Assessing Environmental and Economic Sustainability of Fresh Unpacked, Fresh Packed, and Frozen Carrots in Austria: A Case Study with a Life Cycle Assessment (LCA) Approach

Abstract

(1) Background: LCA is an established method for the systematic analysis of the environmental impact of products throughout their life cycle. (2) Methods: The LCA on fresh (un)packed and frozen carrots, with system boundaries from the cradle to supermarket gate and the functional unit of 1 kg of carrots, is applied using openLCA 1.11, Agribalyse v 3.1 and is calculated with EF 3.0. A sensitivity analysis of transport and carrot loss was made. To consider economic sustainability, a cost calculation for transportation and cooled storage is conducted. (3) Results: The impact category of climate change for fresh carrots results in 0.186 kg CO₂ eq for unpacked carrots, 0.200 kg CO₂ eq for LDPE-packed carrots, and 0.195 kg CO₂ eq for PLA-packed carrots. Transportation accounts for the largest impact, with up to 50% resulting from the transportation distance and the use of cooled lorries, followed by post-harvest handling (15–21%) and cultivation (21–22%). PLA-packed carrots save 2.4% of CO₂ and 6.0% of fossil energy compared to LDPE-packed carrots. Regional carrots with short transportation distances require only 57% of CO₂. Frozen carrots have a threefold higher result of 0.614 kg CO₂ eq, resulting mostly from the high amounts of energy required for production and frozen storage. Post-harvest handling contributes to 43% of CO₂, followed by supermarket storage (27%) and transport (22%). The transportation costs for frozen carrots are 24% higher than for fresh carrots, and their storage costs are 3.8 times higher at 0.181 EUR/kg. (4) Conclusion: Frozen carrots are more expensive and have a greater environmental impact. Nevertheless, they are relevant for the preservation of agricultural products and year-round availability.

1. Introduction

Life Cycle Assessment (LCA) is a structured, comprehensive, and internationally standardized method for assessing the environmental impact of a product, service, or technology [1,2]. Nowadays, it is the most established and widely used method to assess environmental impact [3]. The global standards of the International Standard Organization for environmental LCA management (ISO 14040 and ISO 14044) provide the essential framework for the methodology LCA (available online: www.iso.org) [4,5] provide the essential framework for the methodology LCA, with the iterative steps being Goal and Scope Definition, Life Cycle Inventory, and Life Cycle Impact Assessment [6,7,8].

The calculation of the environmental impact of companies and products is increasing due to the mandatory sustainability reporting in the Corporate Sustainability Reporting Directive (CSRD) with the European Sustainability Reporting Standards (ESRS). The CSRD (Directive (EU) 2022/2014) is a law that requires companies to publish sustainability information on various topics related to environmental and social issues and to improve non-financial reporting. The goal of the reporting is to contribute to the European Green Deal and the Paris Agreement. It aims to increase the demand for sustainability information on undertakings and to address the vulnerability of workers and business value chains identified in the COVID-19 pandemic [9,10]. The ESRS E1–E5 are standards about the environment, and all five standards recommend the LCA as a methodology, while some of them recommend EF as a calculation method [11].

For this case study, carrots were chosen since plant-based diets have become very popular and have been identified as a dietary strategy associated with protection against chronic disease [12]. Also, carrots were the second most consumed vegetable and the third most cultivated vegetable in Austria in 2022 [13]. The self-supply of carrots in Austria is 94%, and the main cultivation region is Marchfeld in Lower Austria [14].

An overview of seven available previous LCA studies on fresh carrots is shown in

Table 1. Overview of existing LCA studies in literature on carrots.

Reference	Country	System Boundary	Functional Unit	GWP in kg CO2 eq
[15]	Brazil	Cradle to farm	1 kg of harvested carrots	0.077–0.119 *
[16]	Poland	Cradle to farm	1 kg of produced carrots	0.035
[17]	France	Cradle to farm	1 kg of marketable carrots	0.066
[18]	Italy	Cradle to retail gate	1 kg of LLDP packed carrots	0.135
[19]	Sweden	Cradle to retailer	1 kg of carrots at retailer in Helsingborg	0.09
[20]	Finland	Cradle to retailer	1 kg of LDPE-packed carrots at supermarket	0.142–0.280 **
[21]	Sweden	Cradle to retailer	1 kg of carrots at farm	0.086

* recommended scenario—base scenario. ** cultivated in Finland—cultivated in Italy.

. All studies report the global warming potential (GWP) results for 1 kg of carrots. However, the individual studies are from different countries and use different system boundaries. System boundaries from cradle to farm include the whole carrot cultivation process but no transportation to post-harvest handling. Their GWP ranges from 0.035 kg CO₂ eq to 0.119 kg CO₂ eq. System boundaries from cradle to retail gate include all processes (cultivation, transport, post-harvest handling, and transport) to the supermarket but not storage at supermarket, resulting in a GWP range from 0.09 kg CO₂ eq to 0.135 kg CO₂ eq. System boundaries from cradle to supermarket are comparable to the system boundaries of this study. They have a GWP of 0.086 kg CO₂ eq. System boundaries from cradle to consumer gate incorporate all process steps until consumer but not the storage and consumption at consumer, and it has a GWP of 0.216 kg CO₂ eq. However, no studies on LCA for frozen carrots are available so far.

