Sorochynska Y. Improving the technology of gluten-free bread using sorghum flour

The aim of this thesis is to improve the technology of gluten-free bread production. Such improvement was attempted by using the domestic selection of sorghum flour (the "Ponki" variety) enriched with whey, casein, meal from pumpkin seed kernels as well as calcium and magnesium citrates. Guar gum and hydroxypropylmethylcellulose were used in the gluten-free dough as structuring agents. Chemical composition and technological properties of sorghum flour grown domestically in Ukraine have been proven as suitable for gluten free bread production. Trial baking was performed with the use of starch-sorghum mixture of 60% corn starch, 10% potato, 30% sorghum flour. Research has proven the expediency of using a mixture of guar gum and HPMC as a structurant of the dough with the 60:40 ratio of starch-sorghum mixture. The steamless dough mixing method without fermentation was proven to be the most efficient. It included adding 10% of sour whey relative to the total weight of the starch-sorghum mixture. As gluten-free products from starches contain only about 1% protein and their starch-sorghum counterparts contain 2.4%, it is advised to include 5-7% of mycelial casein relative to the total weight of the starch-sorghum mixture in the formulation. The results of test baking demonstrate the benefits of using meal from pumpkin seed kernels (SHNG) for the purpose of enriching products from starch-sorghum mixture with protein, dietary fiber and other physiologically active substances. Tests also ascertain that calcium and magnesium citrates are possible and desirable additives to the mixture. Recipes for three new gluten-free bakery products were established based on the findings of this study. They were approved by the Ukrainian association of the baking industry enterprises "Ukrkhlibprom" and registered with titles "Starch-sorghum bread with whey", "Starch-sorghum bread with pumpkin", "Starch-sorghum bread with milk". These newly developed products have improved shelf life due to the high water absorption capacity of the formulation components, as suggested by the elevated content of tightly bound moisture. Bisulfite binders were detected in the crust and crumb, manifesting in the appealing aroma of the bread. The rate of carbohydrate digestion is not expected to be significantly affected despite the product enrichment with sorghum flour, whey, casein, LPG and citrates of calcium and magnesium. Experimentally developed products demonstrate improved chemical composition compared to starch products, in particular in terms of content of protein, dietary fiber, minerals and vitamins.