Gluten free Maize Cookies Prepared with High-amylose Starch: In Vitro Starch Digestibility and Sensory Characteristics

In an effort to improve gluten-free (GF) cookies overall nutritional aspects, as a means of decreasing the glycemic index and increasing the resistant starch content, experimental GF maize cookies were formulated with a normal amylose GF maize flour mix (NAM) and increasing levels of high amylose maize starch flour (HAM) represented by substitution ratio of 0%, 25% and 50% on a total flour (NAM+HAM) basis. Chemical composition, in vitro starch digestibility and sensory evaluation were carried out. Dietary fibre, total starch and amylose contents increased (p<0.05) when the level of HAM increased in the recipe for GF cookies. Both resistant starch and slowly digestible starch increased (p<0.05), whereas rapidly digestible starch and available starch levels decreased (p<0.05) when the level of HAM increased in the formulation. Slower rate of starch hydrolysis (up to minus 66.0%; p<0.05) and lower predicted glycemic index (up to minus 35.0%; p<0.05) were recorded when HAM increased in the composite. No differences were reported in the sensory profile and in the overall acceptability of GF maize cookies formulated with increasing levels of HAM. Taking together, present in vitro findings suggest that the partial substitution of NAM with HAM contributed to formulate GF maize cookies with slowly digestible starch properties without affecting overall sensory attributes.