1. Introduction
Pulses are dry seeds of starchy leguminous crops cultivated worldwide, serving as a source of protein, dietary fiber, vitamins, and minerals [
1,
2]. The most produced pulses include common bean, pea, chickpea, cowpea, and lentil, and their global production is over 71 million tons (5-year average of 2016–2020) [
3]. In addition to their nutritive values, evidence has been accumulating that pulses provide protective effects against cardiometabolic diseases and certain types of cancer [
4,
5]. Due to their health-promoting effects, a weekly consumption of 1.5 cups of pulses is recommended by the Dietary Guidelines for Americans for a 2000-kcal diet [
6]. In addition, pulses are a key component of sustainable diets. Like other legumes, pulses demonstrate biological nitrogen fixation which reduces dependency on commercial fertilizers [
7,
8,
9]. About 2.9 million tons of common bean, pea, chickpea, and lentil are produced in the U.S. annually (5-year average of 2016–2020) [
3]. However, whole pulse consumption is low in the U.S., with about 20% of adults reporting consumption of dry, canned, or frozen pulses in the previous 24 h [
10]. Barriers to pulse utilization include limited time for meal preparation, gastrointestinal discomfort, and lack of knowledge on dry pulse cooking [
11,
12,
13,
14]. Pulse flours (milled pulses) offer solutions to some of the barriers, as they can be processed into a broader range of ready to eat or quick to prepare food products, such as baked goods, snacks, pasta, and extruded products [
15,
16]. The high levels of protein and dietary fiber (15–30% each) in pulses make their flours an ideal ingredient to increase nutritional quality of traditionally wheat-flour based products [
4,
15]. Wheat flour alternatives are gaining attention, especially pea and chickpea flours, due to increasing consumer interest in the nutritional and health benefits of pulse flours [
17,
18]. In fact, pulse flour, starch, or protein were listed 1666 times as ingredient(s) in food products launched in the U.S. in 2016–2020, and peas accounted for 65% of these [
19].
Numerous studies have been conducted to investigate the suitability of pulse flours for various food applications with various substitution ratios to wheat flour [
20,
21,
22]. Pulse flour utilization brings some challenges such as off- and ‘beany’ flavors and product texture. Functional properties of pulse flours are different from wheat flour due to the lack of gluten [
22,
23,
24]. Thakur et al. [
25] compared pulse and wheat flours with established milling quality specifications. They assert that pulse flour description and seed quality parameters for pulse milling need to be defined for industry consistency. A lack of studies on the effect of genotype, environment, storage, processing, and milling on those quality parameters, as well as flour components and their interactions, was noted [
25]. Performance can vary depending on pulse flour and application types, and flours can be characterized by many attributes, such as dehulling efficiency, physicochemical properties, thermal behavior, and nutrient composition [
21,
26,
27,
28]. End-product qualities, such as appearance, aroma, and flavor, are also important to consider for consumer acceptability.
The perspectives of end-users on pulse flours (i.e., the food industry) are scarce in the literature. One case study, conducted among European and multinational food manufacturers of pulse-based products, identified important factors for pulse-based product development [
29]. Those factors were grouped into three categories: technical aspects, market trends, and ingredient availability. Technical aspects included the functionality and behavior of pulse flours when processed. As expected, the difference between regular wheat flour and pulse flours was noted. While dependent upon time and country, this research found that market trends were strong drivers for company product development. Wary consumer attitudes towards new foods were deemed to be a challenge for pulse-based pasta in Europe, although they were more accepted in the U.S. Ingredient availability was a concern, especially to firms with large production capacities. Since this study was conducted almost exclusively with firms in Europe, a similar study with U.S. food manufacturers is needed to facilitate an improved understanding of the pulse flour-related challenges more specific to the U.S.-based firms. In addition, important pulse flour traits depend on application types. Therefore, optimum pulse flour traits need to be specified for each type of application.
Common bean (
Phaseolus vulgaris, L.) is the most produced pulse crop globally and in the U.S. [
3] Approximately one million tons of dry beans are harvested annually and consumed primarily in the form of canned beans in the U.S. [
30] However, beans can also be milled into flour and used for food products that are typically made from wheat flour. Bean flour has been tested for various food applications on a laboratory scale, such as quick bread [
31,
32], tortillas [
33] pasta [
34,
35,
36], cookies [
24], biscuits [
37], cakes, crackers, and meat analogues [
38], with promising results. Bean flour has been commercially produced and used, but its market presence remains rather small. Among the aforementioned 1666 counts of pulse use in food products, bean flour accounted for only 3% of them [
19]. Aroma, appearance, texture, and beany flavor, likely caused by lipid oxidation, may be a challenge [
38], not only for bean flour but also for other types of pulse flours [
25,
39]. This suggests that there is a need to improve beans for use as flour, but exactly which traits do not meet the expectations of users are not clear. Moreover, some pulses, including beans, contain high levels of lectins, which can be toxic to the human digestive system when consumed raw but be safe after proper cooking [
13]. Knowledge and attitudes about lectins among food manufacturers are an important consideration for improving beans for flour, but relevant information is limited.