The aim of this case study is to assess the environmental and economic sustainability of fresh (un)packed and frozen carrots. The LCA on carrots is carried out in Austrian supermarkets. This study does not consider carrots in direct sales, weekly markets, or farm shops. For the targeted application of the LCA, a market analysis in the form of a store check is carried out. Then, carrots are assessed in the LCA in terms of their sustainability based on specific environmental impacts. The following research questions are answered: What is the environmental impact of fresh carrots, and to what extent does plastic packaging, conventional and bioplastic, contribute to this? What is the environmental impact of frozen carrots? Differences in environmental sustainability between fresh and frozen carrots and between conventional plastic and bioplastic are identified. Also, the process steps with the greatest environmental impact and saving opportunities for the environment are determined. A cost comparison between fresh and frozen carrots is made to consider economic sustainability in addition to environmental sustainability.

2. Materials and Methods

2.1. Life Cycle of Carrots

The cultivation begins with sowing in February and harvesting from the beginning of June until the end of November. Carrots are either sold, processed, or stored until the next harvest season in June of the following year [22]. Before selling, carrots are processed into different end products. Carrots are mostly processed into fresh carrots, frozen carrots, or carrot juice [23]. The processing scheme for vegetables is as follows: transportation and storage, then mechanical treatment (washing, sorting, chopping), then thermal treatment (blanching/steaming), then preservation (conserving, drying, freezing, pasteurizing, sterilizing), then packing [21]. Fresh vegetables are mechanically treated before packaging. Frozen carrots are mechanically and thermally treated before freezing for preservation and packaging.

To produce fresh carrots to sell at supermarkets, the raw product is transported to post-harvest handling after harvesting and storage in dark, refrigerated rooms at around 2 °C for a maximum storage duration of six months. The carrots are gradually removed from storage and mechanically processed according to consumer demand. After storage and just before distribution to supermarkets, they are sorted, machine-washed, dried, and packed [20]. After packaging, carrots are transported in a lorry at ambient temperature to distribution centers or directly to supermarkets.

For the production of frozen carrots, the raw material is transported to post-harvest handling after harvest and is processed immediately, usually within one to three days. The carrots are washed and graded, steam-peeled, cut into the desired shape, and blanched to kill any bacteria while preserving vitamins and color. Finally, the carrots are frozen at −35 °C and packaged. They are transported to the supermarket frozen via truck. Frozen carrots can be stored for several months to years [23]. The advantages of freezing carrots include greater convenience for the consumer, longer storage time without spoilage, more flexibility in food preparation, and high nutritional quality. Frozen vegetables can therefore increase vegetable consumption, avoid food waste among consumers, and contribute to a healthy and balanced diet. Furthermore, through freezing, excess capacity at the producer can be buffered [24,25]. In addition, carrots are cut during processing, so there is less food waste due to non-achievement of the quality grade [23].

2.2. Case Study on Austrian Carrots

Figure 1 shows the overall steps of the methodology for this case study on fresh unpacked, fresh packed, and frozen carrots. The methodology LCA for this case study is established and implemented using data from the store check carried out as part of the case study. Economic sustainability is considered in the course of a cost calculation for transport and refrigerated storage.

2.2.1. Store Check

In a market analysis, data on available fresh and frozen carrot products in Austrian and German supermarkets are collected by means of a store check. Information on country of origin, carrot categories, packaging material and portion size, storage duration, and price were gathered and are summarized in the following. The raw data of all 52 products assessed are included in Supplementary Materials.

• Country of origin: In Austrian supermarkets, 85% of the carrots are grown in Austria. In German supermarkets, 44% of carrots are grown in Germany.
• Carrot categories: Fresh packed carrots without green make up the biggest category, followed by frozen carrots and fresh unpacked carrots.
• Packaging material: A total of 75% of frozen carrots are packed in cardboard. Fresh carrots are mostly packed in plastic, especially in LDPE (n = 12) and bioplastic (n = 7) (if unspecified plastic is not considered). All carrots in bioplastic come from and are sold in Austria.
• Portion size: Frozen carrots are mainly sold in 300 g bags, while fresh carrots are sold in 1 kg bags.
• Storage duration: The mean storage duration until best before date for frozen carrots is 17 months. The average duration of fresh carrots until for sale is six days.
• Price: The option with the cheapest mean price is fresh packed carrots in LDPE at 1.52 EUR/kg, followed by carrots in bioplastic at 1.93 EUR/kg, and unpacked fresh carrots at 2.22 EUR/kg. Frozen carrots are the most expensive product, with a mean price of 7.01 EUR/kg.

2.2.2. Environmental Sustainability

Environmental sustainability is calculated using the Life Cycle Assessment methodology. The iterative process steps of Goal and Scope Definition, Life Cycle Inventory, Life Cycle Impact Assessment, and Sensitivity Analysis are described in the following.

2.2.3. Goal and Scope Definition

The goal of this study is to assess and compare fresh carrots in different plastic packaging as well as frozen carrots that are cultivated, produced, and sold in Austrian supermarkets.

The scope of the study includes the following four scenarios:

• Fresh unpacked carrots
• Fresh packed carrots in LDPE
• Fresh packed carrots in PLA
• Frozen carrots packed in cardboard

To ensure comparability, all scenarios are scaled to the functional unit of 1 kg of carrots at a supermarket.

The system boundaries are from cradle to supermarket gate, and the process with its inputs and outputs for each process step is summarized in Figure 2. All scenarios follow the same process. The scenarios differ in the processing steps post-harvest handling for fresh unpacked, fresh packed, and frozen carrots.

2.2.4. Life Cycle Inventory

The software openLCA 1.11 is chosen because it is open access, Agribalyse can be integrated, and cost calculation is not of primary interest. The methodology of the LCA is based on existing studies and processes available in Agribalyse [26,27].

