塑性脂肪起砂及其控制  

Review on Formation Mechanisms of Granular Crystals in Plastic Fats and Its Control

作　　者：李琳[1,2,3] 万力婷[1] 李冰[1,2] 

机构地区：[1]华南理工大学食品科学与工程学院,广东广州510640 [2]广东省天然产物绿色加工与产品安全重点实验室,广东广州510640 [3]东莞理工学院,广东东莞523808

出　　处：《食品科学技术学报》2016年第2期1-11,共11页Journal of Food Science and Technology

基　　金：国家自然科学基金重点项目(31130042);国家自然科学基金青年基金项目(31401660);国家自然科学基金-广东省联合基金(U1501214)

摘　　要：塑性脂肪起砂严重影响其产品质量,研究起砂机制及其控制技术对优化工艺参数和改善产品品质等均具有重大意义。高熔点甘油三酯的迁移、聚集及β晶型转变是外部温度波动模式下塑性脂肪起砂的可能机制。油脂组成和加工及储运工艺参数如剪切速率、温度、冷却速率等均影响塑性脂肪起砂。控制起砂可通过油脂改性如油脂混合、酯交换和添加乳化剂等来降低高熔点甘油三酯的含量、稳定β'晶型。乳化剂与原料油甘油三酯之间主要通过"酰基-酰基"发生相互作用,当它们的酰基结构相似时可能共同结晶,而结构不同的地方则可能会延缓成核和抑制晶体生长;乳化剂对塑性脂肪结晶的作用受到其浓度和分子结构的强烈影响,过冷度过高时其作用会被削弱。The existence of granular crystals seriously impairs the quality of plastic fats, and consequent- ly, it is important to investigate the formation mechanisms and inhibitions of granular crystals in order to optimize the processing parameters and improve the product properties. The migration and aggregation of high-melting triglyeerides as well as β polymorphism evolution are the possible mechanisms for the forma- tion of granular crystals when temperature fluctuates. The fats composition and processing parameters have influences on the granular crystals formation such as shearing rates, temperature, cooling rates. To prevent their generation, modifying lipids by blending and interesterification and the application of emul- sifiers were adopted to reduce the content of the high-melting triglycerides and stabilize the β polymor- phism. Emulsifiers are mainly associated with the triglycerides present in the fat through acyl-acyl inter- actions, thus the chemical structures＇ similarity between the acyl groups would likely promote the eocrys- tallization, while the dissimilarities in fats structure might delay the nucleation and possibly inhibit crystal growth. Emulsifiers have different effects on the crystallization of plastic fats which strongly depend on their concentration and the molecular structure. In addition, when the degree of undercooling is high e- nough, addictive effects of emulsifiers will be weakened.

关 键 词：塑性脂肪 起砂 甘油三酯 同质多晶 控制 酯交换 乳化剂 

分 类 号：TS221[轻工技术与工程—粮食、油脂及植物蛋白工程]