Standardization of eco-friendly technique for extraction of pectin from apple pomace

Abstract

Apple pomace, an industrial by-product generated from apple juice processing industries, is a good source of pectin. The method for pectin extraction has been standardized by autoclaving apple pomace flour for time intervals of 15, 30, 45 and 60 min at 121 °C. The extraction of pectin by using autoclave at 121°C for 60 min followed by precipitation with 95 % ethanol was found optimum with pectin yield of 13.01 % on dry weight basis and anhydrogalacturonic acid content of 43.21 %. The pectin extracted by using eco-friendly method is characterized by equivalent weight (942.04), methoxyl content (4.32 %), anhydrogalacturonic acid (43.21 %) and degree of esterification (56.76 %). However, autoclaving at 121 °C for 45 min also resulted in 12.97 % pectin, but on the basis of anhydrogalacturonic acid (%) contents, the autoclaving of pomace for 60 min was optimized. The standardized method can be used to replace the chemical extraction procedure for commercial extraction of pectin from apple pomace.