关键词: 半干磨, 小米, 损伤淀粉, 粒径分布, 面条

Abstract: In order to diversify the consumption of millet in the traditional diet, the effect of semidry milling on the quality attributes of millet flour and millet noodles was investigated. The physical and functional properties of millet flour were determined by means of damaged starch analyzer, laser particle size analyzer, X-ray diffractometer, scanning electron microscope and Mixolab. The quality characteristics of millet noodles were determined by low field nuclear magnetic resonance, cooking test, texture analyzer and sensory evaluation. The results indicated that semidry milling of millet at 22% and 26% moisture contents yielded flour with lower percentage of damaged starch and smaller average particle size as compared to dry-milled millet flour (P < 0.05), and consequently semidry-milled millet flour exhibited higher crystallinity degree and superior integrity of starch granules. Moreover, semidry-milled millet flour induced higher water absorption and longer stability time of dough (P < 0.05). Upon gelatinization, the water absorption index and swelling power of semidry-milled millet flour at 26% moisture content were greater than those of dry-milled millet flour during thermal treatment (P > 0.05), showing increased peak viscosity and greater resistance to retrogradation in the Mixolab curves (P < 0.05). Besides, incorporation of semidry-milled millet flour enhanced binding between moisture and other components in millet noodles, leading to an significant increase in the springiness and cohesiveness and a significant reduction in the adhesiveness and cooking loss of millet noodles (P < 0.05). Partial least squares regression analysis indicated that the level of damaged starch granules produced by different milling techniques could have a greater effect on the quality attributes of millet flour and millet noodles as compared to the average size of the starch granules. Due to the lowest degree of starch damage, semidry milling of millet at 26% moisture content can yield high-quality millet flour and millet noodles, which demonstrates a feasible milling method for industrial deep processing of millet.

Key words: semidry milling, foxtail millet, damaged starch, particle size distribution, noodles