79. Studies in Cheddar Cheese. II. The Effect of Controlled Oxidation-reduction Potential on Ripening. III. The Rôle of Rennin, Pepsin and Lactobacilli

Abstract

II. When added as an oxidant to cheese, copper, to the extent of 36 p.p.m., produced an abnormal flavour and markedly inhibited the ripening process. The remaining oxidants (KNO 3 , KCIO 3 and KCIO 4 ) held the cheese at a higher potential and decreased the amount of proteolysis, especially after five months. Potassium cyanide had no effect on the proteolysis or the oxidation-reduction potential. It is concluded, therefore, that normally the flora of cheese holds the oxidation-reduction potential at such a point that proteolysis is diminished if the potential is raised to the oxidative side. III. Variations in the amounts of pepsin and rennin appeared to have little effect on flavour, texture, body or ripening. There was apparently no correlation between clotting time and extent of proteolysis. The addition of lactobacilli with the starter appeared to accelerate the protein degradation in the early stages of ripening.