Department of Food Science and Technology, Chaudhary Devi Lal University, Sirsa, India.
Department of Food Science and Technology, Chaudhary Devi Lal University, Sirsa, India; Department of Food Science and Technology, Maharaja Ranjit Singh Punjab Technical University, Bathinda, India.
Int J Biol Macromol. 2019 Jun 15;131:1077-1083. doi: 10.1016/j.ijbiomac.2019.03.179. Epub 2019 Mar 26.
Pearl millet (PM) starch was reacted with acetic anhydride at different concentrations (1.25, 2.5, 3.75 & 5.0%) and its physicochemical, rheological, morphological and in vitro digestibility properties were compared with native starch. The acetyl (%) and degree of substitution (DS) of acetylated starches ranged between 1.07 and 2.15% and 0.040-0.081, respectively. Swelling power and solubility of acetylated PM starch increased progressively upto 3.75% level of acetylation, however, further increase in acetylation levels resulted in a decrease. Peak, setback and final viscosities of acetylated PM starches were higher than their native counterpart starch. Both native and acetylated PM starches showed similar A-type X-ray diffraction patterns. During heating, storage modulus (G') and loss modulus (G″) of acetylated starches ranged between 753 and 1177Pa and 96-129Pa, respectively. G' was much higher than G'' at all the values of angular frequency studied. Both native and acetylated PM starch pastes showed flow behaviour index value of <1. For acetylated starches, both, yield stress and consistency index values were higher than native starch. Readily digestible and slowly digestible starch contents of acetylated PM starches varied between 44.3 and 45.5% and 27.3-32.5%, respectively, the highest values observed for starch acetylated at 3.75% and 1.25% acetic anhydride concentrations.
珍珠粟（PM）淀粉与不同浓度的乙酸酐（1.25、2.5、3.75 和 5.0%）进行反应，将其理化性质、流变学性质、形态学性质和体外消化率与原淀粉进行比较。乙酰化淀粉的乙酰基（%）和取代度（DS）分别在 1.07-2.15%和 0.040-0.081 之间。乙酰化 PM 淀粉的膨胀力和溶解度在 3.75%的乙酰化水平下逐渐增加，但进一步增加乙酰化水平会导致其下降。乙酰化 PM 淀粉的峰值、回值和最终黏度均高于原淀粉。原淀粉和乙酰化 PM 淀粉均表现出类似的 A 型 X 射线衍射图谱。在加热过程中，乙酰化淀粉的储能模量（G'）和损耗模量（G″）范围在 753-1177Pa 和 96-129Pa 之间。在所研究的所有角速度值下，G'均远高于 G″。原淀粉和乙酰化 PM 淀粉糊均表现出小于 1 的流动行为指数值。对于乙酰化淀粉，屈服应力和稠度指数值均高于原淀粉。乙酰化 PM 淀粉的快速消化淀粉和慢速消化淀粉含量分别在 44.3-45.5%和 27.3-32.5%之间，在 3.75%和 1.25%乙酸酐浓度下观察到最高值。
