Effect of compositional and environmental fractors on the growth of indigenous non-starter lactic acid bacteria in Cheddar cheese

The effects of salt and moisture content, ripening temperature and starter strain, independently, on the growth of indigenous non-starter lactic acid bacteria (NSLAB) in Cheddar cheeses were studied. Salt-in-moisture (S/M) ≤ 5.9% had no effect on the growth of NSLAB; 6.1% S/M reduced their growth rate but had no effect on their number at 6 months. Cheeses with a moisture content > 40.3% had higher numbers of NSLAB than cheeses with a lower moisture content during the initial stages of ripening; the difference appeared to be related to the length of the lag phase rather than to the rate of growth of these bacteria. Numbers of NSLAB were quite low in cheeses ripened at 4 °C even after 6 months and increased with ripening temperature at all stages of ripening. NSLAB grew faster initially in cheeses made with Lactococcus lactis ssp lactis ML3 or 303 as starter than in those made with Lc lactis ssp cremoris AMI or AM2 but reached similar numbers after 6 months.