Effect of Dehulling and Hydrothermal Treatment on the Amino Acid Content of Soriz (<i>Sorghum oryzoidum</i>)

Abstract

Cereals are the basic element in ensuring the food security of the population through the significant intake of carbohydrates, proteins, dietary fiber, vitamins and minerals. The processing of cereals leads to changes in their nutritional quality, which could lead to both reduced nutrients and anti-nutrients. Gluten-free cereal varieties attract attention as raw materials to improve the nutritional quality of food and to diversify the product range. Sorghum ( Sorghum oryzoidum ) is a hybrid of sorghum, obtained at the Institute for Scientific Research for Corn and Sorghum in the Republic of Moldova, by crossing Sudan grass ( S . sudanense ) and bicolor sorghum ( S . bicolor ). The research aimed to determine the impact of dehulling and hydrothermal treatment on the amino acid content of soriz. The obtained results reported that the dehulling and hydrothermal treatment led to the uneven modification of the amino acid content in the investigated samples. As a result of dehulling, the total amount of essential amino acids decreased by 19.8% compared to the native grain. Boiling whole grains without prior hydration led to 34% loss of essential amino acids compared to native grains, and pre-hydration of the grains and subsequent boiling reduced essential amino acid losses by 8% compared to cooked grains without hydration. Boiling grains with pre-hydration had a positive effect on the chemical index of lysine, methionine and cysteine, leucine and tryptophan. However, the nutritional quality of sorghum grain proteins and derivatives obtained, evaluated according to the chemical index, is low. The results obtained reported that dehulling and hydrothermal treatment unevenly altered the amino acid content, and the method of boiling grains with pre-hydration had a positive effect on the CSI of lysine, methionine and cysteine, leucine and tryptophan.