Compounds determining pH in dry sausage.

The relative importance of various compounds determining pH in dry sausage was investigated using 'multiple linear regression' analysis. Analytical data were obtained for the concentrations of water, lactate, ammonia, acetate, α-amino nitrogen and salt related to sausage crude protein, using 55 different brands of dry sausage. The pH (Y) was significantly related to water, ammonia and lactate concentrations as follows: Y = 4·317 - 1·152X(1) + 0·751X(2) where X(1) = log(H(2)O) and X(2) = [log (ammonia)/(lactate) · 100] with (H(2)O) expressed as g/100g crude protein and (lactate) and (ammonia) as mmoles/100 g crude protein. The results suggest that the increase in pH often observed in the later stages of ripening is related to a decrease in electrolyte dissociation and/or an increase in the concentration of buffering proteins as well as to the formation of ammonia.