大豆浓缩磷脂的马来酸酐酰化改性研究

MALEIC ANHYDRIDE ACYLATED MODIFICATION OF CONDENSED SOYBEAN PHOSPHOLIPIDS

以马来酸酐为酰化试剂,与大豆浓缩磷脂进行酰化改性反应,探讨了马来酸酐用量、反应时间、反应温度等对浓缩磷脂酰化改性的影响.结果表明：酰化试剂用量为5%,时间为30 min,温度为55℃时,浓缩磷脂的酸价从18.45 mg/g升至58.85 mg/g,酰化率达87.35%,再用碱中和酰化磷脂降低酸价.由红外光谱测定酰化改性磷脂结构可知：在1 500-1 700 cm-1有吸收峰,即酰胺基团的引入;比拟法测定HLB值达5～7,乳化性能有明显的提高和改善.

The present study was to investigate the modification the phospholipids using maleic anhydride as acylating agent. Discussed the effect of the reaction time, temperature and the amount of maleic anhydride on the modification reaction. The results of GC and HPLC showed that the composition and content of the condensed phospholipids was phosphatidyl ethanolamine （PE） with 16.56%, phosphatidyl choline （PC） with 20.17%, phosphatidic acid （PA） with 6.58% and phosphatidylinositol （PI） with 11.36%. The fatty acid composition and content was palmitic acid with 15.77%, stearic acid with 4.38%, oleic acid with 16.17%, lenoleic acid with 56.86% and lenolenic acid with 6.69%. The optimized reaction conditions were as follows： acylating reagent dosage of 5%, the reaction time of 30min and the reaction temperature of 55 ℃. And under these conditions, the acylation rate was up to 87.35% while the acid value of phospholipids increased from 18.45 mgKOH· g-1 to 58.85 mgKOH ·g-1. The infrared spectrum results showed that there was a new absorption peak generated at 1500-1700 cm-1 which indicated that amide groups were brought into the acylated modified phospholipids. The mechanism of the modification was that the acylated reaction made the amide groups introduced into the phosphatidyl ethanolamine, which made the weight of the phospholipid molecules increased. It was concluded that the modification made the thermal stability, the hydrophilic performance, the ability of aqueous coating and the emulsion stability of the phospholipids increased and the HLB value of 5-7.