Browsing by Author "Vashkevich, Olena Yu."

Now showing 1 - 1 of 1

Searching for the Chemical Component of the Starch Dehydration Process
(Ukrainian State University of Science and Technologies, 2026) Nikolenko, Mykola V.; Sakhno, Yu.; Myrhorodska-Terentieva, V. D.; Hrechka, Dmytro S.; Vashkevich, Olena Yu.
ENG: As is well known, the first stage of starch heat treatment is the dehydration process, which proceeds in a kinetic mode with a relatively high activation energy value of 40–60 kJ/mol. The reason for this may be both the energy-consuming process of hydrogen bond destruction in starch and the chemical reaction between the OH groups of polycarbohydrates with the formation of ester bonds. The aim of the study was to find evidence of the formation of such bonds during the heat treatment of corn starch. The studies were performed by FTIR spectroscopy in the temperature range of 60–2550C at a heating rate of 40C/min. It was found that the number of OH groups of polycarbohydrates gradually decreases during starch heating, while the water content and ether-bond signals, on the contrary, increase. An increase in water concentration was observed when starch was heated to a temperature of 1300C. It was concluded that these trends are well explained by the course of the condensation reaction between the OH groups of amylose and amylopectin molecules. For the first time, it was found that during prolonged drying of starch in a vacuum, even at a temperature of 500C, the crosslinking of polycarbohydrate molecules occurs due to the formation of ester bonds. It is noteworthy that such crosslinking occurs without the use of chemical reagents, but only by shifting the equilibrium of the condensation reaction as a result of the continuous removal of water from starch.