Aging-Induced Changes in Populations of Lactococci, Lactobacilli, and Aerobic Microorganisms in Low-Fat and Full-Fat Cheddar Cheese†

Abstract

The objective of this study was to observe the impact of lowering fat content on the microflora of Cheddar cheese. Full-fat (32%) and low-fat (5%) Cheddar cheeses were produced and evaluated one day after manufacture and at monthly intervals for 5 months. The cheeses were aged at 4°C after being dipped in mold inhibitor and vacuum packed in high-density polythene bags. Standard plate counts and counts of lactococci and lactobacilli were performed. Transmission and scanning electron microscopy of the microflora were also conducted. The lactococci decreased gradually over the ripening period, while the lactobacilli, though not knowingly added during Cheddar cheese preparation, increased concomitantly. Transmission electron microscopic observations revealed affinity of lactococci for the fat phase in aged cheese.