Effect of dry-heat treatment on acrylamide and HMF formation in maize flour

Thermal treatments have numerous applications as valuable tools for extending the shelf-life of flour by inactivating enzymes and reducing moisture content [1]. Besides the biological effects, the dry-heat process has a significant impact on the techno-functional, nutritional properties as well as bioactive compounds of flour [2]. However, during different thermal treatments, many potentially harmful compounds could be formed through the Maillard reaction. Recently, two heat-induced contaminants have gained much interest: acrylamide and HMF [3]. HMF forms as a result of the dehydration of hexose sugars or the Maillard reaction during heating [4], while acrylamide in foods is formed via the Maillard reaction from free asparagine in the presence of carbonyl compounds such as reducing sugars during thermal processes. The present study aimed to evaluate the effects of the thermal treatment at different temperatures: 100, 125, 135, 150, and 165°C, on the HMF and acrylamide formulation, as well as the antioxidant capacity of maize flours. The experimental material consisted of three maize hybrids with different colours and kernel types (white-standard, yellow and blue-popping). Maize samples were ground on a lab mill to a fine powder (