the period when the COVID-19 restrictions were in place compared with the pre-COVID-19 period. Furthermore, we calculated dependent variables representing intentions to reduce meat consumption (with positive values representing intentions to reduce meat consumption) as well as intentions to increase consumption of organic food (with negative values representing intentions to increase consumption) during the post-COVID-19 period compared with the pre-COVID-19 period.

When conducting linear regression analyses with these newly developed dependent variables, we controlled for the effects of potentially relevant sociodemographic features (i.e., age, gender, education, and income). Although the analyses we conducted revealed significant effects of the participants’ personal climate-protection norms on all the examined dependent variables, the identified beta values of these significant effects suggested that they were comparatively irrelevant (e.g., [42]), ultimately explaining only small amounts of variance in the dependent variables (see

Table 6. Results of multiple regression analyses of effects of participants’ sociodemographic features (control variables) and their personal climate-protection norms (independent variable) on changes toward more climate-friendly food consumption during the time period when the COVID-19 restrictions were in place, as well as during the post-COVID-19 period compared with the pre-COVID-19 period (COR₁ data only).

Dependent Variables		N	Explained Variance	Independent Variables	ß	p
Changes toward climate-friendly food consumption during the COVID-19 restrictions compared with the pre-COVID-19 period	Reduced meat consumption	3009	0.03%	Age	−0.01	0.56
				Gender	−0.01	0.77
				Education	0.03	0.14
				Income	−0.04	0.05 *
				Personal climate-protection norms	0.05	0.01 **
	Increased consumption of organic food	2826	0.02%	Age	0.01	0.66
				Gender	0.01	0.53
				Education	−0.04	0.08
				Income	0.04	0.08
				Personal climate-protection norms	−0.04	0.04 *
Changes toward more climate-friendly food consumption during the post-COVID-19 period compared with the pre-COVID-19 period	Intention to reduce meat consumption	2980	0.2%	Age	−0.09	0.001 ***
				Gender	−0.05	0.01 **
				Education	0.01	0.65
				Income	0.01	0.48
				Personal climate-protection norms	0.09	0.001 ***
	Intention to increase consumption of organic food	2791	0.1%	Age	0.10	0.001 ***
				Gender	0.03	0.18
				Education	0.01	0.74
				Income	0.02	0.25
				Personal climate-protection norms	−0.05	0.05 *

Notes. N = sample size (listwise case exclusion); ß = standardized beta values. * p < 0.05. ** p < 0.01. *** p < 0.001.

for details).

Data Analyses with the COR² Data

Apart from the larger numbers of dependent variables that were examined, we used the same data analytic procedures in the COR₂ sample as we used in the COR₁ data. Thus, initially, we calculated dependent variables that represented the participants’ behavioral change toward more climate-friendly food consumption during the COVID-19 restrictions, as well as with regard to long-term changes in the post-COVID-19 period compared with the pre-COVID-19 period. When conducting multiple regression analyses with these dependent variables, we did not find any significant effect of participants’ personal climate-protection norms on any dependent variable in the COR₂ data (see

Table 7. Results of multiple regression analyses of effects of participants’ sociodemographic features (control variables) and their personal climate-protection norms (independent variable) on changes toward more climate-friendly food consumption during the time period when the COVID-19 restrictions were in place, as well as during the post-COVID-19 period compared with the pre-COVID-19 period (COR₂ data only).

