"Soya" (or "Soy" in the United States), is a legume, Glycine max (L.) Merrill. Soya has been grown for three millennia in Asia and, more recently, has been successfully cultivated around the world. Today, the world’s top producers of soya are the United States, Brazil, Argentina, China and India.
About 85 percent of the world’s soyabeans are processed, or "crushed," annually into soyabean meal and oil. Approximately 98 percent of the soyabean meal that is crushed is further processed into animal feed with the balance used to make soya flour and proteins. Of the oil fraction, 95 percent is consumed as edible oil; the rest is used for industrial products such as fatty acids, soaps and biodiesel.
Soya is one of the few plants that provides a complete protein as it contains all eight amino acids essential for human health.
Because soybeans are grown around the world under many different climatic conditions and have been grown for many centuries, there is wide range of soyabean varieties. Genetically modified (GM) soyabeans varieties began to be commercially grown in 1996, and they quickly became predominant in the major soya producing countries. Early GM soyabeans were engineered to be herbicide resistant (specifically to the popular RoundUp Ready brand glyphosate) and were thus very popular with farmers. More recent generations of GM soyabeans have included traits that have benefits for oilseed processors and the consumer. Seeds containing more that one of the attributes is said to have “stacked traits.”
With the dramatic increase in GM crops over the last decade, soyabeans that have been bred traditionally have become increasingly valuable for use in the European Union and other areas particularly sensitive to the use of genetic modification. Traditional varieties are also used in organic foods and other products for which the consumer expects a ‘natural’ product.
Some soyabeans are larger in size and higher in protein than others, while some varieties have a brown, buff or clear-colored hilum (the spot on the soyabean where it connects to the pod). Soyafoods manufacturers require different types of beans for each product; for example, producers of the traditional Japanese soyafood ‘natto’ need a small soyabean variety with a thin seedcoat and high carbohydrate content.
In order to ensure the integrity of the finished product, food makers and others who have specific requirements may purchase Identity Preserved (IP) beans. This means that details about the identity and origin of the crop is tracked from the farm all the way to the finished product. Organic and IP soyabeans command a premium in the marketplace because of the additional work involved.
Brief Overview of Modern Market
The first written reference to soya appears in a list of Chinese plants from 2853 B.C.; it is also referred to many times in ancient writings as one of the five grains essential to Chinese civilization. Western contact with soyabeans and soyafoods was limited until Asians began to emigrate in large numbers to Europe and the U.S. in the 1800s.
Common Processing Methods
After being cleaned and dehulled, one of three processes is used to separate the soyabean oil from the protein meal (this is also called "crushing" or "oil mill" operations).
These processes are: