Soy Protein Ingredients

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The soy ingredient industry has seen dramatic improvements in both process and application technologies, particularly over the last decade. Food and beverage manufacturers are defining specific issues as they include soy ingredients in formulations.

The soy ingredient industry has seen dramatic improvements in both process and application technologies, particularly over the last decade. Food and beverage manufacturers are defining specific issues as they include soy ingredients in formulations. Meanwhile, soy ingredient suppliers continue to make significant changes to address the functional and performance needs of food manufacturers. Today, soy ingredients not only deliver value in nutrition, function, and cost, but also position flexibility in organics, general wellness, nutrient content, and health claims.


It is still news to many people that soy is a complete protein. In 1989 and 1991, the Food & Agriculture Organization (Rome) and World Health Organization (Geneva) of the United Nations (New York City) issued reports establishing the protein digestibility corrected amino acid score (PDCAAS) method for defining protein quality based on human needs. The Food and Drug Administration (FDA; Rockville, MD) has adopted the PDCAAS method, which is now required as part of food labeling regulations.

Based on the PDCAAS method, soy is the only plant protein comparable in quality to milk, meat, and eggs. Because it contains soy, a smoothie, for example, can now deliver more protein than a glass of milk, and an energy bar can deliver as much protein as a serving of meat-without the saturated fat.


The function and taste of soy ingredients can be strongly affected by what soybean variety is used and how the soy is processed. The commodity soybean supply encompasses any soybean variety, including those that are genetically modified. The identity-preserved (IP) soybean supply can include any soybean variety that has not been genetically modified.

A few soy manufacturers take IP a step further and limit the varieties of soybeans that are identity preserved to a select few chosen for flavor and protein characteristics. At this point, the soybean variety begins to have a direct impact on the taste and performance of foods and beverages.

When the soybeans themselves are organic and the entire production process is certified as organic, food manufacturers have the option of using organic soy ingredients, including concentrates and isolates. Food and beverage manufacturers should consider supply as they respond to the increasing consumer interest in both soy and organic foods.


Soy oil was one of the first soy ingredients used in commercial food applications. The most efficient method for separating the oil is to extract it from a crushed soybean with the solvent hexane. This process yields a defatted, white flake that is the base raw material for the major soy ingredients in use today. Depending on the manufacturer, these defatted white flakes are further processed with other solvents or water to remove carbohydrates and concentrate the protein fraction, making soy protein concentrates or soy protein isolates.

There is another method for manufacturing high-protein soy powders that does not include the use of hexane. This process begins by mechanically pressing the oil from the soybean. Levels of the carbohydrate fractions are removed without the use of solvents to yield high-protein soy powders, concentrates, and isolates. This type of process yields soy ingredients that can accurately be labeled as all natural.Nutriant (Cedar Falls, IA), a business division of the Kerry Group (Kerry, Ireland), took this all-natural process to a proprietary level and had the entire process certified organic. The availability of all-natural and organic soy ingredients can be critical to major brands and retailers as they establish strategic directions in product development. For example, Whole Foods Market (Austin, TX) recently announced that its own branded products will no longer include hexane-extracted soy ingredients.


Food, nutrition, energy, sports performance, breakfast, cereal, weight loss-regardless of the position, the bar category contains many entries characterized by soy, and is continuing to grow rapidly.

Soy suppliers are actively working to address the needs of the bar market. Needs within the bar category include:

  • A variety of alternate textures for both visual and sensory appeal.

  • A soft-extruded core that will maintain a soft texture across the product’s shelf life.

  • Ingredient-based positioning options on fiber, calories, glycemic index, fortification, real fruit, 40:30:30, signature flavors, whole grain, all natural, organic, and qualification as a meat alternative for schools.

New soy ingredients developed to meet these needs include:

  • Whole-grain wheat and soy or whole-grain rice and soy crisps.

  • Extruded soy protein in various shapes, sizes, and hardness.

  • Isolates and isolate systems for core softness.

  • Protein fortified, no-sugar-added fruit and caramel fillings.

  • Whole-grain soy flour that delivers additional fiber for baked bars and can help bar manufacturers and marketers meet the whole-grain claim.

These soy ingredients are naturally low in carbohydrates and can help companies deliver on low-glycemic, balanced, nutrient-content, and wellness positions in great-tasting bars.

An Expert's View of the Soy Marketplace



In the near future, the market for soy foods may be going through some major changes. As the needs of manufacturers have shifted, manufacturing processes have improved, leading to the development of innovative products. In addition, new research on soy’s health benefits has led to the possibility of the Food and Drug Administration (FDA; Rockville, MD) approving a new health claim for soy. Nutritional Outlook discussed the changes in the market and the status of the proposed health claim with Jon McIntyre, PhD, vice president of research and development at The Solae Co. (St. Louis).

How has the market for soy products changed over the past five years?
The last five years has been a time of great growth for soy foods, driven by consumer demand and interest in healthier foods and beverages. During this time, soy food sales have also moved more mainstream. Today, 50% of all sales of soy foods at the retail level occur in traditional supermarket channels, indicating their increasing acceptance among mainstream health-conscious consumers. As a protein source, soy protein is increasingly recognized as a healthful protein source by consumers and is being used more and more in products positioned as “high in protein” or in products specifically positioned around health benefits.