Dependent Variables		N	Explained Variance	Independent Variables	ß	p
Changes towards climate-friendly food consumption during the time period when the COVID-19 restrictions were in place compared with pre-COVID-19 period	Reduced meat consumption	269	−0.2%	Age	−0.00	0.25
				Gender	−0.02	0.70
				Education	0.01	0.42
				Income	0.00	0.89
				Personal climate-protection norms	0.02	0.20
	Reduced household food waste	272	3.9%	Age	−0.00	0.28
				Gender	0.17	0.01 **
				Education	0.01	0.60
				Income	0.07	0.02 *
				Personal climate-protection norms	−0.006	0.75
	Reduced consumption of ready-made meals	258	3.8%	Age	−0.01	0.01 **
				Gender	0.21	0.02 *
				Education	−0.00	0.98
				Income	−0.04	0.38
				Personal climate-protection norms	−0.01	0.67
	Increased consumption of organic food	269	−1.2%	Age	0.00	0.78
				Gender	−0.02	0.83
				Education	−0.03	0.34
				Income	0.01	0.82
				Personal climate-protection norms	−0.02	0.49
	Increased consumption of regionally produced food	267	0.5%	Age	−0.00	0.51
				Gender	−0.03	0.74
				Education	−0.04	0.32
				Income	0.04	0.44
				Personal climate-protection norms	−0.60	0.05
	Increased consumption of in-season food	266	0.01	Age	−0.08	0.21
				Gender	−0.05	0.44
				Education	0.04	0.56
				Income	−0.10	0.14
				Personal climate-protection norms	−0.13	0.04 *
	Increased consumption of food with less packaging	259	−1.7%	Age	0.00	0.96
				Gender	−0.05	0.63
				Education	−0.01	0.87
				Income	0.00	0.95
				Personal climate-protection norms	0.02	0.52
Changes toward more climate-friendly food consumption during the post-COVID-19 period compared with the pre-COVID-19 period	Intention to reduce meat consumption	268	−0.7%	Age	−0.00	0.37
				Gender	−0.08	0.21
				Education	0.01	0.59
				Income	−0.01	0.82
				Personal climate-protection norms	0.02	0.41
	Intention to reduce household food waste	272	10.8%	Age	−0.33	0.001 ***
				Gender	0.12	0.04 *
				Education	0.02	0.30
				Income	0.01	0.71
				Personal climate-protection norms	−0.02	0.25
	Intention to reduce consumption of ready-made meals	254	5.0%	Age	−0.24	0.001 ***
				Gender	0.05	0.45
				Education	0.03	0.22
				Income	0.01	0.73
				Personal climate-protection norms	0.01	0.60
	Intention to increase consumption of organic food	267	1.7%	Age	0.13	0.05 *
				Gender	−0.19	0.06
				Education	−0.03	0.51
				Income	0.03	0.63
				Personal climate-protection norms	−0.02	0.52
	Intention to increase consumption of regionally produced food	268	1.0%	Age	−0.00	0.83
				Gender	−0.27	0.02 *
				Education	−0.04	0.37
				Income	0.01	0.93
				Personal climate-protection norms	−0.02	0.53
	Intention to increase consumption of in-season food	264	7.1%	Age	0.12	0.06
				Gender	−0.19	0.01 **
				Education	−0.11	0.08
				Income	−0.01	0.91
				Personal climate-protection norms	−0.11	0.06
	Intention to increase consumption of food with less packaging	255	0.1%	Age	0.00	0.80
				Gender	−0.11	0.32
				Education	−0.02	0.59
				Income	0.09	0.12
				Personal climate-protection norms	−0.03	0.32

Notes. N = sample size (listwise case exclusion); ß = standardized beta values. * p < 0.05. ** p < 0.01. *** p < 0.001.

for details on the results of the multiple regression analyses we conducted with the COR₂ data).

Taken together, the analyses in either sample did not provide (strong) empirical evidence of relevant linear effects of the participants’ personal climate-protection norms on changes toward more climate-friendly food consumption during the COVID-19 restrictions or with regard to long-term changes in the post-COVID-19 period.

3.4.2. Data Analyses with Regard to Possible Nonlinear Effects

Effects of Personal Norms on COVID-19-Related Changes toward More Climate-Friendly Food Consumption

When comparing self-reported climate-friendly food-consumption measures during the period when the COVID-19 restrictions were in place compared with the pre-COVID-19 period between the participants characterized by high versus low personal climate-protection norms (i.e., high-norm vs. low-norm group), we found empirical evidence of the moderating effects of the participants’ personal norms for COVID-19-related changes.

