MICROBIAL DEGRADATION OF HORN MEAL WITH BACILLUS SUBTILIS AND ITS APPLICATION IN LEATHER PROCESSING:A TWO FOLD APPROACH

摘要

Horn meal hydrolysate, obtained by high steam pressure treatment of raw horns and hoofs of cattle and buffalo, yields a mixture of water soluble peptides by microbial degradation using native strain of Bacillus subtilis. It is designated as Bacterial Degraded Horn Meal Hydrolysate (BDHH). BDHH stores well and does not putrefy when left at ambient conditions of temperature (32±3℃) and relative humidity (40-80% RH). This material is employed with great success in leather tanning process to improve the exhaustion of chrome and to fill the void within the tanned collagen fibers during retanning operation. Use of BDHH in leather processing could cut down consumption of chromium salts in chrome tanning by considerably reducing the discharge of chromium in the waste liquor from 30-35% to less than 10%, thus saving cost on chromium salts and reducing the pollution load in commercial tanning operations. Filling of tanned leather with BDHH in retanning operation upgrades the crust leather.