Who would suspect that the protein in mung bean, a simple legume, would be the foundation of one of today’s most successful plant-based alternative foods? The story behind Eat Just’s egg alternative exemplifies the driving forces of plant-based protein products and the sophisticated ingredient technologies needed to bring them to market.
Founded a decade ago, the company is estimated to generate $123 million in annual sales, according to Dun & Bradstreet. Its flagship product, Just Egg, mimics the taste, texture and appearance of yet-to-be-cooked scrambled eggs.
Its ingredient legend lists water, mung bean protein isolate, canola oil, various flavoring and stabilizing components and transglutaminase. The purpose of this last ingredient, an enzyme, is to bind together protein molecules by forming crosslinks between lysine and glutamine amino acids. These “functional mung bean-derived compositions” are protected by the U.S. patent 10,321,705.
The development of Just Egg supports the company’s goal of fixing what the company sometimes calls a "broken global food system." This system is seen as negatively impacting: human health due to nutrition and food safety issues, social issues such as undervaluing farmers around the globe, and environmental and animal issues such as animal abuse, pollution, biodiversity loss and climate change. Efforts to counter these problems often fall under the concept of “sustainability.”
During a presentation at 2021 FIE, Udi Lazimy, global head of sourcing and sustainability for Eat Just, noted the company had sold the Just Egg equivalent of over 160 million eggs, which saved 5.8 billion gallons of water and avoided 23+ million kgs of CO2 emissions.
Needed advances in plant-based proteins
Financial institutions, the food industry and consumers are highly interested if not mesmerized by such developments in plant-based foods and a key component, proteins.
Established protein ingredients such as soy and wheat gluten textured proteins have gradually improved their sensory properties over the decades. When used in skillfully formulated consumer meals, some could easily pass as meats to the casual diner. Practical advances also are being made with multi-functional, high-protein ingredients from other plant sources.
In July 2021, Israel-based ChickP Ltd. announced its protein isolates can work as 1:1 plant-based alternatives for egg yolk in mayonnaise and salad dressings. The chickpea-based ingredients are unusual due to their very high levels of protein (85-92%). “We isolate the protein using our proprietary process that includes functionalization and de-flavoring stages,” says Ram Reifen, founder and chief science officer of ChickP. Enhanced properties include emulsification ability and good heat stability.
Reifen points to formulation advantages offered by protein isolates. The high purity of the proteins means that other needed ingredients can be added in desired ratios. Product developers need not make compromises due to the presence of high levels of components such as sugars, starches and oils. Some of these fractions degrade and shorten product shelf lives, for example, the oxidation of lipids.
“In addition, the high pure protein content permits the formation of a dense protein interaction network that eventually results in a much greater gel and emulsion strength compared to the lower protein load present in other chickpea and pea products,” says Reifen. This allows the formulators to improve the texture more easily in different applications such as meat- and dairy analogues; gluten-free baked goods and other foods that require protein to take part in texturizing their product.
Hurdles in the development of the ChickP protein isolates were significant. A primary challenge was overcoming the taste and odor issues associated with chickpeas, says Reifen. But because the ingredient is 90% protein, there is less of a beany taste typical of legumes or chickpea ingredients with lower protein levels. This off-flavor problem is accentuated in high protein consumer products such as supplements, sport and nutritional applications.
Another major manufacturing challenge of increased concern for many companies is how to deal with by-products. In the case of ChickP, it was the starch and fiber fractions. After some research, ChickP now offers high-quality starch, says Reifen.
Research signals the future
While developments within consumer food and food ingredients bear exciting fruit, a look at projects at research and product development organizations provides insights into future solutions for today’s problems.
The Plant Protein Innovation Center (PPIC), headquartered within the University of Minnesota’s Food Science and Nutrition building, brings together its knowledge of food flavoring components with its growing expertise in plant-based proteins. A project titled “Protein-Flavor Interactions in Food Matrices” is one example.
Gary Reineccius, principal investigator, acknowledges there has been much research into understanding the “temporary” protein-flavor interactions created through hydrophobic, hydrophilic, and ionic bonds. However, little research has been done on covalent bonding that changes flavor profiles in an irreversible manner.
“The implications of covalent reactions are that parts of a flavor will react and be lost while other parts that are not reactive will remain," he says. "As a result, the flavor becomes imbalanced and weakens rapidly during thermal processing and more slowly during product shelf life.”
Working with soy, pea and canola proteins, the project is investigating myriad types of interactions under numerous conditions. Variables such as the functional group under consideration, flavor usage levels, protein structure and amino acid composition, Aw, pH, temperature and the food matrix all impact the rate and type of interaction, says Reineccius.