With regard to the COR₁ data, these further analyses revealed a significant main effect of the participants’ personal climate-protection norms on COVID-19-related changes toward more climate-friendly food consumption with regard to meat and organic food consumption. Furthermore, the analyses provided empirical evidence for a (marginally) significant interaction effect between the time period (COVID-19 restrictions vs. the pre-COVID-19 period) and the participants’ personal norms, ultimately implying the moderating effects of personal norms on these changes. Thus, the high-norm group reported significantly larger reductions in their meat consumption during the COVID-19 pandemic and its restrictions than the low-norm group did (F = 10.460, p < 0.01; see

Table 8. High-norm versus low-norm participants’ engagement in diverse climate-friendly food-consumption behaviors during the COVID-19 pandemic and its restrictions compared with the pre-COVID-19 period.

Sample	Type of Climate-Friendly Food Consumption	Group	N	M (SD)PRE	M (SD)COVID-19	Time		Personal Norms		Interaction
						F	p	F	p	F	p
COR1	Meat consumption	Low	1425	3.32 (1.08)	3.30 (1.12)	2.892	0.09	89.445	0.001 ***	10.460	0.01 **
		High	1584	2.97 (1.07)	2.90 (1.06)
	Consumption of organic food	Low	1291	2.71 (1.31)	2.76 (1.32)	2.824	0.09	355.786	0.001 ***	3.486	0.07
		High	1535	3.61 (1.35)	3.69 (1.25)
COR2	Meat consumption	Low	158	2.63 (0.86)	2.62 (0.89)	0.964	0.33	0.068	0.79	7.903	0.01 **
		High	151	2.64 (0.85)	2.50 (0.86)
	Consumption of organic food	Low	158	2.80 (1.57)	2.79 (1.51)	0.102	0.75	30.834	0.001 ***	0.202	0.65
		High	151	3.79 (1.66)	3.83 (1.56)
	Consumption of regionally produced food	Low	156	4.22 (1.33)	4.28 (1.34)	0.061	0.81	24.054	0.001 ***	0.340	0.56
		High	151	4.83 (1.21)	5.00 (1.11)
	Consumption of in-season food	Low	158	4.39 (1.32)	4.60 (1.39)	1.605	0.21	26.859	0.001 ***	0.725	0.40
		High	149	5.03 (1.20)	5.33 (1.17)
	Consumption of ready-made meals	Low	153	2.35 (1.47)	2.22 (1.42)	2.333	0.13	1.325	0.25	0.727	0.39
		High	145	2.15 (1.32)	2.06 (1.28)
	Consumption of food with less packaging	Low	154	3.93 (1.52)	4.15 (1.53)	0.483	0.49	39.680	0.001 ***	3.360	0.07
		High	145	4.88 (1.36)	4.94 (1.33)
	Household food waste	Low	160	2.14 (0.89)	2.00 (0.82)	3.881	0.05 *	1.507	0.22	0.506	0.48
		High	152	2.05 (0.71)	1.93 (0.74)

Notes. N = sample size (listwise case exclusion); participants’ sociodemographic features were used as covariates within the analyses. * p < 0.05. ** p < 0.01. *** p < 0.001.

for details). Furthermore, the high-norm group also reported marginally significant greater increases in organic food consumption during the COVID-19 pandemic and its restrictions than the low-norm group did (F = 3.486, p < 0.07; see Table 8 again for details). With regard to household food waste, our data analyses indicated that both groups showed significantly smaller amounts of household food waste during the period in which the COVID-19 restrictions were in place (see

Table 9. High-norm versus low-norm participants’ household food waste during the COVID-19 pandemic and its restrictions compared with the pre-COVID-19 period (COR₁ data only).

Group	N	Difference between Household Food Waste Frequencies during the COVID-19 Restrictions—Frequencies during the Pre-COVID-19 Period		Z	p
		Number of Positive Differences	Number of Negative Differences
Low	1296	31	351	−16.321	0.001 ***
High	1476	32	469	−19.479	0.001 ***

Notes. N = sample size (listwise case exclusion). *** p < 0.001.

for details)—as would be expected on the basis of the results already presented in Section 3.2. However, in this context, it should be mentioned that the high-norm participants reported significantly lower household food waste levels for the pre-COVID-19 period than the low-norm participants did (U = −4.211, p < 0.001; Mdn_low = 3; Mdn_high = 2). Thus, the high-norm participants’ capacity for COVID-19-related changes toward more climate-friendly food consumption seemed to be more restricted compared with the low-norm group’s capacity for change.

