R&D spotlight: Textured soy protein
Most of the new soyfoods entering the market place contain textured soy protein, also called TSP (or textured vegetable protein, TVP). Textured soy protein can be made from soy flour, soy concentrate or soy protein isolate, but only textured soy flour is readily available for consumers to buy.
The wide array of soy protein ingredients, when rehydrated, resembles cooked ground beef or poultry in texture and may be used alone or with meats to make a wide variety of products.
Textured soy protein (TSP) may be unflavored, meat or chicken flavored, and appear in chunks, slices, flakes, crumbles or bits. Many convenient, dry entrée mixes include textured soy protein with additional herbs and flavorings.
In the kitchen
One cup boiling or hot water, broth or stock poured over 1 cup of small granules will reconstitute in five to 10 minutes. For larger chunks or slices, use 2 cups of liquid to 1 cup of chunks/slices and simmer for 20-30 minutes until tender, but not mushy. TSP granules or flakes can be rehydrated in a microwave by covering the moistened granules and cooking on high for about five minutes.
A pound of TSP will equal about three pounds of ground beef. One cup dry TSP reconstituted in 1 cup liquid yields about 2 cups. Unflavored textured soy protein easily assumes the flavor of other liquids and foods. It combines well with ground meat or poultry, or can appear alone in favorite recipes.
Unflavored textured soy protein will last indefinitely if stored in a dry, airtight container. Stored the same way, flavored TSP will last at least one year. Both can be available for use at any time. Once rehydrated with liquid, TSP should be refrigerated or frozen until used. Refrigeration preserves the reconstituted TSP for only a few days and freezing preserves it for 3 to 6 months.
Textured soy protein is at least 50 percent protein. Unflavored textured soy protein is very low in sodium. Textured soy protein is an easy and inexpensive source of dietary fiber, soy protein and naturally occurring bioactive components, such as isoflavones. Isoflavones are being studied in relationship to relieving menopausal symptoms, maintaining healthy bones, and preventing prostate, breast and colorectal cancers. The content and profile of bioactive components varies from product to product, depending upon how much soy protein is in the food and how the soy protein is processed.
Textured soy protein is a healthy high-quality protein source that contains all essential amino acids needed for growth. This protein comes without cholesterol and with little or no saturated fat.
In addition to the quality of soy protein, scientists have found that soy protein may help reduce the risk of heart disease by lowering blood cholesterol and increasing the flexibility of blood vessels. The FDA has approved a health claim stating that “25 grams of soy protein in a daily diet low in saturated fat and cholesterol can help reduce total and LDL cholesterol that is moderately high to high.” NP