Pumping Up Plant Proteins: Formulating for
Vegetarians, Vegans and “Flexitarians”

By Mark Crowell, CRC


Today most consumers are looking for quality protein sources, but with movies like “Food, Inc.” highlighting issues surrounding conventional livestock and celebrities like Ellen DeGeneres announcing that they have converted to veganism, more consumers are seeking out plant-based proteins.

This trend has been building for some time. In a 2006 survey conducted by Harris Interactive, 2.3 percent of adults 18 years or older said they were vegetarian with 1.4 percent identifying themselves as vegan. Even more significant, a much larger group, perhaps 25 to 30 percent of the population, identified themselves as “flexitarians.” A flexitarian is a part-time vegetarian who eats three or more meatless meals per week. Their focus is more likely on personal health than animal rights, but many use their meatless meals to explore new cuisines, ingredients and cooking techniques, giving product developers broader leeway to be creative.

Research shows that weight management and cost concerns are two of the top reasons consumers choose a vegetarian diet, but one-third of consumers make the switch due to environmental concerns and/or vegetarian principles. Consumers are becoming more aware of the environmental costs of meat production—from increases in greenhouse gases to deforestation. Today, more than 70 percent of all grains grown in the U.S. go to feed livestock. According to David Pimentel, Professor of Entomology, Cornell University, if all that grain was consumed directly it could feed an additional 800 million people.

The Role of Protein
Protein is the basis of all bodily needs, from hair development to muscle mass. It’s critical to life and, within the body, it’s second only to water in abundance. About half of the body’s protein is found in skeletal muscle. The rest is found in organs, blood, enzymes and hormones.

While carbohydrates and fats have been maligned by diet faddists, protein is the only macronutrient that no one can seem to find fault with. Proteins consist of amino acids and the human body uses amino acids acquired from the diet to build its own proteins. There are a total of 21 amino acids, eight of which are essential because the body cannot produce them from the diet. Meat and eggs contain all the essential amino acids and are thus said to be complete proteins, while many non-animal foods contain small amounts of some amino acids and are referred to as incomplete proteins. Exceptions include hemp seed, soy, quinoa, amaranth, chia, buckwheat, flax, spirulina and chlorella—all of which are considered complete vegetable proteins. Therefore, by incorporating a variety of foods into their diet each day, vegetarians can easily get all of the essential amino acids they need.

A high-quality protein is not merely complete. It contains the essential amino acids in amounts proportional to the body’s need for them. It’s also digestible, so that sufficient numbers of these amino acids reach the body’s cells to permit them to make the proteins they need. Currently, the most accepted measure of protein quality is the Protein Digestibility Corrected Amino Acid Score (PDCAAS). Scores of 1.00 indicate that a protein contains all the essential amino acids necessary for humans in a bio-available form. Whey protein, whole egg, casein and soy all have a PDCAAS of 1.00. The usual recommendation is about 0.8 grams of protein per kilo of body weight a day, which is about 56 grams for someone weighing 70 kilos (154 pounds). Pregnancy, breastfeeding, high levels of physical activity and illness can increase these requirements.

Protein is also important to counteract aging. By 2030, almost 25 percent of the U.S. population will be 65 or older. Aging causes a 3 to 8 percent reduction in lean muscle mass every 10 years after the age of 30. As it ages, the body’s ability to convert amino acids into muscle tissue becomes less efficient. However, research suggests that consuming higher levels of essential amino acids might rev up muscle building and halt or reverse the loss of muscle mass.

Protein also stands out as a key macronutrient in the war against weight gain. Both animal and human studies show that consuming protein, as compared to carbohydrates and fat, promotes feelings of satiety and suppresses food intake at the next meal.

Proteins for Meatless Diets
For product designers, the addition of protein in a formulation is a critical decision that should be based on several factors, including use of other ingredients and overall protein target level. So let’s look at some of the plant-based choices.

Grains and Seeds
A number of grains and seeds stand out as high-quality protein sources. Here are a few.

Quinoa. This seed has been an important food for more than 5,000 years, particularly among pre-Columbian Andean civilizations including the Incas. For an ancient food, however, it’s getting decidedly modern attention. Due to its health profile, it’s being considered for NASA’s controlled ecological life-support system for long-duration manned spaceflights.

