In very high gravity (VHG) ethanol fermentation, the rheological properties of native cassava significantly influence heat and mass transfer, mixing energy, and, thus, the yield of all steps. This study investigated the effect of cassava varieties and their harvest times on starch liquefaction, saccharification, and fermentation. The genotype correlation of the starch properties was revealed for the most suitable cassava varieties. First, the starch content, amylose content, total reducing sugar from liquefaction and saccharification, pasting properties, and ethanol yields of six cassava varieties (Huay Bong 60, Hanatee, Kasetsart 50, Pirun 1, Pirun 2, and Rayong 11) at 6-, 9-, 12-, and 15-month harvest times were evaluated. The amylose content increased significantly from the 6th to the 12th month but slightly decreased at the 15th month. It was observed that the starch content contributed to a more substantial influence on the change in peak viscosity than on the amylose content. Ethanol fermentation using Saccharomyces cerevisiae TISTR5606 showed that the Rayong 11 variety at the 15-month harvest time provided the highest ethanol concentration of 104.7 ± 4.1 g L-1 and an ethanol yield of 0.4 ± 0.1 g ethanol g-1 reducing sugar, which corresponded to 74.5% of the theoretical yield.

中文翻译：

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高重力乙醇生产中木薯根的流变特性和基因型相关：木薯品种和收获时间的影响。

在非常高的重力（VHG）乙醇发酵中，天然木薯的流变特性会显着影响传热和传质，混合能以及所有步骤的收率。这项研究调查了木薯品种及其收获时间对淀粉液化，糖化和发酵的影响。对于最合适的木薯品种，揭示了淀粉特性的基因型相关性。首先，六个木薯品种（Huay Bong 60，Hanatee，Kasetsart 50，Pirun 1，Pirun 2和Rayong 11）的淀粉含量，直链淀粉含量，液化和糖化产生的总还原糖，糊化特性和乙醇产量（6-分别评估了9、12和15个月的收获时间。从第6个月到第12个月，直链淀粉含量显着增加，但是在第15个月，直链淀粉含量略有下降。观察到，淀粉含量对峰粘度的变化比对直链淀粉含量的影响更大。使用酿酒酵母TISTR5606进行的乙醇发酵显示，在15个月的收获时间，Rayong 11品种提供的最高乙醇浓度为104.7±4.1 g L-1，乙醇产量为0.4±0.1 g乙醇g-1还原糖，与达到理论收率的74.5％。