The data for the input and output flows of the four scenarios are are collected following the decision to use the openLCA software and the Agribalyse database. The data collection is based on LCA studies of carrots in the literature, see Table 1 and the Agribalyse database. Only data from literature and the store check are used. The store check data is used for packaging material, packaging weight, transportation distance, and storage duration.

According to literature, the cultivation and harvesting of carrots that are processed into frozen products differ slightly from fresh carrots [23]. For simplicity and better comparability, it is assumed that the process steps until post-harvest handling are the same for all scenarios in the case study (

Table 2. Life Cycle Inventory for process steps of carrot cultivation and transportation from farm to processing.

Process Step	Description	Process Name in Agribalyse	Amount	Unit	Source
	Yield		77,500	kg/ha	[28]
Carrot cultivation [25,27,29]	INPUT
	Seeds	Carrot, seed, conventional, at farm gate/FR	1.94 × 10−5	kg	[29]
	Fertilizer	Average mineral fertilizer N, at regional storehouse/FR	2.19 × 10−3	kg	[28,29]
		Average mineral fertilizer P2O5, at regional storehouse/FR	6.45 × 10−4	kg	[28,29]
		Average mineral fertilizer K2O, at regional storehouse/FR	3.23 × 10−3	kg	[28,29]
		Dolomite, at mine (WFLDB 3.5)/RER	3.87 × 10−2	kg	[20,30,31]
	Pesticides	Herbicides: Pendimethalin	2.05 × 10−5	kg	[18,32,33]
		Fungicides: Azoxyrobin	6.45 × 10−6	kg	[18,32,33]
		Fungicides: Difenoconazol	1.29 × 10−6	kg	[18,32,34,35]
		Fungicides: Copper oxychloride	4.28 × 10−5	kg	[18,32,35,36]
		Insecticide: Lambda-Cyhalothrin	9.68 × 10−8	kg	[18,37]
		Insecticide: Chlorantraniliprole	4.52 × 10−7	kg	[17,18,38]
	Water for irrigation	Water, river, AT	19.40	l	[23]
	Fuels for field work	Diesel {Europe without Switzerland}	3.76 × 10−3	kg	[18,39]
	Land occupation	Occupation, annual crop, irrigated	1.29 × 10−5	ha	[28]
	OUTPUT
	Carrot at cultivation		0.94	kg
	Food loss	Green waste and straw, shredded	0.06	kg	[40]
	N2O	Dinitrogen monoxide	5.29 × 10−5	kg	[41]
	CO2	Carbon dioxide, fossil	4.65 × 10−3	kg	[42]
Transportation 1	INPUT
	Carrot at cultivation		1.00	kg
	Lorry 7.5–16 metric ton	Transport, freight, lorry 7.5–16 metric ton, EURO5 {RER}	23.6	kg∗km	Store check [43]
	OUTPUT
	Carrot at transport		1.00	kg

).

The post-harvest handling, transportation, and supermarket stages are presented for fresh carrots (unpacked, LDPE-packed, and PLA-packed) (Figure 2) and include the energy consumption of cooled storage for four months before processing (Table 3) [44]. The processes differ only in the packaging step, which consumes about 1% of the energy and includes the packaging materials LDPE or PLA. It is assumed that packaging processes for PLA and LDPE require the same amount of energy. The process for PLA production is the only input modeled in openLCA. The result for the impact category climate change is 2.4 kg CO₂ eq/kg for PLA. Considering the carbon uptake by plant growth, it is 0.59 kg CO₂ eq/kg for PLA [45]. Compared to LDPE with 2.87 kg CO₂ eq/kg, PLA is more environmentally sustainable. The carrot loss during sorting and washing in post-harvest handling of fresh carrots is 20% on average during storage over a time period of 7 months, as carrots may rot, or their quality may deteriorate during the time of storage [19,46].

In supermarkets, the food loss for fresh carrots is 4% [47]. In general, food loss is low. The food loss of carrots at a supermarket varies depending on the supermarket branch [48]. Therefore, a sensitivity analysis for carrot loss at supermarket is done.

Table 3. Life Cycle Inventory for fresh carrots (carrot unpacked, carrot packed in LDPE, carrot packed in PLA) from post-harvest handling until storage at supermarket.

Process Step	Description	Process Name in Agribalyse	Carrot Unpacked	Carrot LDPE-Packed	Carrot PLA-Packed	Unit	Source
Post-harvest handling	INPUT
	Carrot at transport		1.20	1.20	1.20	kg	[46]
	Electricity	Electricity, medium voltage {AT}	0.292	0.295	0.295	MJ	[18,44]
	Water	Tap water {Europe without Switzerland}	3.00	3.00	3.00	l	[49]
	LDPE foil	Packaging film, LDPE {RER}	-	4.60	-	g	Own data
	PLA Granule	Process according to Kara et al. [49]	-	-	4.60	g	Own data
	OUTPUT
	Carrot LDPE post-harvest handling		1.00	1.00	1.00	kg
Transportation 2	INPUT
	Carrot LDPE post-harvest handling		1.00	1.00	1.00	kg
	Transport lorry 16–32 metric ton	Transport, freight, lorry 16–32 metric ton, euro6 {RER}	506	506	506	kg∗km	Store check; [50]
	OUTPUT
	Carrot LDPE at transportation		1.00	1.00	1.00	kg
Storage at supermarket	INPUT
	Carrot LDPE at transportation		1.04	1.04	1.04	kg	[47]
	Electricity	Electricity, medium voltage {AT}	0.280	0.280	0.28	MJ	[51]
	OUTPUT
	Carrot fresh LDPE		1.00	1.00	1.00	kg

Table 3. Life Cycle Inventory for fresh carrots (carrot unpacked, carrot packed in LDPE, carrot packed in PLA) from post-harvest handling until storage at supermarket.

