Product developers are hotly pursuing plant-based proteins for new formulations, but their focus mostly has been on legumes and their pulses – soy, lentils and beans. Maybe it's time to look offshore for new sources of vegetarian proteins.
Aquatic plants are gaining interest from more than just health-food enthusiasts. Several varieties of seaweed show potential for providing more and different micronutrients with even less of an environmental footprint.
Lentein powder is made by Parabel USA (www.parabel.com), a Fellsmere, Fla., maker of aquatic food ingredients. Containing 45 percent crude protein extracted from plants in the Lemnoideae family, these sustainable, whole protein sources can grow rapidly in all weather conditions, all year, while requiring little water and no land. Nutritionally, such plants are claimed to contain high levels of all the essential amino acids (those not produced by the body) and branched chain amino acids associated with muscle building.
These free-floating, seed-bearing plants, also called duckweed, are very small, light green and grow in dense colonies in undisturbed water. Fresh or dried, they've been used in Chinese herbal medicine. "Owing to the amino acid composition, the total protein of duckweed qualifies as a high-quality protein source for human nutrition," say researchers in Germany and India.
So far, only a few food companies are trialing plants like duckweed in food applications, but Parabel are other companies are busy cultivating the micro plants. Parabel partnered with Dutch ingredients provider Barentz, which envisions applications such as protein beverages, meat, bakery, pasta, snacks, soups and cold-pressed juices.
"Demand for ingredients like algae, seaweed and duckweed is climbing, as the appetite for pea protein, pulses, nondairy or meat-free alternatives increases," Parabel says. The company says duckweed is free of major allergens such as soy and gluten, and could be one route to a healthier lifestyle.
Algae large and small
Food researchers looking for healthy proteins to use in functional foods may find seaweed's benefits rivaling those of soy beans. Seaweed is on the large end of the algae family. Edible seaweed was typically consumed along coastal areas and has been a staple in Asian diets, often used in soups, seaweed salads and wraps for sushi. Lately, whole seaweed has been added to foods including sausages, cheese, pizza bases and frozen meat products.
The protein-rich, red palmaria palmata species (commonly called dulse or sea lettuce flakes) grows wild on the northern Atlantic and Pacific coasts. The protein content of dulse can vary from 9 to 25 percent, depending on the collection season and harvesting. Resembling red leafy lettuce, dulse is a good source of fiber, healthy fatty acids and antioxidants, and has important amino acids such as leucine, valine and methionine.
Ole Mouritsen, a University of Southern Denmark professor of biophysics, has reviewed the health effects of 35 different seaweed species. One of Mouritsen's articles offers suggestions to the food industry on how to use seaweed to make everyday meals healthier: "Certain substances in seaweed may be important for reducing cardiovascular diseases. We think this knowledge should be available for society and also be put to use."
Seaweed's briny, umami qualities could function as a natural salt substitute, Parabel says. Protein-rich whole algae, such as nori and kelp, is more popular in the U.S. The vegan protein in whole algae is gluten-free and its nutrients are protected by the algae cell wall, which allows it to be used in challenging applications such as low pH beverages, dressings and crackers.
While those are macroalgae and have been food sources for centuries, microalgae is still developing as a food source. Microalgae is 50-60 percent protein and is considered a whole-food ingredient. Depending upon the strain, nutrients can include vitamins A, B, C and E, as well as minerals, fat and fiber.
Considered a super food by some researchers, algae might be one of the world's most overlooked foods. Algae convert energy from the sun into sugars and proteins, absorbing and converting carbon dioxide in the process and expelling oxygen, Several food ingredient providers are offering whole algae and microalgae, which are full of fiber and healthy lipids and micronutrients.
While these ingredients have yet to go completely mainstream at retail, they're finding a place in specialty foods, says the Arizona Center for Algae Technology and Innovation. Spirulina, for one, is being used in food colors as a replacement for artificial dyes and in smoothies and juices, like Naked's popular Green Machine. Protein comprises about 60-70 percent of spirulina's dry weight.
Mind your peas and PDCAAS
Achieving a high PDCAAS, or protein digestibility-corrected amino acid score, is the goal of various ingredient providers developing plant-based protein products. Plant sources generally lack one or more of the nine essential amino acids, which can make it tricky to get all the amino acids the body needs. Plant proteins also face other obstacles: some are only seasonal, some can be costly and many have off tastes, although ingredient providers are working to overcome such challenges.
The source of the protein is key, explains food scientist Regina Bertoldo of Healthy Food Ingredients (www.hfifamily.com), Fargo, N.D. "Plant proteins are a good source of branched-chain amino acids (BCAAs), such as leucine, isoleucine and valine, which promote muscle development and increase endurance. Soy beans have been a plant protein of choice, and are high in leucine but still not as high as whey protein."
Product developers have been limited by formulation challenges, including diminished nutritional values and grainy, chalky textures and bitter or off tastes, notes Jennifer Intagliata, vice president of nutrition at Kerry Ingredients (www.kerry.com), Beloit, Wis. Blending certain plant proteins can improve the PDCAAS, to get closer to that of animal protein, and arrive at tasty formats.
Pulses, legumes and beans are high in protein and fiber and aren't as pricey as some protein sources. Patrick O'Brien, manager of strategic business development at Ingredion (www.ingredion.com), Westchester, Ill., says many gluten-free products fortified with pulse flours are entering the market. "Pulse flours and proteins provide emulsification, water-holding and adhesion, and can offer cost savings." O'Brien says Ingredion is developing clean tasting, clean-label pulse ingredients overcoming the natural beany flavor profiles of some vegetable-sourced proteins.