Abstract:
In this study, oxidized deacetylated konjac glucomannans with different degrees of oxidation were prepared by a combination of deacetylation and ozone oxidation. Carboxyl groups were found to be introduced into the modified konjac glucomannan while acetyl groups were removed. The backbone, branched chains, and crystal structure of modified konjac glucomannan were not significantly affected. The whiteness was enhanced to 97-99 % and the thermal degradation temperature was up to 250 °C after modification. The solubility of the modified konjac glucomannan (oxidized for 60 min) was significantly increased to 84.56 % (p < 0.05), while its viscosity and swelling power were notably decreased owing to the changes in molecular weight (from 106 to 104) and functional groups. Rheological analysis showed that oxidized deacetylated konjac glucomannan has the ability to form soft-textured gels and the potential to develop dysphagia foods. Future studies should focus on the gelation mechanisms of oxidized deacetylated konjac glucomannan.
摘要:
在这项研究中,通过脱乙酰和臭氧氧化的组合制备了具有不同氧化程度的氧化脱乙酰魔芋葡甘露聚糖。发现羧基被引入到改性的魔芋葡甘露聚糖中,而乙酰基被去除。骨干,支链,改性魔芋葡甘聚糖的晶体结构没有显著影响。改性后,白度提高到97-99%,热降解温度高达250°C。改性魔芋葡甘露聚糖(氧化60分钟)的溶解度显著提高到84.56%(p<0.05),而由于分子量(从106到104)和官能团的变化,其粘度和溶胀能力显着降低。流变学分析表明,氧化的脱乙酰魔芋葡甘露聚糖具有形成柔软质地的凝胶的能力,并具有开发吞咽困难食品的潜力。未来的研究应集中在氧化脱乙酰魔芋葡甘聚糖的凝胶化机理上。