利用淀粉加工工业废水研制微生物油脂

Investigation on production of microbial oils using industrial wastewater in starch processing

通过研究圆红冬孢酵母（Rhodosporidium Toruloides AS 2.1389）、油脂酵母（Lipomyces starkeyi AS 2.1390）、粘红酵母（Rhodotorula glutinis AS 2.703）、少根根霉（Rhizopus arrhizus）、畸雌腐霉（Pythium irregulare）、雅致枝霉（Thamnidium elegans）利用淀粉加工工业废水的产油特性,筛选出油脂含量最高的菌种。借助生物技术手段,利用微生物发酵方法,把使用价值较低淀粉加工工业废水转化为食用油脂。实验结果表明,粘红酵母的油脂含量最高,生物量、COD去除率也较高。最适菌种的最适培养条件为：在淀粉废水中加入15%废糖蜜,起始pH控制在6.0~7.0,在30℃温度下发酵7d,油脂积累最高,菌体生长量也较高。微生物油脂提取方法采用酸热法,酸热法单位时间内处理样品的能力远高于SCF-CO2法,且设备要求低。毛油经过脱胶、碱炼、脱色、脱臭后,油脂的酸值（AV）、过氧化值（POV）指标大大降低,色泽也得到一定改观。

In this study, the oibproducing properties of rhodosporidium toruloides （AS 2. 1389）, lipomyces starkeyi （AS 2. 1390）, rhodotorula glutinis （AS 2. 703）, rhizopus arrhizus, pythium irregular and thamnidium elegans utilizing wastewater of starch processing industry was investigated. With the help of biological technology, the low use value industrial wastewater in starch processing could be converted into edible oils and fats using the method of microorganism fermentation. The results showed that the oil content of rhodotorula glutinis was the highest, and biomass and removal rate of COD was also high. The optimum culture conditions were 15% waste molasses into wastewater, initial pH 6. 0 - 7. 0, and 7 d of fermentation at 30 ℃. Under the conditions, the oil accumulation was the highest, and bacteria growth mass was also higher. Microbial oils were extracted by acid-heating method, for its higher efficient capacity compared with the SCF-CO2 method and low requirements for equipment. After degumming, alkali refining, decolorization and deodorization, the acid value （AV） and peroxide value （POV） index of the oil was significantly reduced, and the color of oil also get a certain improvement.