柚皮不同部分果胶的理化性质比较

Comparison of physicochemical properties of pectins extracted from different part of pomelo peel

以柚皮黄色部分与柚皮白色部分为原料,采用相同提取工艺分别提取其中的柚皮果胶,并对其理化性质进行比较。相同提取工艺下,黄、白柚皮果胶的酯化度分别为74.4%和80.3%,均为高酯果胶。相同条件下,黄柚皮果胶的溶解度大于白柚皮果胶;不同温度下,2种柚皮果胶的溶解度都超过60%,随温度升高呈现溶解度升高的趋势。2种柚皮果胶的溶解度随着pH增大呈下降的趋势;流变学试验结果表明,白柚皮果胶黏度大于黄柚皮果胶,均与果胶浓度正相关,在pH2~4、钙离子浓度为2%~2.5%时黏度较大;凝胶质构结果表明黄柚皮果胶易形成凝胶而白柚皮果胶不易胶凝。

Taking yellow part and white part of pomelo peel powder as raw material, use the same process to extract pomelo peel pectins and to study the physicochemical property of the pectin. The esterification degree of yellow part is 74.4% and white part is 80.3%, they all showed high-fat pectin. Under the same condition, the solubility of yellow pomelo peel pectin was greater than that of white pomelo peel petin. Under the different temperature, the solubility of both pectin were above 60%, and increased with the increase of temperature, but decreased with the pH up. The rheological results showed that the viscosity of white pomelo peel pectin was greater than that of yellow pomelo peel pectin, which was positively correlated with pectin concentration. When pH 2~4 and calcium concentration were 2%~2.5%, the viscosity of both pectin were larger. Gel texture results showed that pectin of yellow pomelo peel was easy to form gel than the white.