PROCESS FOR RECYCLING SLAUGHTERHOUSES WASTES AND BY-PRODUCTS BY FERMENTATION

Slaughterhouse wastes including animal and poultry wastes, were mixed separately with 15% molasses and inoculated with a starter culture of Lactobacillus plantarum. The mixture was incubated at 22-24 degrees C for 10-15 days. Physico-chemical and chemical determinations including pH, dry matter ash, Total Nitrogen (TN), Non Protein Nitrogen (NPN), Total Volatile Nitrogen (TVN), lipids and reducing sugars were determi ned on the products. In parallel, microbiological analyses, including standard plate count, coliforms, Salmonella, Clostridium, were also de termined daily. Results indicated that the product obtained from the a nimal wastes showed low counts of coliforms. Salmonella was not detect ed. Chemical determinations showed a net decrease of the pH and low le vels of total volatile nitrogen with a decrease in total sugars. Non p rotein nitrogen was high in the product relative to the raw material, while the product obtained from poultry by-products showed very intere sting data for both chemical and microbiological characteristics: that is, pH decrease to low levels was rapid and the preservation was ensu red by the net decrease in Gram negative bacteria and Clostridium, the absence of Salmonella and the stabilization of the standard plate cou nts. The product had a high level of fat and crude protein. (C) 1998 E lsevier Science Ltd.