A preliminary investigation of the importance of clostridia in the production of rancid flavour in Cheddar cheese

Summary Bacteriological examination of 15 pairs of Cheddar cheeses, of which one of each pair was made aseptically, showed that there was a relationship between the development of rancid flavour and the numbers ofClostridium tyrobutyricumpresent. Other species of clostridia,Cl. beijerinkii, Cl. sporogenesandCl. perfringens, were also present but occurred only as spores. Conditions for the growth ofCl. tyrobutyricumappeared to be more favourable in the aseptically made cheese; it is suggested that the adventitious bacterial flora of the non-aseptically made cheese, which gains access during cheesemaking, has some inhibitory effect on the growth of this organism.