In South America, quinoa is used as a replacement for rice. It can be milled for bread (kispina) or can be popped like popcorn, called “kokitos.” In Chile, roasted, ground seeds are mixed with sugar, warm water, milk or fruit punch. Perhaps picking up on this tradition, last year Newport Quinoa Company introduced a range of quinoa-based beverages.

For formulators, quinoa is available as pearls (a larger grain, often used in soups), puffs (used for cereal or as a sweet topping) and flour, which has a protein content of about 14 percent. Quinoa is gluten-free and can be combined with sorghum flour, tapioca and potato starch to create an allergen-free baking mix.

The sweet flavors of quinoa pair well with brown or palm sugar, peanuts, almonds, Brazil nuts, coconut, cassava and dried fruit powders. The savory flavors pair well with milk, lime, cilantro, mint, jalapeno garlic and onion.

Chia. Made famous by “Chia Pets” in the 1980s, chia seeds are now known for their impressive nutrient profile. These seeds are rich in omega-3s, antioxidants and fiber and boast 20 percent protein, including all the essential amino acids. Chia’s use as a high-energy endurance food has been recorded as far back as the 13th century. It was said that Aztec warriors subsisted on chia during conquests.

Chia seed may also have potential for improving long-term cardiovascular risk factors in type 2 diabetes, improving insulin sensitivity, lowering levels of triglycerides and low-density lipoprotein cholesterol, and increasing the level of high-density lipoprotein cholesterol. It works well as a flour substitute and because it is hydrophilic, chia has the ability to absorb liquid and form a gel—making it a great thickening agent. Chia’s jelling ability allows it to form a physical barrier between carbohydrates and the digestive enzymes that break them down, thus slowing the conversion of carbohydrates into sugar, a benefit to diabetics and endurance athletes.

Amaranth. Another ancient grain, amaranth boasts a protein level of 16 percent and like quinoa is gluten-free. In Mexico it’s popped and mixed with a sugar to make a confection called “alegria” (happiness). Peruvians use fermented amaranth seed to make “chicha” or beer. In India amaranth is known as “rajeera” (the King’s grain).

Today, more than 50 products containing amaranth are currently on the market in the U.S. The seeds are processed by boiling, swelling, flaking, extrusion, puffing, roasting, grinding and sprouting. Whole amaranth seeds are used in a variety of products, but amaranth flour is the most common ingredient. It must be mixed with other flours for baking yeast breads since it doesn’t contain gluten.

Flax. Flaxseed was cultivated in Babylon as early as 3000 BC, but is today experiencing a renaissance among nutritionists, the health-conscious, food processors and chefs. Flax contains all sorts of healthy components but owes its reputation to high levels of omega-3 essential fatty acids, lignans (which have both plant estrogen and antioxidant qualities) and fiber. Less well known is that flax is 22 percent protein and readily available as organic whole or hulled seed or meal. Flax is commonly used in bakery, dressing, cereal and beverage applications.

Sprouted Grains
Popularized by the raw foods movement, proteins derived from sprouted grains are being seen in more products. Sprouting generally increases the bioavailability of essential amino acids, enzymes, vitamins and fiber, making them more nutritionally dense and digestible. Food For Life has had sprouted grain products out on the market for years, and the company says its blend of sprouts parallels proteins found in milk and eggs. Garden of Life recently launched an organic, raw, vegan protein powder made from 14 types of sprouts that include sprouted brown rice, amaranth, quinoa, lentils, pumpkin seeds, flax seeds and garbanzo beans. All this adds up to a protein content of 75 percent, containing all essential amino acids, and totaling 18 grams of protein per serving. The product is allergen-free.

Many other seeds, beans and grains can be sprouted including alfalfa, mung bean, broccoli, mustard seed, buckwheat, chia, crimson clover, fenugreek, wheatgrass and barley grass. A 1-pound bulk package of seeds yields 6 pounds of sprouts.

