大豆油脱臭馏出物酯化处理的试验研究

Studies on Esterification Treatment of Soybean Deodorized Distillate

酯化处理是利用超临界CO_2从豆油脱臭馏出物中提取维生素E的重要步骤之一,常用甲酯化方法进行酯化处理,然而因甲醇有剧毒,处理过程有诸多不便。本文探讨了乙酯化处理的可能性。结果表明:影响乙酯化率的主要因素是乙醇与豆油脱臭馏出物的重量比例、酯化温度和酯化时间,催化剂硫酸浓度对其影响较小。最佳酯化因素组合是:乙醇与豆油脱臭馏出物的重量比例为0.6、硫酸浓度1％、酯化温度80℃、酯化时间60min,在此务件下,最高酯化率可达74.5％。影响维生素E损失率的最主要因素是酯化时间和酯化温度,乙醇与豆油脱臭馏出物的重量比例和硫酸浓度对其影响较小。在乙酯化过程中,维生素E损失的最小值为4.18％。

Esterification is one of the most important steps in the process of natural vitamin E extraction using supercritical carbon dioxide from soybean deodorized distillate (SDD) . The common method is methanol esterification, but methanol is strongly toxic which gives much difficulty to the esterification process. The feasibility of ethanol esterification was studied in this paper. The results showed that the important factors affecting the esterification ratio were the weight ratio of alcohol and SDD, esterification temperature and esterification time, while sulfuric acid concentration has a little influence. The best factor combination was: the weight ratio of alcohol to SDD 0.6, sulfuric acid concentration 1%, esterification temperature 80℃ and esterification time 60min, at this condition, the highest esterification ratio was 74.5%. As to vitamin E loss during esterification, the most important factors are esterification temperature and time, while the weight ratio of alcohol and SDD, sulfuric acid concentration had minor effect. During esterification, the minimum vitamin E loss was just 4.18%.