With regard to the COR₂ data and in line with some of our previous findings (see Section 3.2), the additional analyses revealed some significant main effects of the time period (COVID-19 restrictions vs. the pre-COVID-19 period) as well as of the participants’ personal climate-protection norms on most of the captured changes toward more climate-friendly food consumption during the period in which the COVID-19 restrictions were in place compared with the pre-COVID-19 period (see again Table 8 for an overview). Furthermore, the data analyses also revealed a significant interaction effect between the time period and personal norms on COVID-19-related changes in meat consumption (F = 7.903, p < 0.01). In line with the COR₁ results, the high-norm participants in the COR₂ sample reported significantly larger reductions in meat consumption during the period in which the COVID-19 restrictions were in place than the low-norm participants did. Furthermore, the analyses also revealed another (but only marginally) significant interaction effect in the participants’ consumption of food with less packaging (F = 3.360, p < 0.07) with the high-norm participants reporting marginally significant higher consumption during the period in which the COVID-19 restrictions were in place than the low-norm participants did.

Taken together, the data analyses in both datasets provided some initial empirical evidence of the (not linear) moderating effects of consumers’ personal norms on COVID-19-related changes toward more climate-friendly food consumption—especially with regard to such changes in meat consumption. Thus, research hypothesis H1 was partially supported by our data.

Effects of Personal Norms with Regard to COVID-19-Related Changes in the Post-COVID-19 Period

When comparing the participants’ intended engagement in diverse climate-friendly food-consumption behaviors in the post-COVID-19 period compared with the pre-COVID-19 period between the personal norm groups, we also found some empirical evidence of the moderating effects of the participants’ personal climate-protection norms.

With regard to the COR₁ data—apart from the main effects of the time period and personal norms (see

Table 10. High-norm versus low-norm participants’ engagement in diverse climate-friendly food-consumption behaviors in the pre-COVID-19 period compared with the post-COVID-19 period.

Sample	Type of Climate-Friendly Food Consumption	Group	N	M (SD)PRE	M (SD) POST	Time		Personal Norms		Interaction
						F	p	F	p	F	p
COR1	Meat consumption	Low	1410	3.32 (1.08)	3.15 (1.09)	48.316	0.001 ***	112.515	0.001 ***	29.476	0.001 ***
		High	1570	2.98 (1.07)	2.69 (0.98)
	Consumption of organic food	Low	1268	2.73 (1.31)	3.03 (1.41)	66.023	0.001 ***	365.775	0.001 ***	8.773	0.01 **
		High	1523	3.62 (1.24)	4.00 (1.28)
COR2	Meat consumption	Low	158	2.63 (0.86)	2.65 (0.95)	1.468	0.23	0.275	0.60	1.660	0.20
		High	150	2.65 (0.86)	2.58 (0.98)
	Consumption of organic food	Low	157	2.80 (1.58)	3.10 (1.70)	2.325	0.13	30.653	0.001 ***	1.057	0.31
		High	150	3.80 (1.66)	4.24 (1.68)
	Consumption of regionally produced food	Low	156	4.22 (1.32)	4.53 (1.43)	0.478	0.49	24.762	0.001 ***	1.194	0.28
		High	151	4.83 (1.21)	5.281 (1.25)
	Consumption of in-season food	Low	157	4.39 (1.32)	4.59 (1.34)	0.333	0.56	27.185	0.001 ***	2.886	0.09
		High	148	5.03 (1.21)	5.42 (1.23)
	Consumption of ready-made meals	Low	153	2.34 (1.47)	2.22 (1.39)	3.414	0.07	2.164	0.14	0.439	0.51
		High	140	2.18 (1.34)	1.98 (1.23)
	Consumption of food with less packaging	Low	152	3.95 (1.55)	4.28 (1.61)	3.163	0.08	2.702	0.10	2.702	0.10
		High	143	4.92 (1.36)	5.44 (1.27)
	Household food waste	Low	160	2.14 (0.89)	1.88 (0.70)	6.712	0.01 **	1.288	0.26	1.830	0.18
		High	152	2.05 (0.71)	1.83 (0.52)

