In the master’s thesis, we examined the influence of various factors on the reactions between reducing sugars and free amino acids during thermal treatment of the samples. We focused on the effects of adding selected acids and antioxidants, as well as the role of different reducing sugars and free amino acids. We also studied the influence of the presence of phenyl and thiol groups and the molar ratio between the amino acid and the sugar. In the experimental part, three analytical methods were applied: thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and FTIR spectroscopy, with which we monitored changes in mass during heating from 25 to 550 °C, heat flow at 110 °C, and IR absorbance at different heating times in a drying oven at 110 °C. The results showed that the onset and extent of the reactions depend on the glucose:asparagine molar ratio. Reactions between aldoses and asparagine proceed to a greater extent and start after a shorter period of thermal treatment compared to reactions between ketoses and asparagine. A comparison of cysteine and phenylalanine with alanine indicated that the presence of thiol and phenyl groups also affects the reactions. The addition of acids to the glucose–asparagine sample under low water activity conditions influences the course of the reactions. We also found that antioxidants, such as ascorbic acid (vitamin C) and Trolox (a water-soluble vitamin E analog), similarly affect the progression of reactions during thermal treatment.
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