Despite some of the possible challenges, their positive impact on sustainability and human health makes pulse flours a promising ingredient for food products. The number of products that utilize pulse flours is rising [
18,
40]. From breeders’ perspective, however, specific needs for pulse flours by the food industry is an important missing piece of information for developing pulse varieties for flour purposes. This survey study aimed to identify the needs for pulse flours and the barriers limiting the adoption of them by U.S. manufacturers making typically wheat flour-based food products, e.g., pastas, breads, and baked goods.
3. Results and Discussion
Through direct emails and the weblink, 130 responses were collected in total, which included 1 duplicate and 16 declinations. Twenty-nine responses were incomplete, 5 were from outside the U.S., and 4 by businesses irrelevant to wheat or pulse flours. Of the 75 valid responses, 6 were collected via the weblink and 2 via additional invitation emails. Respondents were categorized into four pulse flour user groups for survey question comparisons: 8 current users, 4 previous users, 9 considered users, and 54 non-users. The most common role of the respondents was management or owner (n = 29), followed by research and development (R&D, n = 18). Only 40% (30/75) of the respondents were in R&D or production/chef, who are most likely to be knowledgeable about the behavior of pulse flours when utilized in food products. However, 50% of the current users and 67% of considered users were in R&D, whereas 25% and 13% of the previous and the non-users were in R&D, respectively.
3.1. Pulse Flour and Product Types
Participants were asked to choose a specific pulse flour type and product type they would like to produce with the pulse flour they selected (
Table 2). Chickpea and pea flours were the most frequently selected as compared to bean, fava, and lentil flours. Sixty-nine percent of non-users did not know which pulse type was best for their needs. Thirteen percent of non-users indicated that they were not interested in using any pulse flours. Over half of ‘considered users’ selected chickpea, whereas 63% of current users and 50% of previous users selected pea flour.
Among all the respondents, yeast breads were the most selected products to use pulse flour for, followed by cookies and quick breads (
Table 3). Twenty percent of non-users indicated that they were uninterested in using pulse flours for any products. Though chickpea and pea were the most selected pulse type (
Table 2), the type of products using the pulse flours selected varied widely (
Table 4). However, yeast breads and cookies (selected nine times each) were relatively popular among those who did not know which type of pulse flour is best for their needs.
3.2. Pulse Flour Information
Regarding pulse flour specification or technical information, 75% of the current, 100% of the previous, 78% of the considered users, and 11% of the non-users had looked for technical information on pulse flour. Among those who had looked for information, 61% (14 out of 23) were able to find sufficient information. More CPC users had looked for information on pulse flours than non-users, and 89% of non-users never looked for technical information on pulse flours.
Participants who had looked for information about pulse flours were asked to select all sources of information they consulted. Multiple choices were allowed, and 22 out of the 23 selected at least one source of information. For-profit researchers and industry associations, such as the Institute of Food Technologists, were the most selected source of information (n = 15). Non-profit organizations, such as the American Pulse Association and academic textbooks and researchers, were the second most selected (n = 14). Open-access journals (n = 8) were more popular than subscribed and pay-per-view journals (n = 4). Those who selected “Other” commented that information was obtained from their suppliers (n = 3) and from the Internet (n = 1). From these results, academic and for-profit organizations and communication between researchers seemed to be effective channels likely to reach end-users who sought out information about pulse flours.
3.3. Impression on Bean Flour
To gain insights on how beans could be improved for flour purposes, participants were asked for their impressions of bean flour. Multiple answers were allowed. “Do not know about bean flour” was the most selected impression on bean flour, especially by non-users (57%). However, 25–33% of the CPC users also did not know about bean flour (
Table 5). Over 60% of the current and the considered users selected “Flavor is a challenge”. All user types selected “Market demand for bean flour is low”. Flavor and functionality were selected as a challenge 22 and 21 times, respectively, whereas gluten contamination and lectin concerns were only selected 6 times in total. Given the low familiarity with bean flour, it is possible that participants were unfamiliar with lectins in beans. A comment mentioned the expected low production volume of bean flour: “Volume limitations limit its commercial usage”. To our knowledge, information about the proportion of beans used commercially as flour in the U.S. is not readily accessible.
