利用柑桔加工废弃物制取糖蜜及乙醇

柑桔加工废弃物约占果实质量的50%,含大量糖分,适宜制备糖蜜和发酵生产乙醇.研究了用废弃物制取糖蜜及生产乙醇的工艺和条件.结果表明,柑桔皮渣制取糖蜜时,生石灰的适宜添加量为0.3%,制得的可溶性固形物为40%的糖蜜,总糖含量为34%.对pH值、糖度、接菌量和温度等影响发酵的主要因素做单因素研究基础上开展了正交试验,得到柑桔糖蜜发酵的较佳工艺条件为：发酵液的初始pH 5.0,初始含糖量25%,接种量3×107个/mL,温度保持在30℃,静置发酵.由此获得含量为10.6%的乙醇产品,为探索用柑桔糖蜜生产燃料乙醇提供了参考.

Production of Molasses and Alcohol Using Citrus Processing Residues

The by-products of citrus fruits processing can be up to 50% of the fruit, which containing a lot of sugar that could be used to prepare molasses and be further fermented into alcohol. The conditions of producing malasses and alcohol were optimized. The amount of quicklime to extract syrup for preparing molasses from citrus processed residues was 0.3%. Molasses with 40% total soluble solid （TSS） was prepared in this study that contained 34% total sugar. The main factors affecting fermentation of the mo- lasses including pH, sugar level, inoculums size of yeast and temperature were studied by means of single factor test, and then an orthogonal test was conducted to optimize the conditions. Optimal fermentation conditions to produce ethanol from molasses were as follows, initial pH 5.0, initial sugar level 25% , in- oculums size 3 x 107/mL, fermentation temperature 30 ~C and standing fermentation. Under the optimal fermentation conditions, a level 10.6% of alcohol was obtained. The resuhs indicated that it＇s feasible to produce fuel alcohol by using molasses extracting from citrus residues.