Examination of the nutritional composition of alternative beef burgers available in the United States

Abstract

Alternative meat products provide help to reduce the consumption of meat; however, consumers are concerned with the nutritional quality of the novel and traditional plant-based burgers. The objective is to analyse the nutritional profile of commercially available burgers in the U.S. in the categories of beef, imitation, and veggie. We generated a database of burger products by investigating Mintel and company websites, which resulted in the inclusion of imitation (n = 28), veggie (n = 89), and conventional beef (n = 41) burgers. We analysed the nutritional composition (serving size, kcal, macro and micronutrients, vitamins, and minerals) across the three burger types. Beef burgers provided significantly more calories, fat (total fat, saturated fat, trans fat, and cholesterol), and protein while providing less sodium and fibre compared to alternative burgers. As consumers begin to make conscious decisions to reduce meat consumption, either for health or sustainability reasons, they need to be aware that these products are not nutritionally equivalent.

Keywords:

• Meat analog
• meat substitutes
• novel plant-based meat
• plant-based protein
• nutrition profile
• nutrition label

Introduction

When consumers substitute alternative products in place of conventional meat products, it can positively impact the environment. In terms of food production in the U.S., the beef industry is a primary driver contributing to greenhouse gas emissions and land and water use (King and Webber 2008; Eshel et al. 2014; Heller and Keoleian 2015). Plants have a much lower environmental impact, using 10% of land compared to beef, resulting in only 4% of greenhouse gas emissions (Eshel et al. 2016). Therefore, alternative plant products may be more sustainable and, when substituted for animal protein, specifically beef protein, can significantly positively impact the environment (Goldstein et al. 2017; Ernstoff et al. 2019).

Alternative products contain vegetable and plant-based proteins, with few products having protein sourced from other alternatives, such as algae, insects, and cultured (or lab-grown) protein. Within the plant-based category in the U.S., meat-alternative products have seen the third-highest sales, making just under $1.4 billion in sales in 2020, and seeing a growth of 45% from 2019 to 2020 (The Good Food Institute 2020). This increase in sales mirrors consumer's behaviour, shifting to diets containing less animal-based products. In 2020, roughly 14% of U.S. consumers reported consuming a diet focussed on plants, including plant-based diets, flexitarian, vegetarian, and vegan diets (IFIC 2021). However, some consumers remain apprehensive about consuming plant-based products, with 25.3% of U.S. consumers reporting that they were not at all likely to purchase plant-based meat (Bryant et al. 2019).

In the literature, factors that associate with consumers’ acceptance of plant-based products include cost, familiarity, psychological factors, and cultural appropriateness (Onwezen et al. 2021). From a consumer perspective, the nutritional differences between plant- and animal-based ingredients are a top concern and may discourage them from adopting a plant-based diet. In a survey conducted among U.S. consumers, 41% believe plant-based burgers are better for their health compared to beef burgers (IFIC 2020). In terms of plant-based alternatives for ground beef, consumers are most concerned with sodium content, followed by saturated fat, total calories, and total carbohydrates (IFIC 2020). When consumers are assessing the healthfulness of plant-based ground beef, consumers value vitamin and mineral content the most, followed by cholesterol, dietary fibre, and protein content (IFIC 2020). The nutritional profile is essential when making dietary choices and may determine willingness to substitute meat for an alternative plant-based product.

There are two main categories of meat alternatives or substitutes. Plant-based alternatives, also described as imitation meat, faux meat, or meat analogs, are meant to mimic properties of meat, such as taste, texture, visual appearance, and cooking method. A second category consists of veggie substitutes, which do not claim to taste like meat. Both product types use a variety of ingredients, with differences between imitation meat and veggie substitutes. Historical examples of ingredients include soy, wheat, nuts, and legumes, with advances in technology allowing for more diverse ingredients, including protein extracted from plants (e.g. pea, lentil, and chickpeas) or fungi (e.g. mycoprotein) (Joshi and Kumar 2015; Malav et al. 2015; Ismail et al. 2020). While these ingredients may provide environmental advantages over beef, their nutritional and physiochemical composition deviates significantly from beef, creating challenges for mimicking the nutritional profile of beef products (Gorissen et al. 2018; Loveday 2020; Kumar et al. 2021; McClements and Grossmann 2021a).

