Most people consume far more soy than they think – in fact most of us have an image of soy being something only vegetarians eat. But soy is incredibly high in protein and very versatile so it turns up in a lot more of your food than you may suspect.
Soy beans have been grown for thousands of years in Asia, where they are both eaten whole and used in ingredients such as tofu and soy sauce. But these days most soy is consumed indirectly. The vast majority of soy today is milled into high protein soymeal, which is fed to the animals that we eat.
Soy oil is also used for cooking, in margarines and in other consumer goods, such as cosmetics and soaps and increasingly as a biofuel. And soy derivatives, such as emulsifier lecithin, are used in a wide range of processed foods, including chocolate, ice cream and baked goods.
HOW WE USE SOY
Increasing meat consumption is the main driver behind soy’s rapid expansion. Around 75% of soy worldwide is used for animal feed, especially for poultry and pigs. Between 1967 and 2007 pork production rose by 294%, egg production by 353% and poultry meat by 711%; over the same period, the relative costs of these products declined.
Some 6% of soybeans are used directly as food, mainly in Asian countries such as China, Japan and Indonesia. Whole beans may be eaten as a vegetable, or crushed and incorporated into tofu, tempeh, soya milk or soy sauce. 2% of the meal is further processed into flours and protein additives.
Soy is also used as an ingredient in many baked and fried products, as well as margarine, in frying fats, or bottled as cooking oil. Lecithin derived from soy is one of the most common additives in processed foods, found in anything from chocolate bars to smoothies.
While the vast majority of soy is destined for animal feed, the proportionate economic value of soy oil is significantly larger. So while feed constitutes 75% and oil 19% of the volume of crushed soy (the remainder being byproducts such as soy hulls or waste), the economic value of feed is 57% and soy oil is 36%.
More recently, soybean oil has also been used to produce biodiesel, although this remains a small proportion (just 2%) of the total soy production. Debate continues as to whether or not the fact that the majority of soy is used for livestock feed or human food, and then the remaining oil is used for energy means there is less of a tradeoff between food and fuel than there is with other biofuels.
Interest in soy as a source of fuel certainly is helping to drive expansion in countries such as Argentina where production for 2013 was projected to reach 2.8 billion litres (around 40% its total soy oil production) with most of this exported to Europe.
Soy is predicted to supply about 10% of EU biofuel production by 2020. In the United States, about 3 billion litres of biodiesel annually comes from soybeans, compared with 34 billion litres of corn ethanol. In 2012 biodiesel used 5.7% of the US soy crop.