The Many Faces of Soy
Few products are as versatile or have as long a history of consumption as soy. Soy proteins rate a perfect 1.00 on the PDCAAS scale, containing all essential amino acids. And, while soy is nutritionally comparable to egg, milk and fish, it’s typically the most cost-effective protein ingredient.

Soy gets high marks for lowering cholesterol, decreasing blood glucose levels and improving glucose tolerance in people with diabetes, according to a new study from the University of Massachusetts Amherst. Researchers identified the molecular pathway that allows foods rich in soy bioactive compounds (called isoflavones) to lower diabetes and heart disease risk. Due to scientific findings like this, soy has an FDA-approved health claim. If the product contains 6.25 grams of soy protein per serving and meets other health requirements, a claim for a reduced instance of cardiovascular disease can be made.

Soy-based protein products range from soy flour and tofu to miso, soy nuts and tempeh. One cup of cooked soybeans or tempeh contains around 30 grams of protein, while 1 cup of firm tofu contains about 25 grams of protein, about one-half of the daily adult protein recommendation. Soy is also the most common ingredient in textured vegetable protein, or TVP. TVP is available as flakes, granules and chunks, which have a fibrous, spongy texture similar to meat.

There are organic versions of full-fat and low-fat soy flour as well as soy bits, pieces and “nuts” (roasted soy beans). Soy isolates are 90 percent protein, while soy concentrates are around 65 to 70 percent protein. Soy flours are in the 50 percent protein range. Soy flour can also be used in baked goods as an egg replacer. Mian Riaz, Ph.D., director, Food Protein R&D Center, Texas A&M University and consultant to the United Soybean Board explains, “Some enhanced-trait soybeans now contain very little lipoxigenase enzymes, which are responsible for ‘beany flavor.’ As a result, manufacturers are able to use soybean ingredients with very neutral flavor in their food products in order to reap the benefits of protein’s satiety effect and all the benefits of heart-healthy soy protein in particular.”

Even sports nutrition is seeing an upswing in soy usage. A study published in the Journal of the International Society of Sports Nutrition found that “Soy protein was just as effective as whey in its ability to help weightlifting males gain muscle.”

When formulating, keep in mind that soy protein is not as soluble as dairy proteins. For beverages, use of an isolate versus other soy ingredients is more typical because of the higher protein content. The pH of the beverage system will determine the exact soy protein to use in order to provide minimal viscosity changes.

A common strategy in the nutrition bar market is to use soy protein in conjunction with dairy proteins, such as whey protein or caseinate. Often, developers find that ideal texture, taste and cost are achieved by combining proteins. This is particularly true when targeting very high levels of protein.

In addition to isolates, soy can be added to prepared foods via tofu or miso. Tofu is a complete protein containing all eight essential amino acids; it has 10.7 percent protein content if firm and 5.3 percent if a soft variety.

Miso is also a complete protein, containing up to 32 grams of protein per cup, and can be used as a thickener for soups as well as a seasoning for sauces, marinades, salad dressings and dipping sauces. As a general rule, lighter misos are sweeter and younger and contain less salt; darker misos are thicker and saltier and have been aged longer.

The isoflavones found in fermented soybean foods such as miso are more readily absorbed by the body and can aid digestion. Today there is also chickpea miso available for those allergic to soy. Freeze-dried miso is a popular choice for dry soup packets as well.

Two new studies have shown that fermenting soy can reduce allergenicity by 99 percent while improving the amino acid profile of the product. Studies are ongoing to understand if soy phytoestrogens disrupt the endocrine function or have any impact on fertility or breast cancer in adult women. Studies have also indicated that the vitamin B12 analogs in soy are not readily absorbed and that soy foods may increase the body’s requirement for vitamin D, a current hot-button topic.

Pulses and Legumes
Pulses are the dried edible seeds of legumes and include peas, lentils, kidney beans, chickpeas and many other bean varieties. They boast 20 to 30 percent protein on a dry-weight basis and are rich in lysine—the amino acid missing from most grains.

Pulses have wide-ranging functionality and are known for their solubility, emulsifying properties, good lipid affinity, foam stability and water-holding capacity, as well as enhancing structure and nutrition in many products.