Process Step	Description	Process Name in Agribalyse	Carrot Unpacked	Carrot LDPE-Packed	Carrot PLA-Packed	Unit	Source
Post-harvest handling	INPUT
	Carrot at transport		1.20	1.20	1.20	kg	[46]
	Electricity	Electricity, medium voltage {AT}	0.292	0.295	0.295	MJ	[18,44]
	Water	Tap water {Europe without Switzerland}	3.00	3.00	3.00	l	[49]
	LDPE foil	Packaging film, LDPE {RER}	-	4.60	-	g	Own data
	PLA Granule	Process according to Kara et al. [49]	-	-	4.60	g	Own data
	OUTPUT
	Carrot LDPE post-harvest handling		1.00	1.00	1.00	kg
Transportation 2	INPUT
	Carrot LDPE post-harvest handling		1.00	1.00	1.00	kg
	Transport lorry 16–32 metric ton	Transport, freight, lorry 16–32 metric ton, euro6 {RER}	506	506	506	kg∗km	Store check; [50]
	OUTPUT
	Carrot LDPE at transportation		1.00	1.00	1.00	kg
Storage at supermarket	INPUT
	Carrot LDPE at transportation		1.04	1.04	1.04	kg	[47]
	Electricity	Electricity, medium voltage {AT}	0.280	0.280	0.28	MJ	[51]
	OUTPUT
	Carrot fresh LDPE		1.00	1.00	1.00	kg

The post-harvest processing of frozen carrots results in a loss of 60% of the raw material. It requires 7.4 times more energy and 2.8 times more water than the process for freshly packed carrots. The packaging material cardboard, weighing 22.04 g, is 4.8 times heavier than the plastic packaging of fresh carrots.

The only difference in transportation from post-harvest handling to supermarkets is the temperature during transportation. Fresh carrots are transported at ambient temperatures, frozen carrots at below −18 °C.

Frozen carrots have no food loss during storage at the supermarket [48]. For frozen carrots, the energy for refrigerated storage in the supermarket is calculated using the average shelf life of 17 months from the store check and the energy for refrigeration of frozen vegetables [52]. This means that storage until the end of the best before date is already included in the supermarket storage.

Only a small amount of primary data is collected for this study (

Table 4. Life Cycle Inventory for carrot frozen cardboard packed from post-harvest handling until storage at retailer.

Process Step	Description	Process Name in Agribalyse	Amount	Unit	Source
Post-harvest handling	INPUT
	Carrot at transport		0.48	kg	[46]
	Electricity for Processing	Electricity, medium voltage {AT}	0.262	MJ	[53]
	Electricity for Heating	Electricity, medium voltage {AT}	0.390	MJ	[53]
	Water	Tap water {Europe without Switzerland}	2.55	l	[49]
	Corrugated board box	Corrugated board box {RER} | production	22.04	g	Own data
	OUTPUT
	Carrot frozen post-harvest		0.30	kg
	Biowaste	Biowaste, shredded	0.183		[54]
Transportation 2	INPUT
	Carrot frozen post-harvest		1.00	kg
	cooled transport, lorry 16–32 metric ton	Chilled transport, lorry 16–32 t, EURO5	506	kg∗km	Store check; [50]
	OUTPUT
	Carrot frozen at transportation		1.00	kg
Storage at supermarket	INPUT
	Carrot frozen at transportation		1.04	kg	[47]
	Electricity	Electricity, medium voltage {AT}	1.862	MJ	[52]
	OUTPUT
	Carrot frozen		1.00	kg

). Therefore, the data used for the Life Cycle Inventory is mainly obtained from literature, databases, and store checks. This can lead to inaccuracies in the results. Some of the data, which are taken from databases, are already somewhat older. For example, the data in ProBas, which is used for the post-harvest handling and storage processes, are based on the years 1990 to 1994, calculated for the year 2020 [44,51,52,53]. Furthermore, Austrian data for carrots is not available for all process steps. Data from studies from Italy, Finland, Sweden, Poland, and Germany are used with the French database Agribalyse [16,18,20,21]. The geographical differences may also lead to inaccuracies.

2.2.5. Economic Sustainability

Life Cycle Assessment covers the sustainability pillar of the environment. This is one of the three pillars of sustainability: social, economic, and environmental [55]. To get a broader understanding of the sustainability of carrot products, the pillar economy is considered. For this purpose, the energy costs are calculated using the result of LCA impact category resource use fossil in MJ. These are converted to kWh and then calculated with the mean energy price for the food industry for the region Groß-Enzersdorf in the year 2023 of 0.20 EUR/kWh [56]. These are compared with the mean price from the store check for each of the four carrot scenarios.

Furthermore, the transport and storage costs for fresh and frozen carrots from post-harvest handling to supermarket are calculated. The transportation costs include the diesel consumption of the lorry and the refrigeration unit. The diesel costs for the lorry are calculated from the kilometers driven, the diesel consumption per 100 km, and the cost per liter of diesel. The refrigeration unit is calculated based on the running time, diesel consumption per hour, and the cost of diesel [57,58]. The average price of one liter of diesel is 1.52 EUR [59].