3.4. Pulse Flour and Product Types of CPC Users
The CPC users were asked the types of pulse flour and the product they are using/used. Yeast breads were the most selected (n = 6), followed by snack foods (n = 5) and plant-based meat alternatives (n = 4) (
Table 6). For the eight current users, the most selected reason for using pulse flours was driven by marketing and trends, followed by protein content and functional characteristics of the pulse flour (
Table 7). The reason for discontinuing pulse flour by the four previous users were all “Low market demand for the product made with the pulse flour”. No other choices regarding flour performance, supply, or allergen contamination were selected as the reason for discontinuation. These results suggest that market demand is an important determinant on whether or not to use pulse flour. In relation to that, low market demand ranked fourth for bean flour impression (
Table 5).
3.5. Satisfactory and Challenging Characteristics of Product Quality
In total, 18 out of the 21 CPC users answered the question “Were there challenges when using the pulse flour?” Ten users indicated that they had encountered challenge(s) when using their pulse flour, whereas five indicated they had not (
Table 8). Among the 10 respondents who reported pulse flour-related challenges, they produced yeast breads (n = 5), snack foods (n = 2), meat alternatives (n = 2), and cookies (n = 1). In contrast, five respondents indicated there were no challenges for snack foods (n = 2), quick breads (n = 2), and thickening agents (n = 1) with chickpea, pea, and bean flours. It was noteworthy that four respondents used bean and chickpea flours for snack foods, and two reported that there were challenges, whereas the other two reported there were not. It was intriguing that some users in each user status category indicated that there were no challenges and that their product was satisfactory. This implies that it is possible to produce satisfactory quality products for some combinations of pulse flour and product type.
Yeast breads were the main product type that pulse flours were used for, and also pinpointed as the most challenging. This high count may be partly because yeast breads were the most selected products that participants have used or considered using pulse flours for (
Table 3). However, the challenges that yeast bread producers reported are useful because gluten formation plays a vital role in yeast bread quality. Gluten is formed during kneading of wheat flour and water, and gluten enables the retention of gas produced during yeast fermentation. The viscoelastic structure of gluten-containing dough leads to high bread volume [
41]. In contrast, pulse flours are gluten-free, and thus, they often present challenges in terms of loaf volume and texture when made into breads [
41,
42]. This survey was designed to characterize the combination of pulse flour and end product as well as the production conditions so that conclusions could be drawn for specific pulse flour types and application. Nevertheless, this was not possible due to the small sample size. Thus, an alternative approach for pulse breeders might be to collaborate with an industry partner to provide feedback on pulse varieties for flours.
The 21 CPC users were asked to select all satisfactory traits of their pulse flour. Texture, appearance, and uniformity were the top three most selected satisfactory characteristics (
Table 9). In total, 63% of the current users were satisfied with product color with pulse flours, while only 25% of the previous and 11% of the considered users were satisfied. This suggests the importance of product color for commercial use of pulse flours. Flavor was selected as satisfactory by all user types, which was surprising considering the deemed challenges with off-flavors of pulse flours described as beany, grassy, and bitter [
39,
43]. This suggests that some food manufacturers know ways to adjust and optimize flavor. Beany flavor may or may not be problematic depending on seasoning used and on the incorporation rate of pulse flours if composite flour is used [
38,
44]. Unpleasant flavors have also been tackled by a plant breeding approach. A commercially available pea protein ingredient was developed by selecting pea varieties that are low in off-flavors [
45].
The 10 respondents who reported there were challenges were asked to select all the product characteristics that they had encountered as issues (
Table 10). Flavor, texture, dough handling properties, mouthfeel, and volume were the most selected challenges. Though flavor was the fourth most selected satisfactory characteristic (
Table 9), 8 out of the 10 respondents selected flavor as a challenge. While texture was the most selected satisfactory characteristic, 6 out of the 10 respondents selected it as a challenge. Texture is a blanket word that encompasses various attributes (e.g., firmness, brittleness, resilience) depending on product types [
46,
47,
48]. Thus, individual research would be needed to address challenges regarding the texture of specific products. As discussed above, dough handling properties and volume are recognized challenges due to the lack of gluten in pulse flours and the resultant lack of or diluted gluten in the dough [
23,
29,
41]. Three of the four votes to “Dough handling properties” as a challenge were associated with yeast breads. Similarly, three of the four votes to “Volume” were associated with yeast breads. Mixing properties were selected by three CPC users who produced snacks, yeast breads, or meat alternatives. Mixing properties include mixing time and consistency measured during dough-forming [
42,
49], and desirable mixing properties may differ for those different end products. A blank comment box was provided to each participant to describe the challenges, but only one left a brief comment about “undesirable taste and texture”. Similar to texture, an individual case study would identify challenges specific to product type. The results obtained from the end-users of pulse flours supported previous findings and highlighted the importance of flavor and texture.
