Ao Zihua, Simsek Senay, Zhang Genyi, Venkatachalam Mahesh, Reuhs Bradley L, Hamaker Bruce R
Whistler Center for Carbohydrate Research and Department of Food Science, Purdue University, West Lafayette, Indiana 47907-2009, USA.
J Agric Food Chem. 2007 May 30;55(11):4540-7. doi: 10.1021/jf063123x. Epub 2007 May 8.
The hypothesis of increasing the branch density of starch to reduce its digestion rate through partial shortening of amylopectin exterior chains and the length of amylose was investigated. Starch products prepared using beta-amylase, beta-amylase and transglucosidase, maltogenic alpha-amylase, and maltogenic alpha-amylase and transglucosidase showed significant reduction of rapidly digested starch by 14.5%, 29.0%, 19.8%, and 31.0% with a concomitant increase of slowly digested starch by 9.0%, 19.7%, 5.7%, and 11.0%, respectively. The resistant starch content increased from 5.1% to 13.5% in treated starches. The total contents of the prebiotics isomaltose, isomaltotriose, and panose (Isomaltooligosaccharides) were 2.3% and 5.5%, respectively, for beta-amylase/transglucosidase- and maltogenic alpha-amylase/transglucosidase-treated starches. The molecular weight distribution of enzyme-treated starches and their debranched chain length distributions, analyzed using high-performance size-exclusion chromatography with multiangle laser light scattering and refractive index detection (HPSEC-MALLS-RI) and HPSEC-RI, showed distinctly different patterns among starches with different enzyme treatments. A larger proportion of low molecular weight fractions appeared in starches treated additionally with transglucosidase. All enzyme-treated starches showed a mixture of B- and V-type X-ray diffraction patterns, and 1H NMR spectra showed a significant increase of alpha-1,6 linkages. Both the increase of the starch branch density and the crystalline structure in the treated starches likely contribute to their slow digestion property.
研究了通过部分缩短支链淀粉外部链和直链淀粉长度来增加淀粉分支密度以降低其消化率的假说。使用β-淀粉酶、β-淀粉酶和转葡萄糖苷酶、麦芽ogenicα-淀粉酶以及麦芽ogenicα-淀粉酶和转葡萄糖苷酶制备的淀粉产品显示，快速消化淀粉显著降低了14.5%、29.0%、19.8%和31.0%，同时缓慢消化淀粉分别增加了9.0%、19.7%、5.7%和11.0%。处理后的淀粉中抗性淀粉含量从5.1%增加到13.5%。对于β-淀粉酶/转葡萄糖苷酶和麦芽ogenicα-淀粉酶/转葡萄糖苷酶处理的淀粉，益生元异麦芽糖、异麦芽三糖和潘糖（异麦芽低聚糖）的总含量分别为2.3%和5.5%。使用带多角度激光光散射和折射率检测的高效尺寸排阻色谱（HPSEC-MALLS-RI）和HPSEC-RI分析的酶处理淀粉的分子量分布及其去分支链长度分布，在不同酶处理的淀粉之间显示出明显不同的模式。在另外用转葡萄糖苷酶处理的淀粉中出现了更大比例的低分子量级分。所有酶处理的淀粉都显示出B型和V型X射线衍射图案的混合，并且1H NMR光谱显示α-1,6键显著增加。处理后淀粉中淀粉分支密度的增加和晶体结构可能都有助于它们的缓慢消化特性。
