Stabilization of poultry processing by-products and poultry carcasses through direct chemical acidification

Laboratory and field experiments were conducted to test the feasibility of using chemical acidification for stabilizing poultry-processing offal and blood and poultry carcasses. Acidification of the ground poultry materials with 2% (w/w) of 90% formic acid was the most economical method for preventing putrefactive changes and did not adversely affect crude protein and fat content. The acid-preserved offal and carcasses were stable semi-liquid/solid products with pHs of 4.0–4.2. When stored for 28 days at 30°C, the acidified offal and carcass products had approximately 67 and 62% moisture, 12 and 14% protein, 17 and 15% fat, and 0.16 and 0.23% ammonia, respectively. Several problems were identified, however, when the acid-treated offal was heat-processed to produce a dry feed meal.