Related projects look at developing an analytical methodology to measure covalent bonding (with a focus on pea protein) and improving the protein extractability and flavor of pennycress, which is being domesticated as a new eco-friendly oilseed. A completed project has identified key volatile compounds in pennycress’ aroma.
Flavor-protein endeavors are just a few of many food science-based projects underway. Others include efforts to improve extraction of protein from plant materials as well as modification of proteins for improved functionality, nutritional value and decreased immunoreactivity, to name a few. For more information, visit the University of Minnesota's Plant Protein Innovation Center.
As the commercial sources of plant proteins proliferate, investigators can more easily compare their functionality and characteristics within an application. Researchers at Texas A&M University have investigated the use of peas, lentils and faba beans in high moisture meat analogues.
The goal of one study by T. Kim, et. al. presented at AACCI’s 2019 Cereals & Grains Conference, was to evaluate certain taste and textural attributes of high moisture meat analogues (HMMA), i.e., hamburger-like patties, made from pulse proteins and extruded using a twin-screw extruder.
The experimental systems under study were composed of 15% wheat gluten, 6% canola oil and one protein treatment for a total of 73% protein. For the control, the protein treatment was a mixture of soy concentrate and soy isolate. The other protein treatments either used commercial pea protein (55.4% protein), lentil protein (55.4% protein), or faba bean protein (61.5% protein). Pea isolates of 85% protein were also included in each.
The details of the research can be read here bit.ly/3GzOO6l. The study concluded that pulse proteins can be an alternate source of soy in HMMA. Consumers had a similar liking for the samples using the different pulse proteins. Their cooking times were shorter and yields higher than the control. However, patties made from the pulse proteins were lower in cohesiveness and gumminess. To correct this, food formulators have found additional ingredients such as hydrocolloids to be beneficial.
More recent studies at Texas A&M by the same researchers have looked at the impact of cooling and rehydration methods of HMMAs. Another project further delved into the sensory desirability of HMMAs that contained added spices, binders, etc.
Commercial offerings of plant-based meat alternatives have grown rapidly in number. Julia Thompson, Culinologist III at CuliNex, a food product development consultancy specializing in clean label and plant-based formulation, offers real-world advice when choosing plant-based ingredients: “The first thing we consider when formulating a plant-based burger is the texture and bite of the plant-based protein.”
It is very difficult, but not impossible, to change the mouthfeel and bite of textured plant protein ingredients, so finding the right one with which to start is critical, she says. The majority of plant-based meat analogues get most of their final texture from textured proteins. “For a burger application, we are looking for something that is bouncy with a snappy bite that can hold water well without being too spongy.”
Another big factor is the ingredients’ impact on the globe, their human impact and the stability of their supply chain. “Like our clients and their consumers, we have a mission to have a positive impact on the planet,” says Thompson.
Many consumers buy plant-based meat alternatives because they believe that they are choosing more sustainable food. “We aim to deliver on that by selecting the most sustainable proteins with consistent availability for all our plant-based development projects.”
Progress in performance
A dizzying array of plant-based consumer foods striving to mimic protein foods are being launched into the marketplace.
Nizo, a research organization headquartered in the Netherlands, uses a pyramid model to demonstrate the different stages, or generations, of products in the plant-based protein foods category. Fred van de Velde, expert group leader-protein functionality, used vegan cheese as an example of technical developments in foods designed to replicate traditional animal-protein products:
- 1st Generation: The first level of the pyramid concerns technical performance. For example, vegan cheese should be yellow and safe to eat. Products ought to have a good sensory profile that should not be sacrificed as further improvements are made.
- 2nd Generation. This level involves technical functionality. “The vegan cheese should be sliceable and should melt on the pizza,” says van de Velde.
- 3rd Generation. The food should have the same nutritional profile as the food being mimicked. The first vegan cheeses were usually based on starch and fat.
These foods should strive to be on parity with desirable components such as protein and vitamins.
- 4th Generation. At this final stage, products should also be clean label and consist of sustainable ingredients.
However, not all consumers want as perfect a replica of “the real thing” as possible. “We start every project with a careful dialog about the client's objective and consumer target profile,” relays Thompson. Some of CuliNex’s clients target consumers that eat beef but are looking for a plant-based, sustainable alternative. “For them, we develop a product that mimics beef texture and flavor as closely as possible, using the newest available technology,” she says.
Alternatively, CuliNex has clients that would like their products to taste more like plant-based ingredients designed with traditional vegetarians or vegans in mind who enjoy the flavors of plant-forward foods. “Here we are directed to develop a product with less processed ingredients,” Thompson says.
Satisfying such vastly different preferences of consumers will give product formulators challenges and opportunities far into the future.
