Cheddar Cheese Manufacture with Pepsin and Rennet1

Rennet was compared with a mixture (1:1) of rennet and pepsin in making and curing Cheddar cheese. Eight pairs of vats of cheese were made in each of four factories. Coagulation of milk with the mixture was slower than with rennet in only one factory. Fat losses in the whey in two factories were slightly higher where the mixture was used, but not in the other two factories. Federal graders examined the cheese at 3 weeks, 6 and 12 months of age. The texture of “mixture” cheese was slightly poorer than that of rennet cheese when 3 weeks old. Flavor scores were slightly higher for “mixture” cheese than for rennet cheese when 12 months old. Taste panels revealed only very slight differences in intensities of Cheddar flavor and of bitter flavor when the cheese was 12 months old. “Mixture” cheese was slightly firmer than rennet cheese at 6 and 12 months. Protein hydrolysis was less in “mixture” cheese than in “rennet” cheese made in some factories. Observations are also given for cheese made in four paired vats with rennet and with pepsin only.

It was concluded that the mixture (1:1) of rennet and pepsin produced cheese of high quality, essentially equal to that made with rennet, and that pepsin should not be used alone without further trials. The results indicated that cheesemakers should give more attention, when using the mixture, to factors affecting texture of cheese and fat losses in the whey, and that problems might be encountered with slow coagulation of the milk.