When it comes to beef products, researchers and consumers have noted differences in ingredients and nutritional composition between beef and alternative products (Bohrer 2019; Curtain and Grafenauer 2019; IFIC 2020; De Marchi et al. 2021; Harnack et al. 2021). To date, two studies have evaluated the nutritional profile of plant-based burgers, with one study has compared the nutritional quality of imitation burgers (De Marchi et al. 2021) and one examining alternative ground beef (Harnack et al. 2021). De Marchi et al. (2021) selected and compared the nutritional content of three plant-based burgers and four meat-based burgers available in grocery stores in the European Union market. Harnack et al. (2021) examined the nutritional quality of 37 plant-based ground beef alternatives available in the United States and compared the leanness to conventional ground beef. While these studies demonstrate the potential advantages and disadvantages of plant-based products and diets consisting of plant-based foods, prior work has previously focussed on imitation meat and has excluded other vegan alternatives (i.e. veggie substitutes).

Therefore, the present study aims to provide a comprehensive examination of the nutritional profile of both plant-based and veggie burgers and compare the nutritional profile to their conventional product. To achieve this, we identified 158 burger products available in the United States, which resulted in 41 conventional beef and 117 alternative products, which included imitation (n = 28) and veggie burgers (n = 89). First, we compare the ingredients between imitation and veggie burgers, followed by an analysis of the nutritional profile between the three product types. In the present review, we focus on the results based on serving size as specified on the product packaging, as it most closely resembles consumers are following a 1:1 substitution of beef with alterative meat. We anticipate distinctions between categories due to the inherent differences in the nutritional composition of meat compared to plant proteins and the additional ingredients needed to create sensory and textural properties that mimic a beef burger. This work provides new information on the nutritional quality of meat-free burgers, including both novel plant-based and veggie products, and how these sustainable alternatives compare to conventional beef burgers. These findings can help to inform future work related to determining important nutritional drivers for consumer acceptance and consumption, improving the nutritional content of the alternative product to match conventional products, and informing on the potential nutritional implications of consuming a diet consisting of sustainable or plant-based products.

Methods

Data collection

We generated a database of products using a web-based approach and Mintel Global New Products Database (GNPD). The web-based search was conducted between June 2019 to March 2020, which investigated companies’ product portfolios that sold alternative, sustainable, and beef burger products within the United States. Using the Mintel Global New Products Database (GNPD), we used search terms to identify products (i.e. plant-based, imitation, veggie, meat-less, alterative meat, meat analog). After imputing all search terms, the resulting products were independently sorted by two researchers. Products were entered into the database and classified as conventional, imitation, or veggie burgers. Items were first characterised by their product name and ingredient list and then followed a confirmation step through a web search and checking product imaging and promotional language. If products contained only beef as the protein source, it was classified as a conventional product. Products claiming to mimic beef burgers were labelled as imitation. A product was classified as veggie-based on the ingredient list and not advertised as mimicking beef burgers. All products in the database included a complete ingredient list and nutritional fact labels and included no missing values for any of the identified products. The resulting database contains 117 alternative products, including imitation (n = 28) and veggie (n = 89), which were compared to conventional beef burgers (n = 41).

Relevant to the present analysis, the product database includes product and company name, along with nutritional and ingredient information. The nutrients analysed here are required on the nutrition fact panel with several optional vitamins and minerals also included. This includes serving size (g), total calories (kcal), protein (g), total fat (g), saturated fat (g), trans fat (g), dietary fibre (g), cholesterol (mg), sodium (mg), total carbohydrate (g), total sugar (g), vitamin A (% DV), vitamin C (% DV), vitamin D (%DV), iron (% DV), calcium (% DV), and potassium (%DV).

Statistical analysis

For nutritional profiles, we report the mean and standard deviation (SD) for all attributes. We performed a one-way analysis of variance (ANOVA) models to compare the nutritional profiles of the three different product categories. A post-hoc test, Tukey’s honest significant difference (HSD) test, revealed differences between product categories. All analyses were carried out using R (version 4.0.2).

The primary focus is on comparing the nutritional information based on reported serving size (g). Attributes in the analysis include total calories (kcal), protein (g), total fat (g), saturated fat (g), trans fat (g), dietary fibre (g), cholesterol (mg), sodium (mg), total carbohydrate (g), total sugar (g), vitamin A (% DV), vitamin C (% DV), vitamin D (%DV), iron (% DV), calcium (% DV), and potassium (%DV). This nutritional information was analysed as it was reported on the packaging and was not adjusted for serving size.

We performed a secondary analysis to control for differences in serving sizes. For this, we standardised the nutrients for all products based on 100 g. To convert the vitamin and mineral content to milligrams, the percent daily value declared on the nutrition label was multiplied by the recommended daily intake. The recommended daily intake was determined from the U.S. Food and Drug Administration’s (FDA) updated guidelines (Food and Drug Administration 2020).

