Exploring the nutritional and techno-functional benefits of purple hull-less barley in extruded ready-to-eat cereals

Abstract

This study explores the potential of purple hull-less barley for producing ready-to-eat cereals, focusing on the impact of extrusion on their nutritional and techno-functional properties. Four formulations were assessed: 100% whole barley, 100% pearled barley, 15% barley bran-85% refined wheat flour, and 100% refined wheat. Higher temperatures and screw speeds, along with lower moisture levels, significantly influenced expansion, density, and hardness. Whole barley extrudates were high in β-glucans (7.4%) and arabinoxylans (6.8%), which negatively correlated with expansion (r = −0.857 and r = −0.796) and positively with hardness (r = 0.833 and r = 0.738) and density (r = 0.673 and r = 0.863). Pearled barley extrudates showed improved textural properties compared to whole barley, with reduced hardness and density. The phenolic profile and antioxidant capacity of raw materials and extrudates were compared, revealing a significant decrease after extrusion across all formulations. Incorporating barley bran into refined wheat flour tripled the antioxidant capacity of the refined wheat extrudates. Both whole and pearled barley extrudates offered a low estimated glycemic index, suitable for low-GI diets. Overall, purple hull-less barley presents a nutritious option for extrusion, with pearling and bran utilization improving both the techno-functional and nutritional qualities for health-conscious consumers.