Effects of milling condition on nutritional, physicochemical, and textural properties of highland barley grains

Background and ObjectivesA lower degree milling to obtain cereal grains with acceptable cooking qualities was recommended for the higher retainment of bioactive compounds. The aim of this work was to investigate effects of milling condition on nutritional, physicochemical and cooking qualities of highland barley (HB) grains. FindingsEffects of tempering results showed that increased water addition amount caused decrease in degree of milling (DOM) and increase in head rice yield (HRY). Effects of milling condition results showed that activities of polyphenol oxidase (PPO) and peroxidase (POD) showed significantly decreasing tendency as DOM increased. When DOM increased from 0% to 8%, the POD activity decreased from 140 to 3.75 Ug(-1) min(-1), with inactivation rate of 97.3%. Milling also witnessed a 70.1% reduction of PPO activity, from 27.74 to 8.30 Ug(-1) min(-1). Pasting results showed that viscosity parameters gradually increased and pasting temperature decreased as DOM increased. Texture results showed that the hardness, gumminess and chewiness of HB grains gradually decreased with the increase of DOM, while there was no significant difference in resilience, adhesiveness and springiness. ConclusionsBased on the nutritional, physicochemical and cooking qualities of HB grains, the optimal milling condition of HB grains was fixed at 6% of tempering water, 10 min of tempering time and 10% of DOM.