夏谷区主栽谷子品种淀粉理化特性研究

从夏谷区主栽品种中选取9个谷子品种作为供试材料，对其淀粉的颗粒形态及大小、化学组成、碘蓝值、透光率、冻融稳定性、糊化特性、溶解度与膨胀势及凝沉特性等理化性质进行系统研究。结果表明：小米淀粉颗粒均为单粒，由0.48～2.25μm与3.50～29.32μm两种不同粒径范围的颗粒组成，多呈多角形，少数呈卵圆形，具有清晰可见的偏光十字，品种间淀粉颗粒形态差异明显。直链淀粉含量为2.91%～15.80%，碘蓝值为0.601～0.809，透光率为4.4%～22.3%，析水率为0.77%～62.23%，品种间差异显著。不同品种小米淀粉的糊化特性、溶解度与膨胀势及淀粉糊的凝沉特性也有着明显的差异。因此，可根据不同的加工目的选择不同的谷子品种。

Physical and Chemical Properties of Starch from Major Summer Millet Cultivars in China

In order to offer theoretical references for the application of millet starch and the screening of cultivars with good processing suitability, 9 major summer millet cultivars in China were selected to systematically study the granule morphology and size, chemical composition, iodine blue value, light transmittance, freeze-thaw stability, pasting properties, solubility and swelling power, retrogradation properties and other physicochemical properties of starches from these cultivars. The results showed that starch granules from each millet cultivar were single granules with a particle size in the range of 0.48-2.25μm and 3.50-29.32 μm. Starch granules were mostly polygonal though sometimes oval in shape, and displayed clear polarization cross. The different millet cultivars showed an obvious difference in the morphology of starch. The amylose content, iodine blue value, light transmittance, and syneresis rate of the tested millet cultivars were in the range of 2.91%-15.80%, 0.601-0.809, 4.4%-22.3% and 0.77%-62.23%, respectively, with significant differences among these millet cultivars. Moreover, significant differences in starch pasting properties, solubility and swelling power and retrogradation properties were also observed. Therefore, different millet cultivars are specifically suitable for different processing purposes.