摘要
以商品柑橘果胶为对照,利用QB2484-2000/GB2553-2010中的方法测定了八月瓜果胶的干燥失重、灰发含量、酸不溶灰发、pH、酯化度、半乳糖醛酸和溶解度;测定了八月瓜果胶粘均分子量,并通过傅里叶红外光谱分析果胶分子中的主要官能团;最后考察了温度、浓度、pH、不同食品添加剂对八月瓜果胶粘度的影响.结果表明:八月瓜果胶干燥失重10.89%、灰发含量4.17%、酸不溶灰发0.94%、pH为2.92、酯化度82.84%、半乳糖醛酸81.35%,溶解度84.66%,属于高脂果胶;粘均分子量为40万左右,红外光谱分析也证明为高脂果胶;八月瓜的粘度随着加热时间的延长而下降;八月瓜果胶的粘度与其质量浓度、蔗糖质量浓度成正相关,与温度、柠檬酸质量浓度、氯化钠质量浓度呈负相关,而随着pH值和CaCl_2质量浓度呈现出先增大后减少的趋势.因此本文对八月瓜果皮中提取的果胶提供了性能测试方面的参考价值.
Using commercial citrus pectin as control for comparison,loss on drying,ash,acid insoluble ash,pH,degree of esterification,galacturonic acid and solubility of akebia trifoliata pectin were deter-mined by QB2484-2000/GB2553-2010 standard;determination of viscosity average molecular weight and infrared spectrum analysis of akebia trifoliata pectin;the effects of temperature,concentration,pH and different food additives on the viscosity of pectin were examined.The results showed that loss on drying was 10.89%,ash was 4.17%,acid insoluble ash content was 0.94%,pH was 2.92,esterification degree was 82.84%,the total galacturonic acid was 81.35%,solubility was 84.66%,and it was a high methoxyl pectin.The viscosity average molecular weight is about 400,000,and the infrared spectrum analysis also proves to be a high methoxyl pectin.Its viscosity gradually decreased with increasing heating time;the viscosity of akebia trifoliata pectin was positively correlated with its concentration and sucrose concentration but negatively correlated with temperature,sodium chloride concentration and citric acid concentration displayed an initial increase and a subsequent decrease with increasing pH and calcium chloride concentration.
作者
石兵艳
赵飞
王芸
刘毅
李祥
SHI Bing-yan;ZHAO Fei;WANG Yun;LIU Yi;LI Xiang(College of Chemistry and Chemical Engineering,Agriculture and Forestry Technology Promotion Engineering Center,Shaanxi University of Science & Technology,Xi′an 710021,China)
出处
《陕西科技大学学报》
CAS
2019年第3期39-46,共8页
Journal of Shaanxi University of Science & Technology
基金
陕西省科技厅重点研发计划项目(2018ZDCXL-N-19-1
2018ZDXM-NY-007
S2019-ZC-XY-0003)
陕西省教育厅科研计划项目(18JC007)
关键词
八月瓜
果胶
理化性质
粘度
akebia trifoliate
pectin
physicochemical properties
viscosity
