Soybean and its qualities

Published: 11/21/2005 - Updated: 08/13/2019

Soybeans (Glycine max L.) are an annual herbaceous plant belonging to the family of Papilionaceas. This is a plant, which has trifoliate leaves of the flowers in axillary inflorescences and fruit pods with 2-4 beans.

Soybeans are native to China, Japan and Korea and was introduced in the Americas and Europe in the eighteenth century. Currently it has a wide distribution in temperate zones. It is estimated that about 80 million acres of 50 varieties of soybean in the world are growing, producing about 180 million tons. At present, the world's leading producer is the U.S., with some 65 million tons, followed by Brazil, Argentina and China.

Nutrition of soybean (100 g raw) 

  • 375 Calories
  • 33g Protein
  • 18 g. of carbohydrates
  • 14 g. of Fiber
  • 20 g. of a fat called lecithin which helps lower cholesterol.
  • Its rich in magnesium, iron (9 mg.), calcium (250 mg.) and especially potassium (1,675 mg.),

remineralizing group, also contains vitamins A, B E and folic acid

Soybeans as a source of protein 

The amount of protein which soy has is approximately 38% (35-40%), but what is its nutritional value? While there is unanimity, on this issue has been discussed its nutritional value. At present, assessment of the quality of the protein is made by the index corrected for amino acid digestibility of protein or PDCAAS (the acronym for Protein Digestibility Corrected Amino Acid Score). This method takes into account both the amino acid composition, determined by a chemical index the degree of absorption. PDCAAS The maximum value that can be assigned to a protein is 1, this value means that after the digestion of food with protein, a protein provides 100% of the amino acids required in the most demanding physiological situations. In this regard, and comparisons between different food proteins has been observed that the PDCAAS of soy protein is very similar to egg white (protein standard), or of beef, about 1. Thus, soy protein is a complete protein, highly digestible, containing all essential amino acids in the reference model in the right proportion.

It is the only grain that provides complete protein. Contains all the essential amino acids that the body cannot synthesize and therefore we must receive in food. These proteins are used by the human body for tissue formation and replacement of worn substances. It is also the cheapest source of protein. Replacing meat protein in their value: 1 kg of soybean is equivalent to 2500 kg of meat, 12 liters of milk, cheese or 2 kg of 5 dozen eggs.

Fats in Soybean

Soybean, being a vegetable food, has no cholesterol, with the benefits this brings for cardiovascular health. The fact that the fatty acid profile present a clear dominance of the unsaturated fraction in turn also contributes to the control of lipemia.
Fats: Saturated 12-15%, 23% monounsaturated, polyunsaturated (linoleic 54%, 8 % linolenic).

Vitamins and minerals 

The calcium-phosphorus of the soybean is optimal, necessary throughout life to growth, bone and tooth development. It contains thiamine, riboflavin and niacin, vitamin B complex factors essential to the development and maintenance of nerves and skin. The grain can germinate in their shoots out a similar amount of vitamin C in tomato.

Isoflavones 

Within herbal substances with estrogenic activity, the most known and studied are the isoflavones. The soybean is a grain of food containing a greater quantity, presenting the peculiarity of being united to its protein fraction. It is estimated that the contribution of isoflavones is 1,3-3,3 mg of isoflavones per gram of protein.

By hormonal mechanisms and non-hormonal (including and highlighting its antioxidant power), has been found that isoflavones have many health benefits. Several studies evaluated the role of these phytoestrogens on fields as diverse as some cancers (breast, prostate, colon), the reserves of calcium in our body, cardiovascular health and discomfort associated with menopause.

Carbohydrates 

The soybean is an excellent source of complex carbohydrates and fiber (30% of total soluble type). This fiber type plays a beneficial role in hyperlipidemia and diabetes mellitus.

It suits infant diet. Milk that is extracted from the grain is easily digestible. For its high value in calcium helps prevent rickets in children. Shown in folks by their content of calcium and protein. Ideal because has a high nutritional value and power of will. Recommended for athletes at the high protein and mineral content in small volume.

The soybean can enter the food supply to more concentrated protein and relatively low cost. Soybeans can be used in food grains, whole or defatted flour or oil. The beans can be used as such. For the preparation of a beverage with properties and appearance similar to cow's milk: soymilk. Whole soy flour should not be stored for long periods.

  • Fresh Grain: used as vegetables (peas, beans, beans, etc.)
  • Dry Grain: used as pulses
  • Sprouts: soybean seeds are germinated.
  • Flour: As it does not contain gluten, it cannot be used alone in the masses of pastry or pasta. Ideally, the ratio of 1 part soy flour and 2 to 3 parts flour. In the case of sauces, pancakes or coated can be used alone.
  • Milk: have a nutritional value similar to that of the cow but does not contain lactose. Can be consumed alone, in preparations for yoghurt and cheese.
  • Oil: is a source of vitamins A, D, E, F, K: the latter as a vital factor in blood clotting. It has a high content of polyunsaturated acids.

About the author
  • Dra. Loredana Lunadei

    Dr. Loredana Lunadei is a specialist in food, dietetics and nutrition. She studied at the University of Milan where she obtained a Master in Food Science and Technology. Subsequently, she continued her studies, completing her PhD also at the University of Milan. Linkedin.