在不同温度下生产和表征再结晶的线性α-glucans,以控制可控的热稳定性和可消化性
Ren Wang1, Xiaoli Wu1, Cuiping Yi2
1Key Laboratory of Carbohydrate Chemistry and Biotechnology, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, and School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, People's Republic of China.
Food chemistry
|March 31, 2024
概括
研究了线性α-葡萄糖 (LAG) 的再结晶行为. 较长的LAG链和A型晶体增强了热稳定性,降低了消化能力,产生了耐性粉.
科学领域:
- 食品科学 食品科学 食品科学
- 碳水化合物化学 碳水化合物化学
- 生物化学 生物化学
背景情况:
- 线性α-葡萄糖 (LAG) 的分子结构及其结晶温度显著影响再结晶的LAG的热稳定性和消化性.
- 然而,对LAG在温度变化时的精确再结晶行为仍然不完全理解.
研究的目的:
- 为了研究线性α-glucans (LAGs) 的再结晶行为,其链长度因温度而变化.
- 阐明LAG链长度,晶体结构 (A型与B型) 以及由此产生的热稳定性和体外消化性之间的关系.
主要方法:
- 线性α-葡萄糖 (LAG) 是通过链延长和脱枝技术从氨酸合成的.
- 在不同的温度 (4°C和50°C) 进行了再结晶实验,以诱导不同的晶体结构.
- 使用差分扫描热度计 (DSC) 来评估再结晶的LAG的热稳定性.
主要成果:
- 在4°C的再结晶产生了B型结晶结构,相对结晶度在23.7%至46.1%之间.
- 在50°C的缓慢再结晶,特别是链条长度为40.2,产生了A型晶体异形.
- 与B型晶体相比,A型晶体表现出更高的热稳定性.
- 增加LAG链条长度增强了双螺旋尺寸,从而改善了粉晶石组装.
- 这种组合增强了热稳定性和减少了体外消化能力,产生高达75.4%的耐性粉 (RS).
结论:
- 该研究阐明了LAG的再结晶行为,证明了A型和B型晶体结构的温度依赖的形成.
- 在确定有序的双螺旋结构的形成方面,LAG链条的长度是一个关键因素,它会影响热稳定性.
- 优化的再结晶条件产生了具有增强热稳定性和显著降低消化能力的LAG,为抗性粉生产提供了潜力.
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