The effect of certain amino acids and browning inhibitors on the 'black spot' phenomenon produced by Carnimonas nigrificans

Black spots are sometimes observed in fermented sausages and raw cured meat products, with resultant economic loss. The effect brought about by some a mino acids in the development of this browning was evaluated, in aerobiosis at 30 degrees C and 90-95% RH, in a pork meat mixture with glucose, NaCl a nd inoculated with Carnimonas nigrificans CTCBS1(T) at 1.0 x 10(7) CFU g(-1 ). Amino acids and alternative substances to bisulphite and nitrite as prev entative agents were studied for their effect on the browning reaction. The effect of NaCl concentration on browning and on the growth of Carnimonas n igrificans CTCBS1(T) was also evaluated. Glycine, L-arginine, L-glutamine a nd L-monosodium glutamate were the amino acids that significantly decreased the L values and increased the browning scores in comminuted meat which wa s mixed with 40 gkg(-1) NaCl and 20 gkg(-1) D-(+)-, glucose and inoculated with Carnimonas nigrificans CTCBS1(T). N-acetyl-L-cysteine, L-cysteine, pot assium metabisulphite and propil-3, 4, 5-trihydroxybenzoate prevented brown ing at 10 and 5 gkg(-1). The optimum concentration of NaCl for the growth o f Carnimonas nigrificans CTCBS1(T) was 40 gkg(-1). (C) 2000 Society of Chem ical Industry.