The storage costs are calculated using the energy consumption for refrigerated and frozen storage and the costs for 1 kWh. The cooling and freezing unit is from the Tecto series from Viessmann [60]. A maximal room volume in m³ is given for defined conditions. The amount of carrot packages that fit in the volume of 1 m³ is calculated using the measured size of the carrot packages. The number of carrot packages per m³ and the energy amount per m³ is calculated by the energy amount (kW) per kg of carrot. The energy amount in kWh is multiplied by the maximal storage duration in days, using data from literature and store checks, and the assumed running time for hours of the cooling unit per day. This is calculated with the price of 0.20 EUR/kWh to achieve the total price for cooling/freezing per kg carrot [56].

3. Results and Discussion

This section presents and discusses the environmental and economic sustainability results of fresh and frozen carrot products based on the LCA results from cradle to supermarket gate and cost comparison and calculation.

3.1. Environmental Sustainability

Environmental sustainability is calculated with the LCA for 1 kg of carrots at a supermarket with the software openLCA and the calculation method EF 3.0, see Section 2.

3.1.1. Life Cycle Impact Assessment

The results are calculated with a LCA calculation method in the Life Cycle Impact Assessment and are shown in impact categories.

In the context of this study, EF 3.0 is used since it concerns carrots in Austria and, accordingly, the European framework is sufficient. In addition, on 15 December 2021, the European Commission adopted Recommendation (EU) 2021/2279 on the use of EF calculation methods to measure and disclose the environmental performance of products along their life cycle [61]. Also, ESRS E1 to E5 of the CSRD recommend calculation and data collection using LCA and EF [11].

The ESRS refers to the impact categories climate change (ESRS E-1), pollution (ESRS E-2), water and marine resources (ESRS E-3), biodiversity and ecosystem (ESRS E-4), and resource use and circular economy (ESRS E-5). Focusing on the reporting of ESRS E-2 and E-5, the results of material flow analysis of inventory analysis are of interest [11]. This case study focuses on the ESRS E-1 reporting on climate change and energy consumption. Therefore, the impact categories of climate change and resource use fossil are analyzed, and the results are shown in

Table 5. LCIA results for the impact categories climate change and resource use fossil for the four carrot scenarios.

	Carrot Fresh Unpacked	Carrot Fresh LDPE-Packed	Carrots Fresh PLA-Packed	Carrots Frozen, Cardboard
Climate change in kg CO2 eq	0.19	0.20	0.20	0.61
Resource use, fossil in kWh	0.73	0.84	0.79	2.40

. The category climate change, furthermore can be compared to the GWP results of existing LCA studies on carrots [11].

• Climate change

Fresh unpacked carrots have the lowest value in the impact category of climate change with 0.186 kg CO₂ eq, followed by fresh carrots packed in PLA (0.195 kg CO₂ eq), and fresh carrots packed in LDPE (0.200 kg CO₂ eq (Table 5). All fresh carrots are in the same range for the GWP. Frozen carrots have about three times higher climate change impact (0.614 kg CO₂ eq) compared to fresh carrots. The examined impact categories land use, water use, eutrophication freshwater and marine, and resource use fossils show a similar distribution in their results, which can be seen in Supplementary Materials.

All process steps except post-harvest handling of fresh carrots require the same amount of CO₂ (Figure 3). The contribution factors for fresh carrots (unpacked, LDPE-packed, and PLA-packed) are cultivation with 0.041 kg CO₂ eq (21–22%), first transportation with 0.006 kg CO₂ eq (3–4%), second transportation with 0.086 kg CO₂ eq (43–46%), and storage at the supermarket for four months with 0.025 kg CO₂ eq (12–13%). Total transport has the largest influence on fresh carrots with 46–50%. The post-harvest handling process contributes to 0.028–0.042 kg CO₂ eq (15–21%), depending on the packaging. They are indicators, that the packaging for LDPE contributes higher to the total process than the process of PLA contributes, which is based on the carbon uptake by the plants used to make PLA [49]. The total life cycle savings potential of PLA-packed carrots is 2.6% compared to LDPE-packed carrots.

Frozen carrots packed in cardboard require a higher amount of CO₂ in all process steps compared to fresh carrots. Post-harvest handling has the largest impact, accounting for 42% (0.262 kg CO₂ eq) of the total process. This process alone has a higher GWP than the entire process for fresh carrots. The storage at a supermarket with 0.165 kg CO₂ eq or 27% of the total process has a 6.6 times higher impact on climate change than the storage of fresh carrots. This is due to the higher energy amount and the longer storage period of 17 months, which is the maximum storage period from the store check. Frozen transportation requires 0.127 kg CO₂ eq or 21% of the total process’ CO₂ and is one-third higher compared to ambient transportation for fresh carrots. This is due to the cooling aggregate for transportation. Farming (0.053 kg CO₂ eq) and first transportation (0.008 kg CO₂ eq) are 29% higher compared to fresh carrots. This is due to greater food loss during the processing stage for frozen carrots.

• Resource use fossil

The results of the impact category resource use fossil are calculated in MJ. Since the ESRS E1 reports on MWh, they are converted to kWh by the conversion factor of 1 MJ, resulting in 0.2778 kWh [62,63]. Figure 4 shows the consumption of fossil energy in the different process steps for all carrot scenarios.

The total fossil energy used for one kilogram of fresh carrots is 0.73–0.84 kWh. The processes for fresh carrots (unpacked, LDPE-packed, and PLA-packed) require the same amount of fossil energy in the process steps of farming (0.13 kWh), first transportation (0.03 kWh), second transportation (0.36 kWh), and at the supermarket (0.10 kWh). The differences in fossil energy use for the post-harvest handling of fresh carrots are noticeable. LDPE-packed fresh carrots consume twice as much fossil energy (0.22 kWh) as unpacked carrots (0.11 kWh). PLA-packed carrots consume 0.17 kWh. This is partly due to the higher energy input for packaging, but it is also due to the fact that LDPE is made using fossil fuel energy. The energy consumption for the post-harvest handling of carrots packed in PLA is 25% lower than that of carrots packed in LDPE. For fresh carrots packaged in LDPE, replacing the packaging material with PLA can save 6% of the total fossil energy consumption.

