强化发酵对小米淀粉分子结构及老化特性的影响

Effect of enhanced fermentation on molecular structure and aging characteristics of millet starch

利用自然发酵液中对淀粉老化特性起主要作用的菌种(乳酸菌:戊糖片球菌、植物乳杆菌、屎肠球菌,酵母菌:酿酒酵母,芽孢菌)强化发酵,研究强化发酵对小米淀粉分子结构及老化特性的影响,为剖析自然发酵对淀粉老化特性的改性机理提供理论基础及数据支持,为开发发酵小米新途径、生产小米发酵剂提供依据。采用0.2 g/100 m L的Na OH提取发酵后的小米淀粉,研究强化发酵对小米淀粉颗粒特性、红外光谱、分子量及老化特性的影响。结果如下:发酵并未改变淀粉的偏光十字;自然发酵后小米淀粉表面被侵蚀,强化发酵后淀粉颗粒表面侵蚀迹象变重,孔道加深且数量增多;自然发酵后小米淀粉官能团区的峰位未变,强化发酵小米淀粉指纹区图谱部分消失,且自然发酵及强化发酵小米淀粉的特征峰强度减弱;强化发酵后I区的重均、数均分子量升高,而自然发酵重均、数均分子量略有降低,但II区二者的重均、数均分子量均降低;自然发酵及强化发酵后淀粉的回生值及最终黏度降低。发酵使淀粉的分子结构发生改变,短期抗老化性能提高。

Study on the molecular structure and the influence of aging characteristics of enhanced fermentation millet starch by the strain （ Lactobacillus plantarum, Pediococcus pentosaceus, Enterococcus faecium, Saccharomyces cerevisiae and Bacillus） which play an important role in natural fermentation of starch aging characteristics, for analysis of natural fermentation and provide a theoretical basis and data support on the modification mechanism on the aging properties of starch, provide the basis for the new ways of millet developing, the fermentation production of millet fermentation agent. Picking up the starch from fermented millet by 0.2 g/100 mL NaOH, researched the particle characteristics, effects of functional groups and molecular weight, and aging properties with different kinds of strains to enhanced fermentation. Results were as follows .. Fermentation did not changed the polarization cross of starch - The surface of millet starch had been eroded which was fermented nature fermentation, but the starch granule surface which fermented by enhanced fermentation had been eroded seriously, deeper and increasing the number of channels - The fermentation by nature fermentation did not changed the functional area of the peaks of millet starch, and the fingerprint region of millet starch fermented by enhanced fermentation were disappeared, but both of them the intensity of characteristic peak was lower - The weight average and number average weight molecular of I were decreased after the fermentation of nature fermentation, while the enhanced fermentation had increased. But in the II, the weight average and number average weight molecular of nature fermentation and enhanced fermentation were decreased. The retrogradation value of starch which fermented by nature fermentation and enhanced fermentation was decreased. Fermentation had changed the molecular structure of starch, and the short term anti aging performance was improved.