Department of Analysis and Evaluation of Food Quality, University of Agriculture, Balicka 122, 30-149 Krakow, Poland.
Department of Analysis and Evaluation of Food Quality, University of Agriculture, Balicka 122, 30-149 Krakow, Poland.
Int J Biol Macromol. 2018 Jan;106:57-67. doi: 10.1016/j.ijbiomac.2017.07.177. Epub 2017 Aug 10.
This study was aimed at determining the effect of the amylose content of starch and oxidation level of potato starch on the structure of starch granules, and susceptibility to chemical modification (acetylation) and subsequent generation of radicals. Potato starch and waxy potato starch were oxidised with sodium hypochlorite applied in doses corresponding to 10, 20, and 30gCl/kg starch, and then acetylated with acetic acid anhydride. The carboxyl, carbonyl, acetyl groups were determined in modified starches. Structural properties of starch granules were evaluated based on gelatinisation, crystallinity, specific surface, intrinsic viscosity, and microphotographs by SEM microscope. The electron paramagnetic resonance (EPR) measurements were carried out to establish starch susceptibility to radical creation upon chemical modification and UV radiation. The amount of formed radicals was treated as a measure of the starch structure stability. The higher amount of amylose and the highest level of oxidation led to strong starch structure destruction and consequently facilitated radical generation. Study results showed also that amylose content as well as the degree of starch oxidation modified consecutive acetylation process. The different effectiveness of the acetylation processes influenced the morphology and structure of starch granules.
本研究旨在确定淀粉直链淀粉含量和马铃薯淀粉氧化程度对淀粉颗粒结构以及对化学修饰（乙酰化）的敏感性和随后自由基生成的影响。用次氯酸钠将马铃薯淀粉和蜡质马铃薯淀粉氧化，施加的剂量分别对应于 10、20 和 30gCl/kg 淀粉，然后用乙酸酐乙酰化。在改性淀粉中测定了羧基、羰基、乙酰基的含量。基于糊化、结晶度、比表面积、特性粘度和 SEM 显微镜的微观照片评估淀粉颗粒的结构特性。通过电子顺磁共振（EPR）测量研究了化学修饰和 UV 辐射下淀粉生成自由基的敏感性。形成的自由基的量被视为淀粉结构稳定性的度量。直链淀粉含量和氧化程度越高，淀粉结构破坏越严重，自由基生成越容易。研究结果还表明，直链淀粉含量和淀粉氧化程度会改变连续乙酰化过程。乙酰化过程的不同效果会影响淀粉颗粒的形态和结构。