For frozen carrots, the total fossil energy use is three times higher than for fresh carrots at 2.4 kWh/kg, which is equivalent to lighting a 60-watt light bulb for 20.8 h [64]. The farming stage uses 0.17 kWh. Transportation uses 0.03 kWh, the post-harvest handling 1.03 kWh, second transportation uses 0.52 kWh, and the storage at the supermarket uses 0.65 kWh. The high consumption of the post-harvest handling of frozen carrots is striking. This is due to the high energy input required during processing. The greatest potential for savings is in post-harvest handling and storage at the supermarket.

The goal of saving fossil energy for frozen carrots can be achieved through optimized processing and cold storage. For fresh packaged carrots, PLA, a bioplastic, can save 6% of the total fossil energy compared to LDPE-packed carrots. In terms of plastic production alone, the production of PLA saves 29% of the fossil energy used in the production of fossil-based plastics [65]. PLA saves about 66% of the energy required to produce conventional plastic [66].

In this case study, with the calculation method EF 3.0, just Midpoint and no Endpoint categories were investigated [67]. Endpoint categories summarize Midpoint categories into three Areas of Protection and represent the following interests of society: (1) human health, (2) the natural environment, and (3) natural resources. They are easier to interpret. However, it is difficult to track and trace the results, so they are therefore simplified.

It can be concluded that food loss prevention has low CO2-saving potential compared to transport. The greatest saving potential lies in reducing transport distances. Therefore, efforts should be made to keep the transport distances of carrots as short as possible. Long transportation distances have an important impact on GHG emissions. Carrots produced in Italy and sold in Sweden/Finland consume two to three times the total CO₂ [20,21]. The results of the store check in Section 2.2.1 show that 85% of the carrots sold in Austria come from Austrian agriculture. The literature reports self-sufficiency for carrots of 94% in Austria [14]. This shows that regionality at the country level is already important for carrots in Austria. Regionality within a province would be even better. Carrots sold at MPreis in Tyrol are grown and processed in Hall in Tyrol, which indicates short transport distances and saves 43% of the GHG emissions [68]. In Germany, in contrast, the self-supply according to the literature is 78%, where carrot loss of up to 10% can occur [48,69]. The results of the store check show a lower self-sufficiency rate of 44%. The remaining 56% come from European agriculture.

3.1.2. Classification of Results to Literature, Database, and Store Check

The results of the climate change impact category for fresh and frozen carrots can be classified using results from literature, database processes and a product from the store check, see

Table 6. Classification of results for fresh and frozen carrots in the existing literature, database results, and store check product on the process steps of cultivation, post-harvest handling, and supermarket.

Source	Carrot Product	GWP in kg CO2 eq
		Carrot at Cultivation		Carrot at Processing	Carrot at Supermarket
Fresh carrot
Case study	Carrot fresh unpacked	0.033	0.073	0.186
	Carrot fresh LDPE-packed	0.033	0.086	0.200
	Carrot fresh PLA-packed	0.033	0.081	0.195
Literature	[16]	0.035
	[15]	0.077/0.119 *
	[17]	0.066
	[18]		0.135
	[19]			0.090/0.275 **
	[20]			0.142/0.280 ***
	[21]	0.048	0.061	0.086
Database	Agribalyse raw carrot	0.057		0.240
Frozen carrot
Case study	Carrot frozen	0.033	0.323	0.614
Database	Agribalyse frozen LDPE	0.033	0.355	0.455
Store check	followfood GmbH (Friedrichshafen/Germany) frozen organic carrots			0.517

* base scenario/recommended scenario, ** carrots produced and sold in Sweden/carrots produced in Italy and sold in Sweden, *** carrots produced and sold in Finland/carrots produced in Italy and sold in Finland.

. Each source defines the system boundaries individually. This allows the processes to be modeled up to different process stages. The GWP results of the case study in kg CO₂ eq are applied and compared to the process stages of carrots in cultivation, carrots at processing, and carrots at the supermarket. The raw data for the four carrot scenarios of the LCA are listed at each process level in Supplementary Materials. First, the outcomes for fresh carrots across various processing stages are compared, and then the results for frozen carrots are compared.

• Comparison of results for fresh carrots

The results for climate change for carrot cultivation in the case study of 0.033 kg CO₂ eq is in the same range as the GWP reported by Kowalczyk (2020) [16] with 0.035 kg CO₂ eq. The results of Lopes et al. (2018) [15] are two to three times higher than the process in the case study. This can be explained by the 30 times higher diesel and P₂O₅ fertilizer input, the 11 times higher carrot seed input, and the 1.5 times higher N and K₂O fertilizer input. Grasselly et al. (2017) [17] indicate results of 0.066 kg CO₂ eq for 1 kg marketable carrots. The reasons for the double amount compared to the process in this study cannot be discussed, as no Life Cycle Inventory is available for the process. The GWP for conventional carrot agricultural production from Jareborg (2019) [21] is 0.048 kg CO₂ eq, which is 45% higher than the process from this case study. The system boundaries of Jareborg include the production and maintenance of the process machinery, leading to higher results.

