提取工艺与果径对柑橘果胶多糖性质的影响

作为健康食品胶体,果胶需求连年增长,而柑橘罐头加工的脱囊衣工艺水是果胶新的重要来源。考虑到柑橘罐头的产品分级及酸碱脱囊衣工艺等差异对后续回收果胶的影响,本研究按柑橘罐头加工方法,以不同果实大小的柑橘囊衣为原料(大橘、中橘和小橘,分别对应果实横径7.3~7.7,5.9~6.3 cm和5.0~5.4 cm),研究了高温酸提(商品果胶工艺)及低温酸提(酸处理工艺)、低温碱提(碱处理工艺)对果胶的影响。结果表明,提取工艺对果胶性质影响大,低温碱提的果胶分子质量最大,中性糖含量最高;高温酸提果胶分子质量最小,中性糖含量最少;低温酸提的分子质量与中性糖含量均介于两者之间。柑橘果径对果胶的影响较小,大橘酸溶性果胶含量少于小橘,而碱溶性果胶相反,大橘果胶分子质量较小。提取工艺与柑橘原料的差异会影响所提果胶的性质,本研究为果胶提取提供了理论基础。

The Effect of Extraction Process and Fruit Size on the Characteristic of Mandarin Pectin

Pectin is widely used as a health food colloid with its demand growth for years.Recovery of pectin from the process water of mandarin canning is the important new way for pectin production.The different parameters in canning process,such as fruit size classification,acidic and alkaline process for segment membrane removal,will affect the following recovered pectin.Thus,pectin extraction from mandarin segment membrane with three fruit sizes(diameter of 7.3-7.7,5.9-6.3 cm and 5.0-5.4 cm),under three extraction processes,that is,high temperature acidic extraction(commercial pectin process),low temperature acidic extraction(mandarin canning acidic process),and low temperature alkaline extraction(mandarin canning alkaline process)were conducted.The results show that the extraction methods significantly affect pectin properties.Low-temperature alkaline extraction pectin has the highest of neutral sugar content and molecular weight,while high temperature acidic extraction pectin ranks the lowest of the above indexes.The fruit size has a small influence on the pectin.Large mandarin contains less acid soluble pectin and more alkali soluble pectin comparing to the small mandarin.In addition,the molecular weight of large mandarin pectin is smaller.Thus,extraction method and mandarin raw material differences will affect the properties of pectin.This work provides an important knowledge for pectin extraction.