Hydrolysis of chlorogenic acid in sunflower flour increases consumer acceptability of sunflower flour cookies by improving cookie color

Abstract

Sunflower meal, a byproduct of sunflower oil pressing, is not commonly used in alkaline baking applications. This is because chlorogenic acid, the main phenolic antioxidant in sunflower seeds, reacts with protein, giving the baked product a green discoloration. Our group previously demonstrated that a chlorogenic acid esterase from Lactobacillus helveticus hydrolyzes chlorogenic acid in sunflower dough cookie formulations, resulting in cookies that were brown instead of green. This study presents a sensory analysis to determine the acceptability of enzymatically upcycled sunflower meal as an alternative protein source for those allergic to meals from legumes or tree nuts. We hypothesized that the mechanism of esterase‐catalyzed chlorogenic acid breakdown does not influence the cookies’ sensory properties other than color and that consumers would prefer treated, brown cookies over non‐treated cookies. Cookies made from sunflower meal were presented under green lights to mask color and tested by 153 panelists. As expected, the sensory properties (flavor, smell, texture, and overall acceptability) of the treated and non‐treated cookies were not statistically different. These results corroborate proximate analysis, which demonstrated that there was no difference between enzymatically treated and non‐treated cookies other than color and chlorogenic acid content. After the cookie color was revealed, panelists strongly preferred the treated cookies with 58% indicating that they “probably” or “definitely” would purchase the brown cookies, whereas only 5.9% would buy green, non‐treated cookies. These data suggest that esterase‐catalyzed breakdown of chlorogenic acid represents an effective strategy to upcycle sunflower meal for baking applications. Practical Application Sunflower meal is currently used as animal fodder or discarded. A major factor preventing sunflower meal use is its high chlorogenic acid content, which causes a green discoloration of baked goods made from sunflower meals under alkaline conditions. This study presents a sensory analysis in which panelists evaluate cookies made with sunflower flour that was treated with an esterase that breaks down chlorogenic acid. The results show that enzymatic treatment prevents greening and that panelists strongly prefer esterase‐treated, non‐green cookies, thus demonstrating the feasibility of utilizing sunflower flour in baking applications.