Notes. N = sample size (listwise case exclusion); participants’ sociodemographic features were used as covariates within the analyses. ** p < 0.01. *** p < 0.001.

for details)—the results also revealed significant interaction effects on the consumption of meat and of organic food. Thus, the high-norm group reported significantly stronger intentions to reduce their meat consumption (F = 29.476, p < 0.001), as well as significantly greater increases in their organic food consumption (F = 8.773, p < 0.01) in the post-COVID-19 period than the low-norm group did. Additionally, further data analyses on possible group differences referring to (intended) reductions in household food waste levels in the post-COVID-19 period (compared with the pre-COVID-19 period) only showed such significant intentions to reduce their waste by the high-norm group participants (z = −3.465, p < 0.01; see

Table 11. High-norm versus low-norm participants’ household food waste in the pre-COVID-19 period compared with the post-COVID-19 period (COR₁ data only).

Group	N	Difference between Household Food Waste Frequencies during the Post-COVID-19 Period—Frequencies during the Pre-COVID-19 Period		Z	p
		Number of Positive Differences	Number of Negative Differences
Low-norm	1380	83	102	−1.323	0.19
High-norm	1544	90	144	−3.465	0.01 **

Notes. N = sample size (listwise case exclusion). ** p < 0.01.

for details).

With regard to the COR₂ data—apart from some expectable main effects of time period and personal norms (see again Table 10 for details)—the results provided some marginally significant interaction effects of both factors on the captured climate-friendly food-consumption behaviors: Thus, the high-norm group reported marginally significant greater intentions to increase their consumption of in-season food (F = 2.886, p < 0.09), as well as to increase their consumption of food with less packaging (F = 2.702, p = 0.10) in the post-COVID-19 period than the low-norm group did.

Taken together, the data analyses in both datasets provided some initial empirical evidence of the (not linear) moderating effects of consumers’ personal norms on long-term COVID-19-related changes toward more climate-friendly food consumption with regard to the post-COVID-19 period. Thus, research hypothesis H2 was also partially supported by our data.

4. Discussion

Although the COVID-19 pandemic represents highly relevant consequences for global health and economic issues, COVID-19-related changes in people’s daily lives could also have desirable consequences with regard to global sustainability issues. On the basis of previous research that provided the initial empirical evidence that COVID-19 has offered a window of opportunity for promoting sustainable (behavioral) changes in people’s daily lives, the overall aim of the present study was to build on, as well as to extend, these initial findings with a specific focus on COVID-19-related changes in people’s minds and people’s behaviors with regard to climate-friendly food consumption in Germany. In this context, we wanted to explore the pandemic and its restrictions to serve as a window of opportunity for peoples’ long-lasting changes towards more climate-friendly food-consumption patterns.

4.1. Evaluation of Results

4.1.1. Consumers’ Self-Perceived COVID-19-Related Changes in Their Daily Food-Consumption and Food-Consumption-Related Beliefs

With regard to the present study’s first research objective, we explored consumers’ self-perceived COVID-19-related changes in their daily food-consumption patterns as well as in their food-consumption-related beliefs during the period in which the COVID-19 restrictions were in place in Germany. Thus, in line with some previous empirical results (see, e.g., [43]), we did not find very strong self-perceived changes in the participants’ daily food-consumption behavioral patterns or in their food-consumption-related beliefs during the pandemic. As expected with regard to political restrictions during the COVID-19 pandemic in Germany, the participants reported the largest changes with respect to their out-of-home food consumption during the period in which the COVID-19 restrictions were in place. These results are in line with results from studies conducted in other countries, such as England [22]. With regard to consumers’ self-perceived COVID-19-related changes in their food-consumption-related beliefs, we found the largest changes in the perception that food represents a valuable resource, as well as in the participants’ self-perceived ability to make better food choices in their daily life, indicating increased involvement in individual food-consumption patterns and cooking as well as changed food priorities during the pandemic. These results are in line with the findings provided by previous studies in other countries (see, e.g., [44,45]).

