Effect of Environmental Factors in Aerobiosis and Anaerobiosis on the Growth and Activity of Propionic Acid Bacteria Evaluated by Pressure Measurement

Abstract

AbstractThe effects of air, N2 and CO2 atmospheres on the growth and metabolism of P. shermanii CIP 10 30 27 under “optimum conditions” (pH 6.5, NaCl 0 %, temperature 30 °C) and “stressful conditions” (pH 5.3, NaCl 2.1 %, temperature 20 °C) simulating cheese ripening conditions were investigated using a pressure measurement technique. Under both conditions, the inhibition of growth was at its maximum when a CO2 atmosphere with an increase in the lag phase (LP) from 3 to 80 h and a reduction in the maximum rate of pressure variation (Vmax,P) from 2.5 to 0.4 kPa/h was used. The production of metabolites was not affected under “optimum conditions”, but under “stressful conditions”, propionate production increased and higher ratios of propionate to acetate of up to 2.45 were observed. The effects of air and N2 atmospheres on both growth and metabolite production were also examined.