The processes from cradle to carrots for processing include the steps of cultivation, transportation, and post-harvest handling. The results of this case study are 0.073 kg CO₂ eq–0.086 kg CO₂ eq. The GWP of Ilari et al. (2020) [18] is 0.049 kg CO₂ eq higher compared to the scenario of fresh LDPE in post-harvest processing. This is due to the longer transport distances to the processing plant, which are 150–1000 km depending on the cultivation area. In this case study, the transportation distance to process is 23.6 km. Jareborg (2019) [21] reports a 0.020 kg CO₂ eq lower GWP for conventional LDPE-packed fresh carrots. The reasons for the lower results are the 1.5% lower food loss at Jareborg and the exclusion of transportation from farm to post-harvest processing.

This LCA case study for fresh carrots to the supermarket includes the process steps of cultivation, transport, post-harvest handling, transport to the supermarket, and storage at the supermarket. These results are compared to studies by Karlsson (2012) [19], Raghu (2014) [20], and Jareborg (2019) [21], which do not include storage at the supermarket. All three studies report lower results compared to the results of this study. The reasons for this are the shorter transportation distance and the lack of refrigeration at the supermarket. The Agribalyse process includes storage at the supermarket for fresh unpacked carrots and has 0.054 kg CO₂ eq higher results for GWP compared to the process unpacked in the case study. The reasons for this are the longer transportation distance (600 km) and higher energy consumption at the supermarket (0.695 MJ). Overall, the range of literature and database results for GWP for fresh carrots at the supermarket is 0.086–0.280 kg CO₂ eq. The processes in this study are within the range.

• Comparison of results for frozen carrots

For frozen carrots, the range in the database and the store check results are 0.455–0.517 kg CO₂ eq. The process in this case study is outside this range. It is 0.159 kg CO₂ eq higher than the process from Agribalyse and 0.097 kg CO₂ eq higher than the results for frozen organic carrots from followfood GmbH (Friedrichshafen/Germany). No Life Cycle Inventory is available for the process from followfood GmbH (Friedrichshafen/Germany). Therefore, no further discussion can be had. Agribalyse has a lower result. This is explained by the lower amount of energy during processing (0.057 MJ) and storage at the supermarket (0.748 MJ) and less food loss (11%). There is no LCA study on LCA for frozen carrots available in the literature, which shows the novelty of this work. Thus, the result cannot be further classified.

In conclusion, each study defines a different system boundary, is conducted in a different country, and uses different software and LCA methods. Therefore, each LCA process is individual and can only be compared with other results to a limited extent.

The price comparison of the calculated energy price from resource use fossil and the mean price of the products from the store check are shown in

Table 7. Price comparison for 1 kg of carrots’ calculated energy price from EF 3.0 impact category resource use fossil and the mean store check price for the four carrot scenarios.

	Store Check Mean Price in EUR/kg	Calculated Price from EF 3.0 in EUR/kg
Fresh unpacked carrots	2.22	0.16
Fresh LDPE-packed carrots	1.52	0.18
Fresh PLA-packed carrots	1.93	0.17
Frozen cardboard-packed carrots	7.01	0.50

. The mean prices from store checks range from 1.52 EUR to 7.01 EUR. The calculated energy prices range from 0.16 EUR to 0.50 EUR. This represents only the costs for energy consumption and not for any raw material.

The cheapest and most common product in the store check is fresh carrots packed in LDPE. Their calculated energy price is the third-highest after fresh unpacked carrots (0.16 EUR/kg) and fresh PLA-packed carrots (0.17 EUR/kg) at 0.18 EUR/kg. The calculated price for carrots packed in LDPE is higher due to the higher energy consumption during packaging and the higher fossil energy consumption as LDPE is fossil-based. PLA, on the other hand, is plant-based and saves fossil resources. The store check price for carrots packed in PLA (1.93 EUR/kg) is higher than that of LDPE-packed carrots. This can be explained by the 0.55–0.75 EUR/kg higher price for PLA compared to LDPE [70]. Fresh unpacked carrots have the lowest calculated price but the third-highest price from the store check at 2.22 EUR/kg. The reason for the higher price is the shorter shelf life. According to Johnsson et al. (2008) [71], the shelf life of carrots can be extended up to 17 days under good storage conditions, i.e., cold storage in micro-perforated packaging.

Frozen carrots are the most expensive product in the store check and have the highest calculated price. Possible reasons for the 4.6 times higher price compared to fresh LDPE-packed carrots are the long storage of up to years and the more complex processing, which requires more machinery and labor hours [23,72].

3.1.3. Cost Calculation for Transportation and Cooled Storage

The observation that the calculated energy price for frozen carrots is higher than that of fresh carrots is confirmed by the calculated transportation and storage costs for 1 kg of carrots (

Table 8. Calculated costs for (un)cooled transportation and cooled and frozen storage per kg carrot.

	Transportation		Storage
	Tractor-trailer	Tractor-trailer + freezing unit (−30 to −18 °C)	Cooled storage	Frozen storage
Total price in EUR/kg of carrots	0.010	0.012	0.040	0.181

). The detailed calculation for transportation and storage duration is described in Supplementary Materials.

The costs for transportation for tractor-trailers from post-harvest handling to the supermarket are 0.010 EUR/kg of carrots if only the cost of diesel for a truck with a total load of 20,000 kg is taken into account. The costs for the driver and the truck are not considered. The freezing unit is added separately. In total, the frozen transport of 1 kg of carrots costs 0.012 EUR. The transport costs for frozen carrots are 20% higher than those for fresh carrots. The difference in the cost of transporting 1 kg of fresh carrots compared to frozen carrots is small. If the material and labor costs for transport are added, the percentage difference of currently 20% becomes even smaller.

