Effect of combined UV-thermosonication and Ecklonia cava extract on advanced glycation end-products in soymilk

Thermal treatment is used to inactivate microbes in soymilk, but it increases the amount of advanced glycation end products (AGEs). Therefore, this study examined if ultraviolet light with thermo-sonication (UVTS) and Ecklonia cava extract (EX) could provide an alternative process to prevent AGEs formation in processed soymilk. A coiled tube UV reactor was used simultaneously with an ultrasonic generator for UVTS treatment, while an autoclave was employed for thermal treatment. UVTS treatment was examined at different temperatures and flow rates to achieve a 5-log reduction of pre-inoculated Escherichia coli and Salmonella typhimurium in soymilk. After confirming EX's anti-glycation effects against fructosamine, ɑ-dicarbonyl compounds, protein carbonyl content, and AGEs formation, it was added to soymilk before the UVTS. The ɑ-dicarbonyl compounds (glyoxal and methylglyoxal) and AGEs (N^ε-(1-carboxymethyl)-l-lysine [CML] and N^ε-(1-carboxyethyl)-l-lysine [CEL]) in soymilk increased after autoclaving (AC). Compared with AC, the UVTS with.05% EX decreased glyoxal, methylglyoxal, CML, and CEL by 78%, 82%, 32%, and 59%, respectively. These results indicated that UVTS with EX could be an alternative pasteurization process for soymilk that minimizes AGEs formation.