ATP as an indicator of microbial contamination in crushing juices

Adenosine triphosphate (ATP) is a good indicator of living .cells and its use in the food industry for testing sterility is becoming commonplace. ATP measurements carried out at Victoria Mill, a mill with two crushing trains, showed that there was no significant difference between the two milling trains. Good correlations were obtained for ATP measurements and plate counts in laboratory shake flask trials, indicating . that the method is useful for estimating microbial contamination. R-squared values between plate counts and ATP measurements at the sampling points in the milling train were low, suggesting that the method requires further modification for use in the mill. Microbial ATP levels were shown to increase as the cut-to-crush time increased and steady rain falling before harvesting caused levels to increase 5 to 10 fold. Slime sampled from the walls of the first mills during a shutdown had relatively high ATP counts when compared to flowing juice. Possible uses for this technology in the raw sugar industry include rapid identification of stale cane/juice and evaluation of general hygiene standards around milling equipment.