3.6. Variability
The 21 CPC users were asked questions about variability in pulse flour quality by batch or supplier, universal specifications of pulse flour or the lack thereof, and gluten and lectin concerns (
Table 11). Three respondents agreed that pulse flour quality (sometimes) varies from batch to batch, seven disagreed, and ten did not know. Half of the current users indicated pulse flour quality does not vary from batch to batch. One respondent who selected “Sometimes” commented that the quality is “harvest dependent”. In contrast, for variation by suppliers, 11 users agreed that pulse flour quality (sometimes) varies from supplier to supplier. This seems to reflect the current situation in the pulse milling industry, where universal specifications are absent for pulse flours, unlike wheat flour, which results in pulse flour products with varying characteristics milled by the supplier’s own method [
25]. Interestingly, however, not everyone agreed that the variation in pulse flour quality affects their product consistency or that having universal specifications is a critical factor for them. Two respondents who indicated that the variation in pulse flours “sometimes” makes it difficult to produce food products with consistent quality commented that it depends on pulse varieties, growing locations, and weather conditions. These comments showed that some users are aware of the effect of pulse varieties and seasonal conditions on flour quality and, thus, on the food product quality made from it. Regarding universal specifications, one participant who selected “Sometimes” commented that it “Depends on the level of incorporation of the pulse flour in the formulas”, suggesting that specifications may not matter as much if only a small percentage of pulse flour is incorporated in other flours. Fifteen respondents indicated that gluten contamination is (sometimes) a concern in pulse flours, but only six indicated that lectins in pulse flours are (sometimes) a concern, similarly to the bean flour impression results (
Table 5).
3.7. Supply and Logistics
Extrinsic factors such as cost, production, and influence of the COVID-19 pandemic on pulse flour supply were assessed by the 21 CPC users (
Table 12). Twelve agreed that there is a supplier that provides them with their pulse flour at a reasonable cost. The percentage of those who agreed were more or less similar for each user type: 63% of the current users, 50% of the previous users, and 56% of the considered users. It was intriguing that seven agreed that freight cost is a critical factor, but five did not. Eight to ten participants either did not know or did not answer to these questions about supply and logistics. More than half (11) of participants agreed that there is enough supply of pulse flour for their production scale, while none indicated that there is not enough supply. These results suggest that pulse flour supply or cost may not be the main barrier to pulse flour use for food manufacturers. The COVID-19 pandemic saw a surge in sales of pulse products [
50], but only three indicated pulse flour was less available, while seven indicated that the availability is higher or the same.
3.8. Collaboration with Pulse Breeders
Participants were asked if they would be interested in providing opinions to university researchers and plant breeders about how pulse flours can be improved. In total, 9 of the 74 respondents answered yes. Two other respondents left comments that they do not know enough about pulse flours to provide useful feedback or that someone else in the company might be willing to assist. Most of the “yes” respondents were from a single food manufacturer location. Such collaboration will be useful in developing pulse varieties that meet the end-users’ needs and will increase pulse flour adoption. For example, an industry partner was involved in the lab-scale evaluation of pulse flours for crackers, and a selected pulse type (chickpea) was further tested on a commercial scale at the company [
51].
5. Conclusions
An online survey was administered to 75 food industry professionals whose firms produce food products from regular wheat and/or gluten-free flours. The majority of respondents did not use pulse flours. Yeast breads were the most selected product type for which they are using, used, considered using, or would be interested in using pulse flours. Chickpea and pea were the top two pulse flours selected. For the industry personnel who looked for technical information on pulses, scientific associations, both industry and academic, and open-access journals were the main sources. Regarding bean flour in particular, increasing publicity and improving flavor and functionality may be key improvements for inclusion in flour-based food products. Lectin and gluten contaminations were less selected by respondents as concerns. Market demand are likely to be just as important as or more important for continued use of pulse flours than intrinsic characteristics. According to the 21 CPC users, texture, appearance, and uniformity were the three most selected satisfactory characteristics of products using their pulse flour. Ten stated that there were challenges, but five stated there were no challenges. Flavor, texture, dough handling properties, mouthfeel, and volume were the most selected challenges. More than half of the CPC users agreed that pulse flour quality (sometimes) varies from supplier to supplier; however, opinions were mixed about universal specifications for pulse flours and the effect of the variation on the consistency of product quality. Extrinsic factors such as pulse flour supply or cost may not be a main problem to pulse flour users. In summary, flavor, texture, lack of gluten, and market demand were important factors in pulse flour use among food industry professionals who participated in this survey. Individual characteristics that need improvements for specific pulse flour and product type should be studied in future research.