It all started when someone sent Savvy Veg a TVP recipe. All I knew about soy protein isolates or TVP is that it's a by-product of soy oil production. I've never knowingly eaten it, but I know it's in just about every processed food, healthy or not, on the market. I decided to do a little TVP research.
Many who can't afford or don't want to eat meat, look to TVP (textured vegetable protein) as a valuable meat replacement, because of its quick cooking, high protein, low fat attributes, and its strong rep as a healthy food.
On the surface, everything looks fine, but there's trouble in soy paradise.
From Wikipedia, The Free Encyclopedia: Dry TVP flakes are an inexpensive protein source when purchased in bulk and can be added to a variety of vegetarian recipes or used as a supplement to bulk out a meat dish. Textured soy chunks are suitable for breading.
Textured vegetable protein (TVP), also known as textured soy protein (TSP) is a meat substitute made from defatted soy flour, a by-product of making soybean oil. It is quick to cook, high in protein, and low in fat.
SV Note: TVP is properly called Soy Protein Isolate, because the soy protein has been isolated from the other parts of the soybean.
TVP is made through a process known as "extrusion cooking". A dough is formed from high nitrogen solubility index (NSI) defatted soy flour and water in a "preconditioner" (mixing cylinder) and cooked during passage through the barrel of a screw type extruder such as the Wenger. Sometimes steam from an external source is employed to aid in the cooking process.
Upon exiting the die, superheated steam escapes rapidly producing an expanded- spongy yet fibrous lamination of thermoplastic soy flour which takes on the various shapes of the die as it is sliced by revolving knives; granules, flakes, chunks, goulash, steakettes (schnitzel), etc., and then dried in an oven. Had the raw material been high in carbohydrates, extrusion cooking could have produced puffed corn curls or puffed wheat.
As a country, we eat far too much protein, and excess protein from whatever source isn't healthy. Lots of cheap soy protein as a substitute for lots of expensive meat protein is still part of an unbalanced unhealthy diet. More about protein and veg diet
Most soybeans grown in the US are genetically modified. Safety testing on GMO food products is grossly inadequate and controlled by the GMO food industry. The few independent studies that have been done indicate serious safety problems. More Info on GMO's
As Wikipedia said, soy protein isolates are a by-product of soybean oil production, processed at high temperatures, using a vast array of machinery. It appears to keep indefinitely in a dried form.
It's a safe bet that, as with most processed food, most of the nutrients except the protein have been processed out of TVP or TSP. There is plenty of evidence that it's toxic in various ways. Does this sound like a natural whole food to you?
"SPI is not something you can make in your own kitchen. Production takes place in industrial factories where a slurry of soy beans is first mixed with an alkaline solution to remove fiber, then precipitated and separated using an acid wash and, finally, neutralized in an alkaline solution."
"Acid washing in aluminum tanks leaches high levels of aluminum into the final product. The resultant curds are spray-dried at high temperatures to produce a high-protein powder. A final indignity to the original soybean is high-temperature, high-pressure extrusion processing of soy protein isolate to produce textured vegetable protein (TVP)."
"Much of the trypsin inhibitor content can be removed through high-temperature processing, but not all. Trypsin inhibitor content of soy protein isolate can vary as much as fivefold. 21 (In rats, even low-level trypsin inhibitor SPI feeding results in reduced weight gain compared to controls. 22)"
"But high-temperature processing has the unfortunate side-effect of so denaturing the other proteins in soy that they are rendered largely ineffective. (23) That's why animals on soy feed need lysine supplements for normal growth."
"Nitrites, which are potent carcinogens, are formed during spray-drying, and a toxin called lysinoalanine is formed during alkaline processing. 24 Numerous artificial flavorings, particularly MSG, are added to soy protein isolate and textured vegetable protein products to mask their strong "beany" taste and to impart the flavor of meat. (25)"
"In feeding experiments, the use of SPI increased requirements for vitamins E, K, D and B12 and created deficiency symptoms of calcium, magnesium, manganese, molybdenum, copper, iron and zinc.26 Phytic acid remaining in these soy products greatly inhibits zinc and iron absorption; test animals fed SPI develop enlarged organs, particularly the pancreas and thyroid gland, and increased deposition of fatty acids in the liver. 27"
Read the full article by Dr. Mercola: Newest Research On Why You Should Avoid Soy
"Soy protein isolate is the most refined form of soy protein and also has the highest soy protein content (90%). It is made from defatted soy meal which has had most of the fats and carbohydrates removed. Because of this, it has a neutral flavor and will cause less gas due to bacterial flatulence."
"Soy isolates are mainly used to improve the texture and eating quality of meat products, but it is also used for other nutritional (increasing protein content), sensorial (better mouthfeel, bland flavor) and functional reasons (for applications requiring emulsification, water and fat absorption and adhesive properties). Specifically, it is used in the following food products: breakfast cereals, energy and protein bars, weight loss ready-to-drink beverages, soups, sauces, baked foods, ice cream, yogurt and other dairy or dairy-free products, meat alternatives and processed meat, poultry and fish products."
"Soy protein isolate is used as a health food as it is a complete vegetable protein containing all the essential amino acids for growth. Also, it has a very low fat content when compared to animal sources of protein, such as meat or milk.
It is also claimed that soy protein isolate may reduce the risk of coronary heart disease and help prevent osteoporosis, some cancers and menopausal symptoms."
"Pure soy protein isolate is used mainly by the food industry and is difficult for the consumer to obtain. It is sometimes available in health stores or in the pharmacy section of the supermarket. It is usually found combined with other food ingredients. Soy protein shake powder, for example, is a mixture of soy protein isolate with flavors, minerals and vitamins."Wikipedia Article Pt. 2 - This Is A Health Food? Pt. 3 - Another Study Has Come To Light