FERMENTATION OF RAW POULTRY BY-PRODUCTS FOR ANIMAL NUTRITION

In this study, the fermentation of raw, inedible poultry byproducts mi xed with sugarbeet pulp and dextrose and inoculated with Lactobacillus plantarum and(or) Enteroccocus faecium resulted in a drop of pH in th e byproducts to approximately 4.0 to 4.5 within 48 h. To keep the ferm ented product stable for a period of 21 d, the addition of greater-tha n-or-equal-to 3% (wt/wt) of a fermentable carbohydrate was necessary. With a high inoculation level of approximately 10(8) to 10(9) L. plant arum per gram, or with acidification of the initial mixture with.4% la ctic acid, the number of Enterobacteriaceae decreased faster than with inoculation at 10(6) L. plantarum per gram, or without initial acidif ication. After 21 d of fermentation, a high level of enzymatic breakdo wn of proteins and amino acids was observed: the nonprotein N level in creased from 5% to between 15 and 40% of total N and the volatile N le vel increased from 1% to between 3 and 11% of total N. An increase in histamine, cadaverine, and putrescine was also observed. Despite the t echnological measures taken, such as the application of a high inoculu m of starter culture and initial acidification with .4% lactic acid, t his amino acid breakdown could not be reduced to an acceptable level. These results suggest that, because of biochemical deterioration, ferm entation alone is not a useful method of preservation of raw poultry b yproducts.