Soybeans; uses, processing, nutrients and products

Soybeans are members of the pea (legume) family of vegetables and have been a staple of Asian cuisines for thousands of years. Uses f soybeans, its processing, nutrient and products made from it are discussed in this text. Soy and soy foods are popular especially for people following vegetarian and vegan diets. This is due to their high-quality (‘complete’) protein content, and their ability to be processed into milk and meat substitutes.

Soybeans contain hormone-like substances called phytoestrogens that mimic the action of the hormone oestrogen and have been associated with beneficial health effects. Eating soybean-based foods may reduce the risk of various health problems, including cardiovascular disease, stroke, coronary heart disease (CHD), some cancers and improve bone health.

Evidence also suggests the consumption of soy and soy foods is beneficial for peri-menopausal and postmenopausal women and is linked to fewer and reduced severity of hot flushes.

More research is needed, but the evidence so far suggests that it is wise to include whole soy (or soy) foods in your daily diet. See your doctor or dietitian for further guidance.

 Uses of soybeans

Soybeans can be consumed in many ways just like rice. Foods made from soybeans can be divided into unfermented and fermented foods. Unfermented foods include – tofu, soymilk, edamame, soy nuts and sprouts, while fermented soy products include – miso, tempeh, natto and soy sauce.

Over 70 percent of the soybeans grown in the United States are used for animal feed, with poultry being the number one livestock sector consuming soybeans, followed by hogs, dairy, beef and aquaculture.

After harvest, soybeans are either stored in a grain bin or sold to a processing plant, like Cargill in North Carolina. These processors are able to separate the soybean meal from the oil. When processed, a 60-pound bushel will yield about 11 pounds of crude soybean oil and 47 pounds of soybean meal.

Because soy is rich in quality protein and digestible energy, most of the soymeal is turned into animal feed, by baking the protein-rich fiber that remains after the oil is removed. The remainder of soymeal is used to make some soyfoods like tofu and soy milk. The soybean oil that remains after processing out the meal has many uses including cooking oil, biodiesel and bioheat, and non-toxic industrial supplies like paints and cleaners.

Soybeans is also used as a functional food as it gives some health benefits such as lowering of blood pressure, diabetes, weight management etc.

 Cultivation

Growing high-yielding soybeans is best on well-drained, rich in organic matter, loamy soils with a pH of 6.0 to 7.5. This type of soil should be favored above others for a number of reasons. To begin, seeds have a tough time sprouting in saline or sodic soils. Very acidic soils (with a pH below 4.5) are not suitable for growing legumes due to the potential for aluminum and manganese toxicity. Finally, soils with a pH higher than 8 often lack the required micronutrients for growing soybeans, especially zinc and iron .

The shallowness of their roots makes these plants unable to withstand dry growing conditions. So, soybeans do not grow well in soils with poor water retention, such as sand, gravel, or shallow soils. Waterlogging could also be to blame for crop damage. Hence, it is necessary to grow soybeans only in fields with well-drained soil that can still retain adequate moisture for plants to thrive.

 Processing

soybeans can be processed into different food products such as soy sauce, soymilk, local cheese awara, and is used in production on vegetable oil since it is an oil seed.

 Soy sauce processing;

Soy sauce is a Japanese traditional condiment. It has been used for various Japanese foods such as Sashimi, Sushi and Udon noodle soups. Soy sauce products produced in the Kyushu area tend to be sweeter than those in other regions in Japan.

Soy sauce is produced by the fermentation of a mixture of defatted soybean meal and roasted wheat grits, using microorganisms such as Aspergillus, Pediococcus, Saccharomyces, and Candida spp

Traditional soy sauce brewing involves four main ingredients: soybeans, wheat, salt and water.  The breakdown of carbohydrates by yeast or bacteria in the absence of oxygen. Many food products experience fermentation. For example, bread, beer, wine, kefir, kimchi, tempeh, miso, sauerkraut, and kombucha are all fermented food products.

is an important part of the process and the longer the soy sauce ferments, the deeper the resulting flavor becomes. Brewers can take months or even years to produce a batch of high-quality. The characteristics of a product or service that bear on its ability to satisfy stated or implied needs.

At the start of the process, soybeans are steamed, and wheat is roasted then crushed before both are mashed together. This mixture is then inoculated with a specific strain of mould, usually Aspergillus oryzae or Aspergillus sojae, to enable fermentation. At this point, it forms a mash called koji.

The koji is spread out on wooden trays and left to ferment rooms for 2-3 days, and it is during this period of fermentation that starches are broken down into simple sugars, proteins into amino acids, and oils into fatty acids. Long chains of lipids that are found in fats, oils and human cell membranes.

One of these simpler molecules is glutamic acid, which is the amino acid found in Parmesan cheese and mushrooms that gives the soy sauce its umami flavour. The koji also has to be mixed frequently to release the heat produced during fermentation, as the surrounding temperature can greatly affect the entire batch of koji. In some traditional breweries, it was necessary to have a system of air vents, heaters and water boilers to control the overall humidity and temperature of the room while the koji fermented.

 Soybean oil;

To produce soybean oil, the soybeans are cracked, adjusted for moisture content, heated to between 60 and 88 °C (140–190 °F), rolled into flakes, and solvent-extracted with hexanes. The oil is then refined, blended for different applications, and sometimes hydrogenated.

 Soy milk;

Place the soybeans in a blender along with water. Blend until the mixture is smooth. Strain the blended mixture using a cheese cloth or a nut milk bag.

 Nutrients

Soy is a high-quality protein. It is one of the few known plant foods (the other is amaranth seed and to a lesser degree, quinoa) to contain all the essential amino acids, like those found in meat. The soybean is high in fibre.

Soybeans are a good source of several vitamins and minerals, including vitamin K1, folate, copper, manganese, phosphorus, and thiamine and other plant compounds.