Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011.
J Agric Food Chem. 2009 Mar 11;57(5):2040-8. doi: 10.1021/jf8033682.
Four corn types with different doses of mutant amylose-extender (ae) and floury-1 (fl1) alleles, in the endosperm, including no. 1, aeaeae; no. 2, fl1fl1fl1; no. 3, aeaefl1; and no. 4, fl1fl1ae, were developed for use in making Hispanic food products with high resistant starch (RS) content. The RS percentages in the native starch (NS) of 1-4 were 55.2, 1.1, 5.7, and 1.1%, respectively. All NS were evaluated for pasting properties with a rapid viscoanalyzer (RVA) and for thermal properties with a differential scanning calorimeter (DSC). NS 1 had a low peak viscosity (PV) caused by incomplete gelatinization, whereas NS 3 had the greatest PV and breakdown of all four starch types. On the DSC, NS 2 had the lowest onset temperature and greatest enthalpy. NS 1 and 3 had similar onset and peak temperatures, both higher than those of NS 2 and 4. The gel strength of NS heated with a RVA was evaluated by using a texture analyzer immediately after RVA heating (fresh, RVA-F) and after the gel had been stored at 4 degrees C for 10 days (retrograded, RVA-R). NS 1 gel was watery and had the lowest strength (30 g) among starch gel types. NS 3 gel, although exhibiting syneresis, had greater gel strength than NS 2 and 4. The structures of the NS, the RS isolated from the NS (RS-NS), the RS isolated from RVA-F (RS-RVA-F), and the RS isolated from RVA-R (RS-RVA-R) were evaluated by using size exclusion chromatography. NS 1 had a greater percentage of amylose (AM) (58.3%) than the other NS (20.4-26.8%). The RS from all NS types (RS-NS) had a lower percentage of amylopectin (AP) and a greater percentage of low molecular weight (MW) AM than was present in the original NS materials. The RS-RVA-R from all starches had no AP or high MW AM. The percentages of longer chain lengths (DP 35-60) of NS were greater in 1 and 3 than in 2 and 4, and the percentages of smaller chain lengths (DP 10-20) were greater in 2 and 4 than in 1 and 3. In general, NS 3 seemed to have inherited some pasting, thermal, and structural characteristics from both NS 1 and 2, but was distinctly different from 4.
四种不同剂量突变型直链淀粉扩展（ae）和粉质-1（fl1）等位基因的玉米类型，在胚乳中，包括 1 号，aeaeae；2 号，fl1fl1fl1；3 号，aeafl1；4 号，fl1fl1ae，被开发用于制作富含抗性淀粉（RS）的西班牙裔食品。1-4 号原生淀粉（NS）的 RS 百分比分别为 55.2%、1.1%、5.7%和 1.1%。所有 NS 均用快速粘度分析仪（RVA）评估糊化特性，用差示扫描量热仪（DSC）评估热特性。NS1 的峰值粘度（PV）较低，原因是不完全糊化，而 NS3 的 PV 和所有四种淀粉类型的崩解度最大。在 DSC 上，NS2 的起始温度最低，焓值最大。NS1 和 3 的起始温度和峰值温度相似，均高于 NS2 和 4。用 RVA 加热 NS 后，立即用质构分析仪（新鲜，RVA-F）评估 NS 凝胶强度，并在凝胶在 4°C 下储存 10 天后（回生，RVA-R）评估凝胶强度。NS1 凝胶呈水样，凝胶强度在淀粉凝胶类型中最低（30g）。尽管 NS3 凝胶有渗出，但凝胶强度大于 NS2 和 4。用凝胶渗透色谱法评估 NS、从 NS 中分离出的 RS（RS-NS）、从 RVA-F 中分离出的 RS（RS-RVA-F）和从 RVA-R 中分离出的 RS（RS-RVA-R）的结构。NS1 的直链淀粉（AM）百分比（58.3%）高于其他 NS（20.4-26.8%）。所有 NS 类型的 RS（RS-NS）的支链淀粉（AP）百分比较低，低分子量（MW）AM 百分比高于原始 NS 材料。所有淀粉的 RS-RVA-R 均不含 AP 或高 MW AM。NS1 和 3 的长链长度（DP 35-60）百分比大于 NS2 和 4，而 NS2 和 4 的短链长度（DP 10-20）百分比大于 NS1 和 3。一般来说，NS3 似乎从 NS1 和 2 遗传了一些糊化、热和结构特性，但与 4 号明显不同。
