摘要
以浓硫酸为溶剂和催化剂,L-抗坏血酸和硬脂酸甲酯进行酯交换反应合成了L-抗坏血酸硬脂酸酯,产率可达77%。考察了反应温度、反应时间﹑反应物配比及浓硫酸用量对酯交换反应的影响。对产品的抗氧化性能进行了测定,结果表明L-抗坏血酸硬脂酸酯是一种优良的无毒食品抗氧化剂。
Oil is easy to be oxidized and become deteriorated and rancided because of its unsaturated fatty acids. As a kind of water-soluble antioxidant, L-ascorbic acid is difficult to be used for oil and foodstuff for its poor solubility in oil. However the L-ascorbyl stearate is easily soluble in oil and is an effective antioxidant. It can be widely used in oil, foods and other fields to prevent rancidity and deterioration. L-ascorbyl stearate was synthesized by the transesterification of L-ascorbic acid with methyl stearate using concentrated sulfuric acid as solvent and catalyst. The effect of reaction temperature, reaction time, ratio of reactant and amount of concentrated sulfuric acid on the transesterification was investigated. The experiment results show that 77% yield can be obtained under the following optimum synthetic conditions: molar ratio of L-ascorbic acid to methyl stearate 1:1.3, reaction time 24h, reaction temperature 24℃ and molar ratio of concentrated sulfuric acid to L-ascorbic acid and methyl stearate 1:0.15. The infrared spectrum and antioxidant effect of the product were also studied. The results show that L-ascoryl stearate is a good antioxidant without poison. Quality of the product is in conformity with the quality standard of FAO/WHO.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2002年第4期441-445,共5页
Journal of Chemical Engineering of Chinese Universities
