Physicochemical properties, characteristics, and consumer acceptance of whole grain sorghum expanded extrudates

Abstract

The objective of this work was to study how six sorghum genotypes affected the production of whole grain expanded snacks using extrusion cooking and to evaluate their physicochemical properties, sensory characteristics, and consumer acceptance. The chemical composition and antioxidant capacity of raw flours from whole grains were evaluated. Sectional expansion index, paste viscosity, and texture (hardness and crispness) analyses as well as acceptance tests and check-all-that-apply questions were conducted on the extrudates. White pericarp sorghum extrudates presented the highest sectional expansion and sensory acceptance, and were negatively correlated to total phenolic compounds and antioxidant capacity. Sorghums with tannins had the highest antioxidant capacity but the lowest values of sensory acceptance. The combination of different sorghum genotypes could be used to produce a final product with good antioxidant capacity and acceptability. Practical applications Sorghum is the fifth most produced cereals in the world largely used for animal feed but limited in direct human consumption. It is known that it has interesting agricultural characteristics such as drought and heat resistant and also contain expressive content of bioactives linked with health benefits. As an example, tannin sorghum has the greatest values of antioxidant activity when compared with other cereals, but it was demonstrated by our work that it has low sensory acceptance; on the other hand, nontannin sorghum showed higher acceptability. By understanding the technological aspects and sensory differences of sorghum genotypes processed by extrusion cooking allow the development of sorghum ready-to-eat blend products (tannin and nontannin sorghum) with the best of both antioxidant capacity and sensory acceptance. Our results could be used by the food industry to develop novel products with improved technological and sensory characteristics that could be introduced as functional healthy food options with the advantage of being a gluten-free product.