It is extracted from slightly dried seeds using chemical solvents. This processing yields an oil whose composition varies depending on the cultivar and time of harvest, but is characterised by a good percentage of omega-6 and omega-3 fatty acids. The beneficial properties of soya oil are best utilised by using it to season raw foods. On the other hand, its instability to oxidation and tendency to form HNE (a highly toxic compound) when high temperatures are reached, make it unsuitable for cooking and absolutely to be avoided for frying.
One of the main properties of soya is the high percentage of vegetable protein it contains (about 40 per cent) and the richness of isoflavones, natural chemical compounds a. Fats, which make up a good 20% of the nutritional composition, consist mainly of unsaturated fatty acids; the amount of carbohydrates is extremely low and the presence of vitamins and minerals is high.
There are different types of soya: black, red, yellow (or green if the latter is harvested before it is fully ripe). The seeds, which are similar in shape to beans, are included in food consumption. They can be used whole – or used as a raw material for dozens of different products. Flavour and texture change depending on how they are consumed and the type of processing they undergo: mostly neutral in the case of flours for human and animal consumption
Also chemically or mechanically extracted from soya beans, it often follows the wording ‘emulsifier’ on the back labels of many industrial products (especially chocolates, bars, creams and pralines). This is because soy lecithin, due to its chemical composition that makes it both lipophilic and hydrophilic, is particularly suitable for emulsions of otherwise immiscible substances such as water and fat. Its wide use by the food industry (especially the chocolate industry) is explained by the fact that lecithin increases the ‘mixability’ of ingredients, which, thanks to its use, are better blended visually and tactilely and are not altered in terms of organoleptic perception.
The starting point is always the seeds that, once ground, yield a flour that can be used in many preparations instead of wheat because, unlike wheat, it is gluten-free. With soy flour, which has the characteristic of being high in protein and low in carbohydrates (carbohydrates and sugars), pastries and biscuits are prepared; mixed with other gluten-free flours, it has also proved successful in bread-making. The high protein content allows for greater water absorption, visibly improves the consistency of the dough and lowers its degree of tenderness once baked.