Peas, lentils, chickpeas and soybeans can be fried, roasted, baked and extruded to create many snack foods. Crushed lentils are often used in instant dry soup mixes and packaged entrées. Whole bean powders can be used in bakery items, dips, salads, dry soup mixes, or as natural thickeners or meat binders. Organic roasted split peas can add a healthy crunch to trail mixes, snacks, bars and cereals. One cup of cooked pulses contains about 15 grams of protein. Pulse flours add fiber and protein to breads, pastas, breakfast bars and other baked goods, are excellent flavor carriers and can improve crispness, volume and appearance.

Gluten-free, pea protein has become a popular choice in vegetarian foods as a non-allergenic alternative to soy. Weight-control shakes can incorporate up to about 6 percent and sport-nutrition shakes up to about 14 percent. Within protein bars, levels can go as high as 17 percent. Pea protein has a slight vegetable taste, but a minimal impact on final flavor. The yellow pea flour is beige with the color of concentrates and isolates being closer to neutral.

Pulses have recently been the subject of a number of studies related to colon health, diabetes, weight management, prostate cancer and macular degeneration. Pea protein has a PDCAAS score of 0.86 because it’s low in the amino acid tryptophan, but it has excellent digestibility comparable to animal proteins. One gram of pea protein can bind 4 grams of water or 17 grams of oil.

Hemp
Hemp is a trendy ingredient right now, but it certainly isn’t new. China cultivated it more than 6,000 years ago, long before soy. Although the hemp plant is related to marijuana, it has almost undetectable levels of tetrahydrocannabinol (THC), therefore it won’t make you high.

It could make you healthier though. Hemp protein powder contains 50 percent protein, 20 percent essential fats (with the preferred 3:1 ratio of omega-3s to -6s) and 13 percent fiber. Like pulses, hemp is a non-allergenic, easily digestible plant protein and an excellent alternative for those with sensitivities to soy. Hemp is complete protein and has a PDCAAS score of 0.46. It is often best to combine it with other sources of protein like pea or rice, which complement it nutritionally and functionally. In protein supplement products an animal source like whey, which is very fast-acting on muscles, can complement hemp, which has long staying power.

Vital Wheat Gluten
Despite a growing awareness of gluten intolerance, the majority of people still eat wheat-based products. Vital wheat gluten can be up to 75 percent protein by weight. Wheat gluten, or seitan, is a food made by washing wheat flour dough with water until all the starch dissolves, leaving insoluble gluten as an elastic mass, which is then cooked. Gluten is bland and light in color, offering product developers the option of coloring and flavoring it to mimic meat. It has a fibrous nature and meat-like structure which strings apart similar to chicken.

Gluten is available in blocks, strips and shaped forms, which are commonly used in meat analogues. Wheat proteins are used in pasta and snacks to enhance extrusion. In bread, gluten helps compensate for low-protein flours and supports heavy particulate ingredients like cracked grains, nuts and dried fruit. In cereal products, gluten can bind vitamin or mineral enrichment components to grains, and improve the strength of flakes.

Algae
Chlorella and spirulina were used as dietary supplements in the early 1900s, before synthetically produced and purified vitamins and minerals became available. Today, people supplement with algae to help lose weight, increase energy, improve mood, prevent heart disease, boost the immune system, and inhibit oral cancer. For this last benefit, there have been some relatively strong studies in spirulina’s support. Spirulina and chlorella seem to be the most popular of the micro-algae green foods and because they are whole organisms, they contain a wide spectrum of nutrients, including all the essential amino acids needed for protein as well as vitamins, minerals and essential fatty acids.

Overall, when working with plant-based proteins, your choice of organic ingredients and product forms is broad and continually improving. So choose wisely to take full advantage of plant protein’s nutrition, health benefits and functionality in your next formulation.

Mark Crowell, CRC, is the founder and principal culinologist at CuliNex, a consultancy specializing in the development of organic and natural food products. He is the former director of product development for Olive Garden Restaurants and Starbucks Coffee Co. CuliNex specializes in assisting food manufacturers, ingredient suppliers and multi-unit foodservice operators achieve their growth goals by developing and bringing successful products to market. You can reach Mark at mark@culinex.biz.