固态间歇补料乙醇生料发酵新工艺

Dry solid staging fermentation

摘要:

浓醪发酵是酒精生产的发展方向。与现行酒精厂普遍采用的热蒸煮工艺相比, 生料发酵技术的发展使得浓醪发酵更容易进行。本研究首次在生料发酵中直接采用固态原料间歇补料, 比较了STARGENTM生淀粉水解酶间歇补料工艺和传统无补料工艺, 并对不同补料方式进行了研究。结果表明: 与传统无补料生料发酵工艺相比, 在相同的干基配料浓度30%、相同的生料酶添加量0.22%(W/W)的条件下, 采用15%的起始配料浓度、发酵15~25 h进行间歇补料的新工艺, 酒精产量从17.06%提高到18.50%。该间歇补料优化工艺的建立, 丰富了生料发酵技术的应用。

Abstract:

Very high gravity (VHG) ethanolic fermentation is a new perspective technology for the fuel ethanol production. Compared with traditional hot cook process in most ethanol plants, uncooked process using milled grain slurry in combination with granular starch hydrolyzing enzymes makes high gravity fermentation much easier to control. In this study, dry solids staging technique was first time reported in uncooked process for fermentation ethanol. We further studied the difference between the new process and the batch fermentation, including different initial fermentation concentrations and different starting times. The results showed that at the same dry solid concentration of 30% and the same enzyme dose at 0.22% (W/W), the final ethanol output of new process was increased to 18.50% ( V/V) from 17.06% (V/V) of the conventional process. This study demonstrated the new application of uncooked fermentation technology.