以葡萄糖為原料生產酒精之醱酵策略

Fermentation strategies for ethanol production from glucose

周霖宏(Chou Lin-Hung)

指導教授 ： 段國仁

大同大學/工程學院/生物工程學系所/碩士(2008年)

摘要

本研究使用一株Lasaffre活性乾酵母Ethanol-RedTM，進行酒精的醱酵，實驗中以氧化還原電極來控制醱酵時培養液的通氣，結果發現將氧化還原電位(Oxidation-Reduction Potential, ORP)控制在- 155 ~ - 160 mV，能兼顧酒精的產率以及細胞生長。
當培養液的葡萄糖起始濃度為150、250、350 g/L，利用通氣控制ORP在- 155 ~ - 160 mV，醱酵結束的時間為20、33及82小時，酒精濃度分別為58.5、104.46、132.19 g/L。比較厭氧醱酵，在葡萄糖起始濃度150、250、350 g/L的醱酵結束時間為24、49及121小時，酒精濃度分別為63.33、106.3、130.6 g/L，厭氧醱酵所需時間比微量通氣增加18、52及53 %。在酒精產率方面，厭氧醱酵比微量通氣增加8.8、1.6、- 0.7 %。本研究結果也顯示葡萄糖濃度為250 g/L在微量通氣的環境下，可以得到最高的酒精生產速率為3.2 gL-1h-1。
本研究也探討酵母菌Ethanol-RedTM在32、37、40 ℃的環境下進行酒精醱酵的試驗，這是為了節省夏天進行酒精醱酵時，維持醱酵槽溫度的電力消耗，發現高溫(大於37 ℃)不利於酵母菌細胞的生長，但對酒精的產率並無太大的影響，若接種大量(5 g/L以上)的活性乾酵母，也能有效率的進行酒精的生產。

關鍵詞：通氣、酒精醱酵、高溫醱酵、氧化還原電位、酵母菌

關鍵字

通氣 ； 酒精醱酵 ； 高溫醱酵 ； 氧化還原電位 ； 酵母菌

並列摘要

This study employed an active dry yeast Ethanol-RedTM from Lasaffre in ethanol production. The oxidation reduction potential (ORP) was used to control aeration in the fermentation system. It was found that aeration controlled by ORP at - 155 ~ - 160 mV could promote yeast propagation, and did not reduce ethanol yield from glucose.
Three ethanol production experiments were performed for the initial glucose concentration of 150, 250, 350 g/L in aeration condition controlled by ORP at - 155 ~ - 160 mV. It took 20, 33, 82 h to consume glucose completely, and the ethanol concentrations were 58.5, 104.46, 132.19 g/L respectively in areobic condition. Whereas it took 24, 49, 121 h to finish the fermentation, and ethanol concentration was 63.33, 106.3, 130.6 g/L respectively in anaerobic condition. The fermentation time of anaerobic condition was 18, 52 and 53 % more than those of areobic condition. The final ethanol concentration of anaerobic condition was 8.8, 1.6, - 0.7 % more than those of aeration condition. The highest ethanol productivity was 3.2 gL-1h-1 when the initial glucose concentration was 250 g/L in aeration condition.
In order to reduce electricity in maintaining the fermenter temperature at 27 ~ 32 ℃ of the regular process for ethanol production in the summer, fermentation temperature more than 37 ℃ might be necessary. We performed the fermentation using Ethanol-RedTM at 32, 37, 40 ℃ in ethanol production. It was found that temperature more than 37 ℃ could inhibit yeast propagation, but did not reduce the ethanol yield from glucose very much. It could produce ethanol efficiently if we pitch more than 1 g/L active dry yeast in the fermentation.

Keywords: Aeration、Ethanol fermentation、High temperature fermentation、Oxidation reduction potential、Yeast

並列關鍵字

Aeration ； Ethanol fermentation ； High temperature

參考文獻

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