Abstract：
The pectin was extracted using H2SO4, HNO3, and HCl from the pulp of four coffee varieties (Harar, Sidama, Jimma, and Guji) collected from different regions of Ethiopia. The effect of extraction temperature, time, solid-to-liquid ratio, types of acid and coffee varieties on the physiochemical properties and yield of pectin were studied. A maximum pectin yield, which was 12.7 %, was obtained from Harar coffee pulp treated with H2SO4. The equivalent weight of the extracted pectin varied from 1111 to 1667 g/mol. The methoxyl contents of the extracted pectin ranged from 4.23 to 7.13 %. The degrees of esterification and anhydrouronic acid of the pectin ranged from 53 to 68.5 % and 35.5 to 68.8 %, respectively. The results show the yield and physiochemical properties of the coffee pulp pectin depend on extraction parameters, acid types, and coffee varieties. Moreover, the pectin extracted from coffee pulp showed strong gelling properties.
摘要：
使用H2SO4，HNO3和HCl从四个咖啡品种的果肉中提取果胶（Harar，西达玛,Jimma,和古吉）从埃塞俄比亚的不同地区收集。提取温度的影响,时间,固液比，研究了酸和咖啡品种对果胶理化性质和产量的影响。最大果胶产量，是12.7%,从用H2SO4处理的Harar咖啡浆获得。提取的果胶的当量重量在1111至1667g/mol之间变化。提取的果胶的甲氧基含量为4.23-7.13%。果胶的酯化度和脱水糖醛酸的范围为53至68.5％和35.5至68.8％，分别。结果表明，咖啡浆果胶的产量和理化性质取决于提取参数，酸类型，和咖啡品种。此外，从咖啡浆中提取的果胶具有很强的胶凝特性。