Results

Comparison of plant protein ingredients

There are 158 burgers in the final dataset, with 117 alternative products, including 28 imitations and 89 veggies which were compared to 41 conventional beef burgers. First, we summarise the sources of protein for all burgers from the list of ingredients. To be included in the summary of ingredients, the ingredient needed to appear in the ingredient list in at least 2% of the products from that product category. All beef burgers contained no other sources of protein other than beef. For imitation burgers, there were four sources of plant-based proteins. Soy was the most widely used across imitation products (53.6%), followed by pea, wheat, and TVP. Few products (<2%) contained rice protein. For veggie burgers, the most common ingredient was rice (46.1%), followed by soy, beans, wheat, mushrooms, quinoa, millet, and TVP. For imitation and veggie burgers, the percentage of products that included each ingredient is in Figure 1. In addition to surveying the portion of products containing specific plant-protein sources, we compared the first ingredient across products. We observed similar trends (not shown), with few deviations. Of note, for imitation burgers, pea protein was the first ingredient for 3.6% of products, ranking fourth, following soy, wheat, and TVP. For veggie burgers, wheat was the fourth most common ingredient, yet was the least common first ingredient, used in 1.1% of products. Overall, veggie burgers contain a greater variety of ingredients compared to imitation burgers.

Figure 1. Percentage of products that include protein-containing ingredients for imitation and veggie burgers. Percentage of products that contain plant-based protein ingredients. Ingredients shown here appeared in at least 2% of products in that product group.

Nutrient comparison

We compared the nutrient composition between the three product categories using a non-standardised portion approach (i.e. assumes 1:1 substitution of beef burger). We performed a secondary analysis that considers standardising amounts to be per 100 g (see Supplemental Table 1). Between the two analyses, there were few differences, and thus, the results will focus on the non-standardised analysis (i.e. based on product serving size).

Serving size, total calories, macro- and micro-nutrients

A one-way ANOVA revealed significant differences for serving size, total calories, total fat, saturated fat, trans fat, cholesterol, sodium, total carbohydrate, fibre, total sugar, and protein content (see Figure 2). For the non-standardised analysis, the serving size of beef burgers was significantly larger than imitation and veggie burgers. There was a significant difference in calories between all three categories, with beef burgers having the highest caloric content followed by imitation and veggie burgers. After adjusting for serving size, the calories remained significantly different between all three categories. For both analyses, the total fat and saturated fat were significantly different between all three product categories, with beef burgers having the highest total fat and saturated fat and veggie burgers having the lowest amount of total fat and saturated fat. Additionally, the trans-fat and cholesterol were significantly higher in beef burgers compared to imitation and veggie burgers for both analyses.

Figure 2. Mean and SD of the nutritional content in beef, imitation, and veggie burgers. Means (±SD) are reported for beef, imitation, and veggie burgers. Analyses were conducted for products based on product reported serving size. One-way ANOVA revealed that all product nutrients were significantly different across product types (p < 0.05). Different letters in the same attribute indicate statistical significance (p < 0.05) determined by post-hoc analyses (Tukey HSD).

For the non-standardised analysis, protein content was significantly different among all three product categories. Beef burgers had the highest amount of protein and veggie burgers contained the least amount of protein. In the analysis standardised for serving size, there was no difference in protein content between imitation and beef burgers, with veggie burgers containing significantly lower protein content than beef and imitation burgers. The total carbohydrate content was significantly different among all three product categories for both analyses. Veggie substitutes had the highest amount of carbohydrates and beef burgers contained the lowest amount. For both analyses, beef burgers contained significantly less fibre compared to veggie burgers and imitation burgers, with no difference in fibre content between imitation and veggie burgers. For total sugar content, the veggie substitutes had significantly more sugar than beef burgers and imitation burgers in both analyses, with no differences in sugar content between beef and imitation burgers. For both analyses, the sodium content was not different between veggie burgers and imitation burgers, and both contained significantly more sodium than beef burgers.

Vitamins and minerals

In both non-standardised and standardised analyses, there were significant differences observed for all vitamins and minerals included in the analysis, vitamins A, C, and D, iron, calcium, and potassium, with varying product differences (see Figure 3). The vitamin A and C content were significantly different across all three product types, with veggie burgers containing the highest content, followed by imitation and beef. For beef burgers, all but four contained no vitamin C. Three had 4% or less the daily value of vitamin C, with one reporting providing 45% per serving. On further examination of the product ingredients, the unusually high vitamin C content was contributed by the inclusion of peppers and rosemary extract.