Taken together, these exploratory results imply that during the time period in which the COVID-19 restrictions were in place in Germany, consumers were better at dealing with grocery shopping and especially with the preparation of their own meals according to their individual needs and beliefs than they were in the pre-COVID-19 period. Especially with regard to consumers’ reported higher ability to stick with self-determined diets in daily life, we can assume that during the period in which the COVID-19 restrictions were in place in Germany, consumers’ individual food-consumption-related beliefs had a larger effect on their daily food-consumption behaviors. Against this background, an increase in the motivation to choose a healthy diet as well as to choose a climate-friendly diet may have been more probable.

4.1.2. COVID-19-Related Changes in People’s Food-Consumption Behavioral Patterns with Regard to Long-Term Changes in the Post-COVID-19 Period

In order to explicitly examine such assumptions about COVID-19-related changes toward more climate-friendly food consumption in Germany, we compared retrospectively self-reported engagement in diverse climate-friendly food-consumption behaviors between the time period in which the COVID-19 restrictions were in place and the pre-COVID-19 period. In line with empirical results provided for other countries, our data indicated such COVID-19-related changes in consumers’ climate-friendly food consumption. The results that were consistently found in both surveys—and that were already implied by previous research—showed that consumers significantly reduced the amount of meat they consumed (e.g., [15,17]) as well as their household food waste during the period in which the COVID-19 restrictions were in place (e.g., [21,46]). Furthermore, we also found COVID-19-related increases in people’s consumption of regionally produced food, in-season food, and food with less plastic packaging. In contrast to other studies that found changes in the consumption of organic food (e.g., [23]), our results did not imply any clear conclusion.

In addition to our investigation of the COVID-19-related changes in consumers’ climate-friendly food consumption in general, we also examined the durability of such changes with regard to long-term changes in these behaviors in an imagined post-COVID-19 period. So, when examining the participants’ intended behavioral engagement in diverse climate-friendly food-consumption behaviors, our results generally indicated such long-term effects. Referring to almost all of the types of climate-friendly food-consumption behaviors we examined, the participants reported higher intentions to engage in certain behaviors in a post-COVID-19 period than they had in the pre-COVID-19 period.

4.1.3. Moderating Effects of Personal Climate-Protection Norms on COVID-19-Related Changes toward More Climate-Friendly Food Consumption

On the basis of previous (environmental) psychological research on the effects of people’s personal climate-protection norms on the promotion of their climate-friendly food-consumption behaviors (see Section 1.3 for details), which was in line with our results indicating that consumers’ individual food-consumption-related beliefs had a stronger effect on their daily food-consumption behaviors in general during the time period in which the COVID-19 restrictions were in place in Germany (see Section 4.1.1), we examined the possible moderating effects of consumers’ personal climate-protection norms on COVID-19-related changes toward more climate-friendly food consumption and the durability of the change with regard to the post-COVID-19 period.

Although we did not find any strong empirical evidence of a linear moderating effect, there was some empirical evidence of relevant interaction effects between COVID-19-related behavioral changes toward more climate-friendly food consumption and consumers’ personal norms. Thus, most of the empirical evidence of such an interaction effect was found for reductions in consumers’ meat consumption during the time period in which the COVID-19 restrictions were in place, as well as for their intended meat consumption in the post-COVID-19 period based on COR₁ data. So, although we referred to the consumption of other types of climate-friendly foods that were captured in our surveys, our empirical findings remained ambiguous. However, we still provided initial empirical evidence that consumers’ personal climate-protection norms—in addition to promoting the main/direct effect on consumers’ engagement in climate-friendly food-consumption behaviors—can also interact significantly with temporal changes in external/situational factors [35,36], as such changes resulted from the COVID-19 pandemic and its restrictions in Germany. Against this background, our findings implied such changes to be effective in breaking up peoples’ stable food-consumption patterns and, thus, the pandemic serves effectively as a window of opportunity, which should also be considered by governance/political decision makers in order to further promote climate-friendly food consumption in Germany.

4.2. Practical and/or Policy Implications of Our Findings

In line with other scholars (e.g., [47]), our results stress the impact that established work and everyday life conditions have on food choices. People normally cover many distances a day when they depend on out-of-home consumption. Consequently, due to COVID-19 restrictions, people reported the largest changes with respect to this out-of-home consumption.

