[关键词]
[摘要]
从谷子主产区山西省选取8个具有代表性的谷子栽培品种作为供试材料,分析研究了其淀粉的颗粒形态及粒径大小、直链淀粉含量、碘蓝值与淀粉糊的透光率、冻融稳定性、糊化特性、溶解度与膨胀度及凝沉特性等理化性状。结果表明:小米淀粉颗粒均为单粒,外形规整,多数为多角形,少数为卵圆形,具有清晰可见的偏光十字,不同品种间淀粉颗粒形态差异明显。小米淀粉小颗粒的粒径为0.42~2.25 μm,大颗粒的粒径为3.42~29.26 μm,小米淀粉的粒径分布特征呈现出“三峰”型。8个品种的直链淀粉含量变幅为2.22~17.96%,碘蓝值变幅为0.586~0.872,透光率变幅为2.4~29.2%,析水率变幅为3.67~49.85%,糊化温度变幅为67.6~78.8 ℃,各品种间具有显著差异。此外,各品种淀粉的糊化特性、溶解度、膨胀势及淀粉糊的凝沉特性也有着明显的差异。因此,应根据不同的加工目的采用相适宜的品种。
[Key word]
[Abstract]
To further understand the physical and chemical properties of the millet starches in Shanxi province, eight typical species of millet were chosen and the particle morphology, size, amylose content, iodine blue value, light transmittance, freeze-thaw stability, gelatinization characteristics, solubility, swelling power, retrogradation curve and other physicochemical characterizations were evaluated. Results showed that the millet starch granules were all single particle with regular shape, and most of the millet starch particles were polygonal while few were ovoid. All the particles had clear polarizing cross, and the morphological differences of starch grain particles were evident between varieties. Moreover, on the basis of particle size, the eight millet cultivars were clearly classified as two categories which ranged from 0.42 to 2.25 μm and 3.42 to 29.26 μm, respectively. The amylose content, iodine blue value, light transmittance, water segregation rate, and gelatinization temperature were in the range of 2.22~17.96%, 0.586~0.872, 2.4~29.2%, 3.67~49.85% and 67.6~78.8 ℃, respectively, indicating that the differences between different varieties were significant. All of these results suggested that the different millet varieties should be chosen according to the different processing purposes.
[中图分类号]
[基金项目]
国家现代农业产业技术体系建设专项资金资助(nycytx-13)