What will the market for soy products look like five years from now?
We believe that in the next five years we will witness tremendous growth in soy products in the marketplace. However, that growth might not be centered in the traditional soy foods category. Today, some of the segments of the market that are showing double-digit growth include snack bars, snacks, yogurts, ready-to-eat cereals, and refrigerated and functional beverages, as well as traditional soymilk. Over the next five years, we believe that soy will continue to find its way into a diverse range of applications, focused on delivering health benefits, great taste, and convenience.

Has FDA responded to Solae’s health claim petition?
The Solae Co. originally petitioned FDA last year for a qualified health claim linking soy protein consumption to a reduced risk of breast, prostate, and gastrointestinal cancers, including colon cancer. The petition is based on nearly 60 scientific studies, which were externally reviewed by expert researchers at top universities such as Harvard, UCLA, and Wake Forest. In April, FDA requested a 60-day extension in the review process for a qualified health claim linking consumption of soy protein–containing foods with a reduced risk of certain types of cancers. As we understand it, the extension is necessary due to a backlog caused by the large volume of health claims the agency is currently reviewing. FDA now expects to make an announcement in late June.

What changes in manufacturing technology have enabled Solae to improve the taste and texture of soy products?
Our Alpha product line, introduced into the market about three years ago, represents a new manufacturing approach to soy proteins, based on membrane processing technology. The resulting products have a different flavor profile versus traditional soy protein isolates that makes them particularly well suited for neutral beverage products and a very viable option for manufacturers looking to replace and/or reduce their reliance on milk proteins in such formulations. We have also introduced a number of manufacturing innovations in extruded products over the last few years that have expanded opportunities for our extruded soy nuggets in nutrition bars, snacks, and ready-to-eat cereals, as well as introduced textural improvements in technologies designed for meat and meat-alternative products.

How has the consumer base for soy products changed over the past decade?
The consumer base for soy-based foods has definitely mainstreamed over the past decade. Ten years ago, most consumers involved in the category were considered “disciples,” highly health-motivated individuals who were committed to a particular health regimen. Today, consumers of soy products represent more-mainstream segments of the population. According to HealthFocus International, more of today’s soy foods consumers are considered “managers,” who are interested in daily health benefits in choosing healthier foods, and “investors,” who are choosing healthy foods to help ensure their future health. Together, these segments represent 64% of the population. They are looking for both health benefits and taste in the foods they choose, and represent a more mainstream view of the benefits of consuming healthier foods and beverages.

What kinds of new health applications are being studied for soy products?
The Solae Co. has a 35-plus-year history supporting research to discover the many health benefits of our soy protein ingredients, and we continue to significantly invest in health benefits research today. Our research has proved the protein quality of soy protein and has enabled the approval of the 1999 FDA soy protein and cardiovascular risk reduction health claim. In addition, epidemiological evidence strongly supports the potential cancer risk reduction benefits of soy consumption and is the basis of Solae’s qualified health claim petition currently under review by FDA. More of our published research has demonstrated health benefits of soy protein consumption relative to women’s health (namely bone health and menopausal symptom relief), performance nutrition, weight management, kidney health, and more. These areas of research offer great promise for the future of soy-based foods, and represent some of the health benefits that are being further explored today.





The baking industry has long made use of soy ingredients, flours, and fibers for their functional contribution to breads. The protein fraction of flour balances variations in the protein content of bread flour, providing a “conditioning” benefit and structure. Soy fiber has extended the shelf life of bread, lowered calorie content, and more recently, enabled fiber and carb content positions.

There remains a wide range of values that soy ingredients can provide to the baking industry, particularly as the labeling requirements for trans fat approach. Specific needs include:

  • Managing the spread in cookies as hydrogenated fats are replaced with no-trans and low-saturated fats.

  • Cost management of nonfat dry milk and eggs in cookies, cakes, and donuts.

  • The extension of fresh-tasting flavor and softness profiles across the now-extended shelf life of breads, base formulas, and ingredients to capture the value of both soy and whole-grain health claims.

Many manufacturers are moving to tropical oils like palm to eliminate trans fat in cookies. However, it remains to be seen if consumers will trade the significant increase in saturated fats that results.

The whole-grain health claim “Diets rich in whole-grain foods and other plant foods and low in total fat, saturated fat, and cholesterol may help reduce the risk of heart disease and certain cancers” offers another great opportunity for food manufacturers to include select soy ingredients.


Another significant challenge has been delivering soy protein that will stay in suspension in a beverage with an acid pH. Success in this category would allow major beverage companies to deliver protein-fortified juices and smoothies that meet the soy protein heart-health claim. This technology would further solidify the juice-based beverage industry’s position in the wellness foods category.

The primary need of soymilks and other neutral ready-to-drink (RTD) fortified beverages is mainstream-acceptable flavoring. While soymilk enjoyed considerable growth when it crossed into mainstream distribution, there is still considerable growth to be had-if it can deliver on flavor.


Terry Gieseke is director of business development at Nutriant (Cedar Falls, IA).