Figure 3. Mean and SD of the percent daily value for vitamin and mineral content in beef, imitation, and veggie burgers. Means (±SD) are reported for beef, imitation, and veggie burgers. Vitamins and minerals are calculated based on % daily value. Analyses were conducted for products based on product reported serving size. One-way ANOVA revealed that all product nutrients were significantly different across product types (p < 0.05). Different letters in the same attribute indicate statistical significance (p < 0.05) determined by post-hoc analyses (Tukey HSD). Vit: vitamin.

Vitamin D was significantly higher for imitation burgers compared to veggie burgers and beef burgers for both analyses, with no differences between beef and veggie burgers. In the non-standardised analysis, the percent daily value of iron was significantly lower for veggie burgers than beef and imitation burgers, with imitation burgers containing more iron than beef burgers. For the standardised analysis, imitation burgers provided a significantly higher amount of iron compared to beef and veggie burgers. The calcium content was significantly different between the products in both analyses. Imitation burgers had the highest amount of calcium, followed by imitation, with beef burgers containing significantly less calcium. In the non-standardised analysis, the percent daily value of potassium was significantly higher for imitation burgers than beef and veggie burgers. For both analyses, imitation burgers provided significantly more potassium than beef burgers. In the non-standardised analysis, veggie burgers were significantly different than beef and imitation but were not considered significantly different from imitation burgers in the standardised analysis.

Discussion

There are two types of burger alternatives that offer sustainable and meat-free options for consumers looking to reduce their animal intake. According to Mintel database search, there are 117 meat-free burger products available in the U.S. market, with three-quarters of the market meeting the definition of a traditional veggie burger (n = 89) and the remaining quarter consisting of novel plant-based imitation burgers (n = 28). These alternative products provide consumers a way to reduce their meat consumption; however, when making a dietary substitution, it is critical to consider the potential differences in nutritional composition.

There is a trend among the plant-based food industry to substitute animal-based products for more sustainable alternatives; yet, there are concerns that novel plant-based products may not be as healthful (Wickramasinghe et al. 2021). The data presented here provide substantial evidence that alternative burgers provide a nutritional composition that differs from beef burgers. Our findings are consistent with prior work, in that they report significant nutritional differences between traditional animal products and their imitation product (Curtain and Grafenauer 2019; De Marchi et al. 2021), including products mimicking meat (Bohrer 2019; Harnack et al. 2021) and dairy alternatives (Chalupa-Krebzdak et al. 2018; Vanga and Raghavan 2018; Angelino et al. 2020; Clegg et al. 2021). In terms of nutritional quality, imitation and veggie burgers can have a potential positive impact by offering fewer calories, lower fat content (total, saturated, and unsaturated), lower cholesterol while delivering more fibre; however, these products may be considered less favourable in terms of sodium and protein content. Imitation and plant-based alternatives contribute twice as much sodium and provide less protein (10 and 28 g less, respectfully). This is the first study to examine veggie burgers in comparison to imitation and beef burgers, and more work is needed to confirm these differences. Compared to prior work examining imitation burgers, De Marchi et al. (2021) reported imitation burgers offered fewer calories, lower cholesterol, and higher fibre content compared to beef burgers. While there were no significant differences in protein content, there were significant differences in protein quality between the two product types, with imitation burgers containing lower amounts of alanine, glycine, methionine compared to beef (De Marchi et al. 2021), which is in line with prior work (Gorissen et al. 2018). Interestingly, the study did not report on sodium content and reported no differences in total fat content, yet there were significant differences in fatty acid composition (De Marchi et al. 2021). These differences are likely due to the selection of the products, with the current study containing a greater number of imitation products, offering more variability of ingredients. This work suggests that there are not only significant differences in protein and fat content but that the quality of protein and fat vary between conventional and imitation products.

The present analysis identified significant differences in the vitamin and mineral content across products. Veggie burgers offered the highest amount of vitamin A and C, with imitation burgers providing the most vitamin D. However, the vitamin D content in the imitation products was limited to 5% DV, on average. In terms of major and trace minerals, imitation burgers provided significantly more iron, calcium, and potassium, which is consistent with prior work (De Marchi et al. 2021). Of note, zinc and vitamin B12 are two nutrients that were not analysed in the present study but are important nutrients provided in beef products. Prior work reports that imitation products contain less zinc and B12 in imitation alternatives (De Marchi et al. 2021; Harnack et al. 2021). Other minerals not analysed in the present study that may differ between imitation and beef products include phosphorus, magnesium, copper, manganese, among others (De Marchi et al. 2021). There is currently limited data on the investigation of vitamin and mineral content in veggie burgers. While imitation burgers contained more iron, compared to beef, iron from plant sources has a lower bioavailability (Rousseau et al. 2020). Other than iron, beef burgers do not contribute a significant portion of the recommended daily intake of these vitamins and minerals analysed in the present study. Taken together, the present findings and others suggest that consumers need to be aware of the nutritional differences that exist between animal and plant-based alternatives.

