by Andy Muirhead, ALS Company Microbiologist.
Over the last few months we have reported on several novel ways to decontaminate and reduce the bacterial loading of fresh produce such as ultrasonic techniques and using cold plasma created ozone streams, but a recently published report in the Journal of Food Protection compares the two more traditional processes of chlorine and peracetic acid (PAA) in washing fresh produce.
The comparison was done at industrial scale, with equipment already present in the fresh-cut industry and using three product types; Iceberg lettuce, carrots and baby salad leaves. Results showed that, with regard to washing water hygiene and final product microbial quality, the use of PAA had a similar efficacy to chlorine.
The report did suggest however that after washing with 80mg/L of Chlorine, the residual Trihalomethanes (THM’s) exceeded the legal limits for this potentially carcinogenic by-product,and the report concluded that PAA is a reliable alternative to chlorine disinfection strategies in the fresh-cut industry.