The storage cost of frozen carrots is 3.8 times higher than that of fresh carrots. The cost of cooling fresh carrots is 0.040 EUR/kg for a storage period of 180 d. The storage cost for frozen carrots is 0.181 EUR/kg for a storage period of 630 d. Different storage times are chosen to reflect the life cycle of fresh and frozen carrots. The main reason for the higher price is the longer storage period of frozen carrots compared to fresh carrots. The power required to cool fresh carrots (0.00018 kW/kg) is about 80% of the energy required to chill frozen carrots (0.00023 kW/kg).

It can be concluded that the costs and environmental impacts of frozen carrots are higher than those of fresh carrots. A contributing factor is the long shelf life. This is the advantage of frozen vegetables, in addition to the convenience factor and flexibility in preparation [25]. Shorter storage times are therefore not feasible. No costs were calculated for the processing of carrots, which highly contributes to environmental impact. Furthermore, the data for the Life Cycle Impact Assessment was taken from the ProBas database, which is not transparent [53]. A closer look at processing is relevant for recommending potential savings for frozen vegetables. This could be an area for future research.

4. Conclusions

The LCA methodology is complex. Decisions about software, databases, and LCA calculation methods have to be made before and during the modeling process. These decisions influence the final result, so time should be allocated to the preparation of the LCA. The four steps of the LCA are clearly defined, and the development of the process is structured according to them. However, it should be noted that the LCA is individual for each process. Decisions about process boundaries, simplified process definitions, and data collection are made individually. It is expected that LCA will become more important due to mandatory sustainability reporting under the CSRD for companies starting in 2024. LCA is recommended as a calculation method by environmental standards. Therefore, it is necessary to make the method more accessible to companies and to keep it simple. One possibility is to provide generalized processes in databases that companies can adapt according to their process.

In this case study about fresh unpacked, fresh packed, and frozen Austrian carrots, the process boundaries are set from cradle to the end of the supermarket. The LCA normally considers the entire life cycle of a product, from cradle to grave, including consumer usage. Along the food supply chains, the energy supply and logistics play a fundamental role in the determination of economic and ecological sustainability values and are intensively investigated. In contrast, there are limitations within the literature about consumer behavior, like the distance from supermarket to consumer and the storage or processing of carrots in households. The process for the consumer stage would be a best guess and is not included. The Manchester Food Research Centre [73] reports that frozen food causes less waste than fresh food in households. Eberle and Fels [47] report that 34.6% of fresh vegetables purchased are lost at the consumer stage, while only 3.5% of frozen vegetables are lost.

The results for the three scenarios of fresh unpacked carrots, fresh carrots packed in LDPE (a fossil-based plastic), and fresh carrots packed in PLA (a bio-based plastic) show similar results and are within the range of the GWP in the category climate change reported on LCA for carrots in literature. Packaging has little effect on GHG emissions. However, the use of PLA, a bio-based alternative to LDPE, has the potential for environmental sustainability by saving fossil energy. The main contribution factor of fresh carrots to environmental impact is the transport process, which implies that the most significant factor in promoting environmental sustainability is to grow carrots locally, thus minimizing transport distances. The cost of transport is slightly higher for frozen carrots, but the cost of refrigeration is considerably higher for frozen carrots due to long storage periods. The convenience factor of the long storage duration is one of the main advantages of frozen carrots.

The case process is modeled on the software openLCA, and the data in the Life Cycle Inventory is collected from the literature, market data within the scope of a store check, and the Agribalyse database. For a universal process overview, the strategy was sufficient. For individualized processes, however, primary data collection is preferable, with a cradle to grave approach to generate valid results.

In terms of environmental and economic sustainability, it is better to store fresh carrots throughout the year instead of freezing them. Due to their good storage stability, carrots can easily be kept in processors’ warehouses from the end of November until the beginning of the next harvest season in early June. This means that fresh carrots can be offered to consumers all year round. Another possibility is the preservation of fresh carrots with other technologies, like drying or pasteurizing carrot juice, canned carrots, or ready-to-eat carrot salad, so that no energy for cooled storage is needed. An additional aspect that has to be included is that the freezing process successfully and resourcefully preserves the products. For this reason, the barrier demands on frozen food packaging are less complex. Fresh products require multi-layer packaging that deals with a wide range of functionalities, while a limited oxygen and water barrier is needed for frozen food packaging.

However, there are no existing LCA studies in the literature, which show the novelty of this research. There is available data on the LCA of frozen carrots in the Agribalyse database and one product on the market: frozen organic carrots from followfood GmbH (Friedrichshafen/Germany). Both show lower results than the LCA of frozen carrots in this study. The main factors contributing to the process in this study are post-harvest processing, frozen storage, and transport. Therefore, the potential savings lies in more efficient process steps and shorter transport distances. The reasons for freezing carrots are not economic or environmental sustainability, but convenience for the consumer, preservation and thus buffering of excess capacity at the producer, and year-round availability of high nutritional quality.

For further investigations, a comprehensive analysis of processing frozen carrots is of interest to identify both environmental and economic savings potential. It could also be interesting to calculate the environmental impact of other preserved carrot products, like canned carrots, carrot juice, dried carrots, or carrot salad. Primary data collection and a cradle-to-grave process could also be interesting to look at consumer-level influences such as storage, preparation, and food loss on frozen and fresh carrots. Also of interest for further research is the question whether the packaging of fresh carrots may reduce the environmental impact over the whole life cycle. It is assumed that by protection of the carrots through the packaging, the shelf life of packaged fresh carrots is extended, and therefore, food loss is reduced.