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Updated: May 9, 2025

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Analysis and Specification of Starch Granule Size Distributions
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粉分子量和链长分布对0-3纹理水平的影响
Xiaodong Tian1, Junrong Huang1, Hongliang Li1
1School of Food Science and Engineering, Natural Food Macromolecule Research Center, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021, China.
概括
使用α-氨基酶的米粉的酶性水解降低了其分子量,改变了链条长度的分布. 这个过程有效地降低了纹理水平从固体 (第7级) 到液体 (第3级) 根据国际缺食饮食标准化倡议的指导方针.
科学领域:
- 食品科学 食品科学 食品科学
- 生物化学 生物化学
- 材料科学 是一种材料科学.
背景情况:
- 国际消化不良饮食标准化倡议 (IDDSI) 将纹理分类,其中3至0级代表液体.
- 粉分子特性对IDDSI 3-0级纹理的影响尚不清楚.
- 了解这些关系对于开发适合失调的食物至关重要.
研究的目的:
- 为了研究酶化水解对大米粉的影响.
- 为了将粉分子量和链长度的变化与IDDSI纹理水平相关联.
- 建立创建基于粉的液体食品的理论基础.
主要方法:
- 米粉 (IDDSI 7级) 通过使用α-amylase进行了酶性化.
- 分析了平均分子量 (Mw),分子量分布 (Mw/Mn) 和链长分布 (Dp) 的变化.
- 测量了粉分子链的高度和粗度.
- 评估了烯和氨酸的水解程度.
主要成果:
- 酶性水解使米粉的平均分子量从9.48 × 10^7 g/mol降低到1.17 × 10^4 g/mol.
- Mw/Mn从22.0下降到3.3,表明向更短的链转移.
- 短链 (Dp 6-12) 的比例从41.1%增加到70.5%.
- 粉分子链高度从1.1nm降至0.7nm,粗度从0.332nm降至0.208nm.
- 烯和氨酸被逐渐化,导致分子量较小的成分.
结论:
- 粉的酶性水解显著改变了其分子重量和链条长度分布.
- 这些修改有效地降低了纹理水平,从固体 (第7级) 到液体 (第3至第0级).
- 该研究为配制符合IDDSI特定质地要求的粉类液体食品提供了科学基础.
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