Characterizing the functional and practical performance of hydrolyzed lactose syrup in selected foods

Abstract

Greek yogurt acid whey (GAW), a byproduct of Greek yogurt production, is both an expensive waste product and an environmental concern. Previous work has developed a system to convert GAW into sustainable usable products, specifically milk minerals and glucose-galactose syrup (GGS). However, research regarding the applications of GGS is limited. This work aims to fully characterize the physical and functional properties of GGS and characterize the functionality of the syrup in several diverse food applications. The physical and functional properties of GGS, boiling point elevation, freezing point depression, browning, and rheological behavior, were characterized. Compared to solutions of sucrose and corn syrup, GGS decreased the freezing point and increased the boiling point of water further. At the same solids content, GGS had a lower viscosity than solutions of sucrose and 43 DE corn syrup at freezing and room temperatures. GGS behaved more similarly to corn syrup than to sucrose when undergoing browning reactions. The ability of GGS to act as a partial replacement, at 40% and 80% molarity, for sucrose in high-ratio cake and as a partial replacement for corn syrup and sucrose in gummies and caramel was determined. In caramels, GGS significantly altered product characteristics: increased browning reactions, decreased hardness and increased stickiness across all formulations. Due to these significant changes, GGS was found to be unsuitable as a direct replacement for corn syrup or sucrose. However, the addition of GGS may be useful for manipulating caramel properties. Gelatin gummies made with 40% and 80% molar replacement of sucrose and corn syrup by GGS showed several significant differences from control formulations. The texture profile of the gummies was highly consistent across all formulations; however, increasing levels of GGS increased the rate of crystallization. GGS was found to be an unrealistic replacement for corn syrup at 40 and 80% and sucrose at 80% due to the increase in the onset of crystallization, creating an undesirable product. In high ratio cake, GGS increased foamability and yield stress in the batter and significantly affected the baked cake formulations. A significant increase in color occurred in both 40% and 80% molar replacement of sucrose, causing GGS to be an unviable replacement in cake due to production of off flavors and undesirable appearance. In summary, the functional and physical properties of GGS were measured and compared to those of corn syrup and sucrose. GGS was evaluated in various food applications, demonstrating viability as a partial sucrose replacement in gelatin gummies but proving unsuitable for high-ratio cakes. The effectiveness of GGS in caramels depends on the desired final characteristics of the product.