The ABC’s of Formulating with Plant Proteins
by Alan Rillorta - March 16, 2017
Competition breeds innovation, and nowhere in the ingredients industry is this more evident than in proteins. The ever-increasing popularity of protein foods and expanding consumer demographics is pushing finished product marketers and protein ingredient manufacturers to stay current and open to the many new developments in the market. Plant proteins in particular are booming, due to increasing concern about the environmental impact of animal protein, as well as the growing number of people with special needs diets, and the real and perceived health benefits of a more plant-based diet.
Through the years, protein ingredients have been formulated into almost everything, including powders, bars, cookies, gels, gummies, clear beverages, liquid shakes, soups, breads, nut milks, breakfast cereals, yogurts, ice creams, animal meat replacements and the list goes on. Knowing how to select proteins with compatible characteristics to the final formulation is essential to a successful product development.
Protein ingredient options are vast, ranging from traditional dairy, egg and soy proteins to a new world of emerging plant-based proteins. Within the past few years, there has been a tremendous surge in popularity and availability of a number of plant proteins such as: pea, rice, sacha inchi, hydrolyzed wheat, hemp, coconut, sunflower, pumpkin, cranberry, quinoa, chickpea, potato and algae, among others. How does a finished product manufacturer begin to navigate the many options to determine the best ingredient for a consumer product?
Finding the Balance
This is not a perfect world. Selecting the right protein or combination of proteins to work with depends on multiple variables. Formulating a protein product is a juggling act, where compromises are made between the benefits and disadvantages of several ingredient and manufacturing processes to deliver a product with just enough balance of flavor, smell, texture, visual appearance and marketability while meeting a target price of goods. A plant protein can be a terrific option to satisfy many of these formulation challenges.
Keeping the target consumer in mind when narrowing protein choices is important. For example, the bodybuilding and sport markets tend to favor animal-based proteins. These demographics were around long before the rise of plant proteins and thus have been exposed to many years of marketing focused on animal proteins. The good news is these groups tend to appreciate new scientific research. New data shows plant proteins can be just as effective as animal proteins. Results from a 2013 double-blind study at the University of Tampa demonstrated rice protein and whey protein have identical benefits to muscle building and retention. Similar research conducted on a pea protein also showed its ability to improve muscle thickness when compared to whey protein. Co-formulating lower-priced plant proteins such as pea and rice can counter-balance the higher cost of whey and other dairy proteins.
On the other hand, consumers committed to whole, “natural" foods tend to gravitate toward plant proteins primarily due to their cleaner and more environmentally sustainable image. Incorporating plant proteins into formulations allows the manufacturer to offer the consumer a perceivably “healthier" product. Sprouted brown rice protein, for instance, hones in on marketing hot buttons, specifically sprouted grains and whole grains. Many plant proteins such as pea and sacha inchi are also offered as certified organic, non-GMO (genetically modified organism), gluten- and allergen-free. Additionally, plant proteins such as hemp and algae can have an environmentally friendly image, and are no longer considered “fringe."
Ideally, the perfect protein ingredient would be flavorless, as this would allow the most versatility in custom flavor applications. However, real food, from which natural proteins are derived, have distinct flavor. Even whey, arguably the king of proteins, still tastes like dairy. Soy protein has plant-like, beany notes, as one would expect from a legume. However, through the years, formulators learned to work with these flavor challenges and developed some marvelous innovations.
In many circumstances, proteins are formulated in typically larger proportion compared to other functional ingredients, so their flavors impact the final flavor and texture of a product. For example, pea protein has a thicker mouthfeel and can impart nutty, earthy and savory flavors. Rice protein has a milder cereal-like taste, but can be slightly gritty, rendering poor mouthfeel. Hemp, sacha inchi, sunflower and pumpkin seed proteins all have varying degrees of seed-like nutty and green flavors. Also, many of these proteins can have varying degrees of bitterness. These inherent flavor characteristics can either work to an advantage or disadvantage, depending on the target flavor of the finished product in development. Unfortunately, more often than not, these base protein flavors can be challenging when featured in a neutral flavor base such as in a vanilla.