Although this finding seems trivial, it is highly relevant for policy makers, particularly when connecting it to the result indicating that people seem to be willing to consume in a more climate-friendly way if they have the chance to prepare their own food at home. To that end, educational campaigns informing about climate-friendly food consumption at home could therefore be fruitful options for the fostering of sustainable diets.

However, the question is whether climate-friendly nutrition should be the responsibility of the individual rather than a societal and political issue. Currently, out-of-home choices seem to make climate-friendly food consumption harder for people than at home (see also [47]). There are many ways to change this for policy makers.

For example, folk kitchens or canteens located in every city district could allow everyone to consume a warm, healthy, climate-friendly, and affordable meal a day. This would not only foster more sustainable food environments but could also provide a great relief for families that struggle to provide healthy food for their children, particularly under the already tensioned life and working conditions of the COVID-19 pandemic. Moreover, these canteens could be ideal places to also learn about climate-friendly food choices at home.

4.3. Limitations and Implications for Future Research

Altogether, the present study represents an initial step in research on COVID-19 as a window of opportunity to help move people toward more climate-friendly food consumption in Germany. Nonetheless, there are, of course, diverse limitations that must be considered when interpreting the current empirical findings. At the same time, these limitations point out relevant directions for future research, alongside our study’s conclusions.

4.3.1. Limitations for Conclusions about Causality

Even though we tried to use a more robust research design to analyze behavioral changes using both retro- and prospective data, final conclusions on causality cannot be made on the basis of cross-sectional data. Ideally, an additional survey should be administered to examine the potential long-term effects of the pandemic and its restrictions on consumers’ climate-friendly food consumption as well as on their food-consumption-related beliefs.

4.3.2. Limitations Referring to the Measures Used in the Present Study

There are a few limitations with respect to the measures used in our surveys that should be considered: (a) We did not measure actual behavior but relied on (retro- and prospective) self-reports, ultimately restricting the reliability of the captured behavior due to possible response biases. On the one hand, reliability could be restricted due to memory biases (i.e., unintended inaccuracies in participants’ self-reported behaviors caused by retrieval-problems, see, e.g., [48] for more information). On the other hand, the data quality could have been also negatively affected by some intended response biases, especially with regard to the participants’ intentions to answer our questions in a socially desirable way, i.e., in order to present themselves as acting in a climate-friendly food-consuming way (see, e.g., [49] for an overview on social desirability response bias). Thus, these limitations, typically related to self-reported measures, make clear that future research should further examine the present research questions by using more robust empirical measures, such as dietary recall data or household scanner data.

(b) Furthermore, for the sake of comparability with the data from other studies (these comparisons were interpreted in a different publication, see [50]), we had to measure some types of climate-friendly food consumption in the COR₁ survey using an ordinal scale (i.e., household food waste levels). This may have decreased the statistical power of the analyses that we computed to investigate our research questions and hypotheses. Furthermore, due to survey length issues in the COR₁ survey, we were able to capture only three different types of climate-friendly food consumption (i.e., meat consumption, consumption of organic food, and household food waste). This is why comparisons between the results from the two surveys (COR₁ and COR₂)—to determine the replicability of the findings and, thus, the stability and generalizability of our results—are restricted to only these kinds of climate-friendly food-consumption behaviors. Furthermore, it should be mentioned, that there are some types of climate-friendly food consumption, which were not considered in our study due to survey length issues (for example, people’s consumption of dairy products). Thus, there is also a need for future studies examining COVID-19-related behavioral changes, referring to further types of climate-friendly food consumption in order to finally result in a complete picture of all pandemic-related behavioral effects for climate-friendly food consumption.

