Effect of carbon dioxide on improving the keeping quality of raw milk

Fresh cows' milk samples were treated with CO2 to give a calculated CO2 content of 77mM. The treated samples as well as the control were stored at 7° and 20 ± 5°C for three days and analysed periodically. The increase in the total count as well as the counts of psychrotrophic, lactic acid and coliform bacteria during storage at 7°C was found to be inhibited by the addition of CO2. The treated samples had higher titratable acidity and lower pH values than the controls but satisfied the clot‐on‐boiling test. The keeping quality of cooled milk can therefore be improved by the addition of CO2.