酸法提取条件对苹果果胶理化特性的影响及机制

Effects of acid extraction conditions on the physicochemical properties of apple pectin and its mechanisms

近年来,苹果果胶因具有多种生理活性及优良的工艺学特性(凝胶、增稠等)而受到极大关注。按照结构决定功能的原理,苹果果胶的功能或工艺学特性是由其理化特性(分子质量、酯化度等)决定的,而原料特性(品种、成熟度等)和提取方法对苹果果胶的理化特性有很大的影响。鉴于酸法(酸溶醇沉)是工业上常用以皮渣为原料的苹果果胶提取方法,该文在文献的基础上,分析了酸法提取条件(提取剂种类及用量、液料比、温度、物理场种类与强度等)对苹果果胶提取率及其理化特性(酯化度、中性糖含量、半乳糖醛酸含量、分子质量等)的影响及机制。同时还对该领域存在的问题及发展方向进行了分析。

In recent years,apple pectin has received much attentions due to its diverse bioactivities and excellent technical properties as gelling and thickening agents. According to the general principle that the functionality is decided by the structure,the functional and technical properties of apple pectin were highly depended on the physicochemical characters,such as molecular weight and degree of esterification. Further,the physicochemical characters of an apple pectin product are heavily relied on the properties of raw materials（variety and maturity）and extraction method. At present,the acid method is the dominated industrial method to produce apple pectin with apple pomace. In performing this method,the pectin was first extracted with an acid solution and then precipitated by adding enough ethanol. In this context,by extensive reviewing relevant literatures,the effects of the acid extraction conditions（the type and dosage of extraction agent,liquid-solid ratio,extraction temperature,the type and the strength of physical field,etc.）on the extraction rate and physicochemical properties of apple pectin（the degree of esterification,neutral sugar content,galacturonic acid content,molecular weight,etc.）and their mechanisms were investigated. Meanwhile,the current problems and perspectives in the field are analyzed.