响应面试验优化玉米油冷冻吸附法脱皂工艺

Optimization of Adsorption at Freezing Temperature for Reduced Soap Content in Corn Oil by Response Surface Methodology

对玉米油冷冻吸附法脱皂工艺进行研究,考察脱胶脱酸玉米油含皂量、含水量、硅藻土添加量、搅拌速率和养晶时间对冷冻吸附法脱皂后清油中残皂量的影响。通过单因素试验和响应面优化确定冷冻吸附脱皂的最佳工艺条件为:含皂量321 mg/kg、含水量0.4%、硅藻土添加量0.4%、搅拌速率12 r/min、养晶时间27 h。在此条件下,清油中的残皂量为23.1 mg/kg,脱皂率为92.8%。对冷冻吸附法脱皂工艺和常规水洗工艺的清油品质进行对比,结果表明,这两种方法脱皂的效果相当,但冷冻吸附脱皂不经过水洗过程,无废水排放,符合节能环保的工艺要求,并且利用冷冻吸附法脱皂能够完成前脱蜡的目的,简化了加工工艺。

This study was focused on reducing the soap content in corn oil by adsorption at freezing temperature. The effect of the soap content and water content in degummed and deacidified corn oil, the addition of different amounts of diatomite to the oil, stirring speed and crystal growing time on the soap residue after adsorption was examined. Using single factor experiments and response surface methodology, the optimal process conditions for removing soap from corn oil were determined as follows： addition of 0.4% diatomite to crude corn oil containing 321 mg/kg soap and 0.4% moisture, stirring at 12 r/min, and 27 h crystal growth. Under these conditions, the residual soap in the oil was 23.1 mg/kg, and 92.8% of the initial concentration was removed. The freeze-adsorption method was similarly effective as the conventional washing process in reducing the soap content as indicated by the comparison of oil quality. On the other hand, the new method did not need washing or drying. In addition, the method enabled pre-dewaxing and streamlined the processing steps. Without producing sewage, it accomplished the purpose of energy conservation and environmental protection.