(c) Furthermore, future studies should examine the effects of additional cognitive variables that could (also) be relevant predictors and/ or moderators of individual behavioral changes toward more climate-friendly food consumption that could not be assessed with the present surveys due to survey length. In this context, the need for integrating additional predictors and moderating variables for explaining COVID-19-related behavioral changes is clearly pointed out by our data when considering the small amounts of variance that could by explained in the regression analyses we described in Section 3.4. Having in mind that previous environmental psychological research provided empirical evidence for diverse predictors of climate-friendly behavioral changes (in addition to peoples’ sociodemographic features as well as to their personal norms for climate-protection; see Section 1.3 for details), it seems not quite surprising that the amount of explained variances in our measures of COVID-19-related behavioral changes remained small. Thus, future studies should integrate further predictors and moderating variables for peoples’ COVID-19-related behavioral changes toward more climate-friendly food consumption, such as other climate-protection-related variables (e.g., people’s social norms for climate-friendly food consumption, etc.; see, e.g., [26]), as well as variables which are generally determining for people’s food choices (e.g., taste of food, price and economic issues; see e.g., [51] for an overview).

4.3.3. Limitations Regarding the Generalizability of the Results

We examined our research questions and hypotheses by collecting data from two similar but independent samples that differed to some extent in their sociodemographic features in order to provide a partial replication and, thus, more stable/generalizable findings. Nonetheless, the generalizability of our findings remains restricted. For example, with regard to the sociodemographic features of the COR₂ sample, it has to be mentioned that our participants seemed to have a higher-education level compared to the German population (see Table 1 for details). This issue could mention itself in different ways when interpreting our results. Based on the fact that higher education is usually positively correlated with more sustainable attitudes and behaviors (see, e.g., [52] for an example), it seems assumable that the identified COVID-19-related behavior changes towards more climate-friendly food consumption in the COR₂ sample could have been—at least partially—promoted by the participants’ education. Thus, it cannot be completely excluded, that we might have not found comparable empirical evidence for COVID-19-related behavioral changes toward more climate-friendly food consumption in a lower-educated sample of German consumers. On the other hand, the higher-educated COR₂ sample could have been characterized by—compared to the German population—already existing higher levels of climate-friendly food-consumption patterns in their daily food consumption in pre-COVID-19 times. Consequently, the overall potential for COVID-19-related behavioral changes towards more climate-friendly food consumption could have been strongly restricted in this sample, making it more difficult to identify such (small) changes with our behavioral measures. Thus, it seems also possible that we could have found stronger empirical evidence for COVID-19-related behavioral changes towards more climate-friendly food consumption in a lower-educated sample of German consumers. Against this background, it seems necessary that future studies examining COVID-19-related effects on people’s climate-friendly food consumption should also consider such specific sociodemographic features of the examined samples.

Apart from the issues mentioned earlier with respect to the restricted generalizability when referring to the specific sociodemographic features of the examined samples, as well as with respect to the restricted comparability of behavioral measurement between the two surveys (see Section 4.2 for details), it should also be mentioned that both surveys were conducted only in samples of German citizens. Furthermore, both surveys studied the impact of the COVID-19 pandemic and its restrictions only in the specific time frame of April to June/July 2020. Therefore, our findings are restricted to the German population as well as to this specific time period. Thus, we do not yet know whether our findings can be generalized to other populations or to other time periods with COVID-19 restrictions (e.g., in spring or winter 2021/2022). Therefore, future research should consider this limitation by studying the potential of the COVID-19 pandemic for promoting climate-friendly food consumption in other populations and with regard to other time periods with COVID-19 restrictions.

5. Conclusions

Despite the great negative societal consequences of COVID-19 and its associated political restrictions, at least the situation has also resulted in some (behavioral) changes toward sustainability and has opened windows of opportunity for long-term behavioral change. In this context, the present study provided (further) empirical evidence that people have embraced more climate-friendly food-consumption behaviors during the COVID-19 pandemic and the time period in which the restrictions were in place in Germany and indicated that long-term changes may persist in the post-COVID-19 period as well. Furthermore, our findings point to the relevance of people’s personal climate-protection norms for behavioral changes toward more climate-friendly food consumption, both during and potentially beyond the pandemic. Thus, taken together, our study implies that the COVID-19 pandemic may offer a potential window of opportunity for the promotion of climate-friendly food consumption in Germany and beyond. On this basis, our findings imply the importance of such strong changes in external/situational factors, which should be considered by political decision makers in order to further promote long-lasting changes in peoples’ behaviors and, thus, to promote global climate-protection.