Influence of grain raw material particle size on the functional value of food products obtained on its basis (review)

The aim of the work is a brief analysis of the English-language scientific literature on the effect of grain size on the nutritional and functional value of products obtained on its basis. It is established that the size of grain particles is one of the main parameters that should be taken into account when considering the nutritional and functional value of the products obtained from them. It has a direct effect on the distribution of phenolic acids, proteins, carbohydrates, crude fiber, ash, and crude fat in grain raw materials. It is found that as the grain size decreased, the content of carbohydrates and fat, as well as the activity of amylase, increased significantly. A positive correlation between the size of grain particles and the content of phenolic acids and protein in them is shown. It is known that dry fractionation of barley and oat grains gives a product enriched with valuable substances, containing dietary fiber, β-glucans and tokols. The grain size can affect the efficiency of the fiber fermentation process as well as the availability of bound polyphenols that act as antioxidants. It is found that with a decrease in the size of bran particles, there is a redistribution of dietary fiber components from insoluble to soluble fractions, a significant increase in phenolic acids, flavonoids, anthocyanins and carotenoids extracted from them, as well as an increase in antioxidant activity. At the same time, a decrease in the particle size of dietary fiber can negatively affect the bioavailability of thiamine, riboflavin and pyridoxine. The research demonstrates that the use of fractionation of wheat bran and the inclusion of only some parts of the bran in food products can significantly increase the functional potential of the latter.