While the current analysis does not investigate the relationship between nutritional composition and ingredients, we did observe a greater variety of plant-protein ingredients in veggie burgers (Figure 1) compared to imitations burgers. This could be a result of veggie burgers not intending to mimic sensory profiles of conventional beef burgers, giving more freedom to include diverse ingredients. The blending different ingredients and plant-based proteins help to improve the sensory attributes (e.g. mouthfeel, flavour, and colour) and functional properties (e.g. cookability, texture) (McClements and Grossmann 2021a, 2021b) of imitation burgers. For example, many plant-based ingredients evoke undesirable flavour attributes, such as beany or grassy which can be masked with the addition of sodium, spices, and other enhancers (Fiorentini et al. 2020). On the other hand, imitation burgers, have been described as ultra-processed foods, as they consist of mainly processed ingredients and have a much longer and complex ingredient list than conventional beef burgers (Bohrer 2019). Nonetheless, this limited number of studies provides growing evidence in the literature that distinct differences exist in the ingredient profiles of beef and alternative burgers.

The differences in ingredients are likely driving the differences observed in nutritional content. Here we highlight a few ingredients that may be driving these differences and briefly describe their potential rationale on their inclusion on these products. For example, sodium is significantly higher in imitation burgers, containing 207% more sodium than beef burgers. The addition of sodium can improve the taste and flavour of plant-based ingredients and mask unpleasant flavours typical in plant-based proteins, such as beany and chalky (Mittermeier-Kleßinger et al. 2021). Plant ingredients are generally lower in fat than animal products. However, adding fat to meat alternatives helps to provide desirable flavour and mouthfeel attributes that are comparable to beef burgers. Sources of fat in the alternative burgers examined in the present study include coconut, sunflower, canola, and palm oils; yet, veggie and imitation burgers were significantly lower in total fat, saturated fat, trans fat, and cholesterol than conventional beef burgers. Few imitation and veggie burgers contained other fat sources, including cheese, butter, egg whites, and milk which contributed to the cholesterol in these burgers. Ingredients added to alternative products (e.g. sugar, salt, and fat) to improve the sensory characteristics or physical properties, yet may have a negative impact on the final product's nutritional composition.

This study compares a comprehensive list of three types of burger products that are available in the United States. The strengths of the current analysis are the comparison of beef burgers to two sustainable alternatives, and the comparison of commercially available products, making findings relevant for American consumers. While the nutritional analysis consists of diverse and important nutrients, a limitation to the present study is the lack of nutritional information provided for magnesium, zinc, and vitamin B12, which are important nutrients generally contained in beef products. Very few products provided this information, likely a result of these not being required in the nutrition facts panel. All nutrients analysed here are currently required on the nutrition facts panel, except for vitamin A and C. This area of research is essential, paired with clinical dietary studies, to examine the nutritional dissimilarities between plant-based products and their conventional product, as these differences in composition are likely to have a strong influence over future nutritional diet quality as more individuals adopt diets containing more plant-based foods.

From the present study, we demonstrate the positive and less desirable nutritional differences between beef and two sustainable and meat-free alternatives. Imitation and veggie burgers contain fewer calories, less total fat, saturated fat, trans-fat, and less cholesterol, making these products on average a potentially healthier alternative. However, these products contain significantly less protein and more sodium compared to beef, which may be of concern for some individuals. This study highlights that substituting alternative burgers for beef burgers is not nutritionally equivalent. Consumers have reported that nutritional differences between beef and alternative burgers are one reason for reduced willingness to try plant-based products (IFIC 2020). Yet, other important aspects drive consumer acceptance of plant-based products, such as taste and cost. Advances in research, technology, and processing of plant-based proteins, will allow for a greater diversity of ingredients helping to deliver desirable nutritional, functional, and sensory characteristics of sustainable plant-based products.

Author contributions

N.G.S. and A.N. developed the concept. E.C. and N.G.S. completed the data acquisition. E.C. maintained the dataset. E.C., A.N., and A.C. completed the analysis and interpretation of the data. E.C. and N.G.S. drafted the manuscript with A.N. and A.C. providing revision and intellectual content. All authors approved the final version of the manuscript.

Disclosure statement

The authors report no conflicts of interest.

Additional information

Funding

N.G.S. received funding through The Massachusetts Life Sciences Centre High School Apprenticeship Challenge funded by the STEM@Work Internship Program.