One way to overcome this is to find a congruent flavor concept in which the flavor of the base protein can contribute to the final formula. Earthy or beany notes work well with nut flavors such as peanut butter, baked flavor like caramel pretzel, or with a chocolate flavor. Astringency can work with citrus flavors as it enhances the flavor. Green notes can provide an added effect with jammy berry flavors that lack greenness to create a balanced strawberry flavor. Bitter notes can blend into chocolate or coffee flavors.
Alternatively, bitterness can be muted by increasing the intensity of the sweetener system or modulating the perception of sweetness through suggestively sweet aromas. This works because the human brain is hardwired to taste sweet over bitter. A little salt can also aid in overcoming some bitterness. Also, there are more advanced technologies that can actually block the tongue’s bitter receptors. Partnering up with a good flavor house familiar with protein formulation early in the process can tremendously speed up the formulation process.
Among other protein formulation challenges is flavor fade. Proteins are good at binding or absorbing flavor. Flavor binding is where the protein folds around a flavor and hides it. In this scenario, more flavor can be used to compensate. Flavor adjustments should also be given some time to re-balance a few days before tasting. Protein flavor binding can also continue well into the product shelf life so any expected flavor loss must be taken into consideration.
There are a variety of textures and mesh size options for plant proteins. Typically, less-gritty and smooth-texture plant protein options are available, although they can be higher priced due to added processing. Ideal protein texture can vary depending on application. As an example, a high-protein ready-to-mix (RTM) powder formulation for the bodybuilder, sport or whole food consumer will compromise on lower-cost options over smoothness to help control consumer price at a tolerable level. On the other hand, formulations targeting taste-conscious mass consumers aiming for a smaller protein serving size might be able to absorb the higher cost of smoother protein options. Ready-to-drink (RTD) formulations pushing above 8 g/8 oz liquid serving can also benefit from an extra smooth protein due to the texture of a protein having a higher impact on a formulation at higher concentrations. Likewise, at low concentrations, a protein’s texture may not be as readily discernable. Certain types of bars and cookies might benefit from a courser mesh protein for mouthfeel.
Mix It Up, Play With It
Furthermore, combining proteins together can help minimize unwanted off-flavors and grittiness. Mixing whey protein with plant proteins can smoothen out texture from any gritty plant proteins. Likewise, plant proteins can balance out the flavor of whey protein where sometimes the dairy flavor is too strong.
Finished product manufacturing conditions can also affect the final texture. Formulating around a protein’s isoelectric point can help proteins stay in solution. A protein’s isoelectric point is the pH level where the protein molecules have a zero net charge. When this happens, there will not be sufficient electrostatic repulsion between the protein molecules to keep them apart; hence, they aggregate and fall out of solution, causing added grittiness. The concentration of salt can have a similar effect where salt present in low concentrations can help with solubility. Salt ions interact with the protein molecules’ ion charge, keeping the proteins from interacting with one another and aggregating. However, overly concentrated salt ions can overpower protein for interaction with water—and the proteins then interact with each other and crash out of solution. Excessive heat can also denature the protein molecules, causing them to aggregate and fall out of solution. Generally, a large majority of available plant proteins aren’t entirely soluble in water, so using stabilizers such as hydrocolloid gums or modified starches can help suspend protein molecules and any other non-protein ingredients for a smoother mouthfeel.
Adding functional ingredients is an easy way to create product differentiation and enhance marketability. There are many options to consider. Collagen, also a form of protein, can give an angle for strong bones and joints, supplementing the active lifestyle image of protein. There are also highly bioavailable forms of magnesium and zinc to consider, as heavy exercise depletes both. Zinc affects protein synthesis and helps to maintain energy levels. Magnesium is a key electrolyte and some magnesium forms have even been shown to help with cognition. Think smart protein! Digestive health is extremely popular right now as well. Adding a probiotic or even better yet, a prebiotic, can help build a healthy gut to effectively digest and benefit from all that added dietary protein.
The prognosis is for the protein—particularly plant-based protein—market to continue to flourish, providing opportunities (and challenges) for the finished product manufacturer. Learning how various proteins work and don’t work is critical to successful product formulation.