• Soya Products

• Animal Feeds

• Cooking Oils

• Margarines

• Shortenings

• Pet Foods

• Poultry Feeds

• Farm Supplies

INTRODUCTION

In the West, soy foods are being recognized as having a potential role in the prevention and treatment of chronic diseases, most notable cancer and heart diseases. There are also potential roles for soy foods, which include reducing the incidence of osteoporosis, kidney disease, menopausal symptoms, cholesterol reduction (which prevents the development of atherosclerosis) and increasing immunity. The cholesterol reduction ability of tofu was demonstrated on rats on a tofu diet. After one month on the diet the rats' cholesterol levels were lowered. Soya is the most interesting source of protein for the population of the third world. In addition, soya contains high quality oil and important vitamins and minerals.

Protein

In many parts of third world, there is not enough protein for a healthy human diet. The reason may be a shortage of protein but also a poor quality of the available protein, so that it is of little value in the diet. The highest quality protein is found in animal products (eggs, milk, meat, fish). However, these products are expensive and should not be recommended if they exceed the financial capacity of the people. The quality of vegetable proteins is variable and often various vegetable protein sources have to be combined to achieve the desired quality. The soya itself contains a lot of protein: twice as much as most pulses and also twice as much as meat, that is, 30 - 50% of the fresh weight. Moreover, this protein is of good quality, almost comparable to the protein quality of meat. A combination of maize and soya in a 3:1 ratio, in just this combination consumed in one meal, provides a generous quantity of protein of very good quality. A good protein diet is often vitally important, especially for the supplementary feeding of babies, for toddlers and for pregnant and nursing mothers.

Soy protein is highly digestible compared to the digestibility of beef, milk and fish protein. Soy protein contains an excess of certain amino acids, such as lysine, leucine, Valine and tryptoplan. These amino acids are limited in traditional cereal grains, making soy protein a complement to cereal grain protein, thereby improving its nutritional value. Elevated blood lipids have been linked to an increased risk of coronary disease. In a I number of studies done on hypercholesterolemic individuals, replacing animal protein with isolated soy protein reduced plasma cholesterol by a significant amount. These studies demonstrate that soy protein can play a significant role in lowering plasma cholesterol levels. The mechanism for soy protein lowering blood lipids is uncertain, but it has been suggested that soy protein may stimulate synthesis of glucagon leading to a lower cholesterol and triglyceride synthesis.

Oil (15-25%)

The population in the third world often has to rely on starchy, but low-fat foodstuffs (grains, tubers). These may satisfy the energy requirements, but may be insufficient for delivering vitamins, which are only found in fat-rich products (the so called fat-soluble vitamins: Vitamins A, D and E). Soya oil contains Vitamin E and also carotene, which can be converted into Vitamin A. As for Vitamin D, the sunlight ensures that there need be no Vitamin D deficiency in tropical countries, because Vitamin D can be made in the skin under the influence of sunlight. Soya oil also contains a large quantity of linoleic and linolenic acid (polyunsaturated fatty acids), which are considered to be essential to the human diet.

Soybeans contain 20% oil with 85% of that oil unsaturated and 15% saturated. Soybean oil is cholesterol-free, contains 24% oleic acid and is high in two essential fatty acids (55%) linoleic acid and (7%) linolenic acid, the latter fatty acid is not present in most of the other vegetable oils and is important as precursor to prostaglandin. Medical studies have shown soybean oil as useful in the prevention and treatment of heart and blood vessel diseases. Soybean oil also contains approximately 2.5% lecithin, which has been shown to reduce blood platelet aggregation, which is important in the prevention of thrombosis.

Antioxidants

Soya oil, as found in the bean and also in the roughly pressed soya oil (the non-refined form), contains a natural anti-oxidant. Because of this, the oil can be kept well (minimum rancidity).

Minerals

The soya bean, just as most beans and pulses, is rich in minerals (iron and calcium) and vitamins of the B-group namely Vitamin B and Vitamin B2 and nicotinic acid. Most of the carbohydrates in beans and pulses are indigestible. The soya bean contains about 14% digestible carbohydrates.

Soy Fibre

Soy fibre contains 75% dietary fibre, which is a mixture of cellulosic (10%) and noncellulosic (65%). Soy fibre aids in controlling constipation, assists in the management of blood cholesterol and glucose and helps regulate blood insulin levels. In addition, soy fibre does not interfere with the body's optimal utilization of essential minerals, such as calcium, magnesium and iron.

Phylochemicals

Researchers have been able to isolate compounds called Phytochemicals. Further investigations have shown that these compounds are able to protect against diseases in a variety of ways and also have the ability to act as antioxidants, carcinogen (cancercausing substances) deactivators and immune system boosters.

Soybeans have been found to be abundant in many different types of Phytochemicals. Some of them include:

1. Isoflavones. These compounds are similar to natural estrogen and have the ability to help prevent hormone-dependent cancers.

2. Genistein. A compound found only in soy that may stop the spread of some forms of cancer at its earliest stages, as well as helps prevent heart disease. Researchers are investigating this compound as a treatment for prostate cancer.

3. Protease Inhibitors. These arc described as universal anti-carcinogens and may block the action of cancer-causing enzymes.

4. Phytic acids. These compounds have been shown to inhibit the growth of tumors.

5. Daidzein. This is an isoflavone that has shown the ability to inhibit the growth of cancer cells and promote cell differentiation in animals.

6. Saponins. In animal studies these compounds have been shown to kill colon cancer cells.

There is overwhelming evidence that supplementation of human diets with certain soybean products that add these Phytochemicals. could markedly reduce human cancer mortality rate. In a review done on the clinical effects of phytoestrogens, it was found that the applications of phytoestrogens are still in their infancy, but their use offers a safe, cheap and generally side effect-free alternative to current pharmaceutical measures. From the evidence that was reviewed, the conclusions were that phytoestrogens may be among the dietary factors affording protective effects against cancer and heart disease in vegetarians.