Reducing Campylobacter numbers on chicken carcasses using lactic acid in processing plants

Four trials were carried out at a broiler processing plant to examine the effectiveness of spraying lactic acid solutions for reducing the numbers of Campylobacter on carcasses. The carcasses were naturally contaminated and treated after the inside-outside washer and before the air chiller. Carcasses were treated by spraying in a tunnel or with one of two hand-held sprayers. Carcasses were treated with a 1.9%, 4% or 8% solution of lactic acid buffered to pH 4 using sodium lactate, and testing was carried out on skin samples from the breast or back/neck. Treating carcasses with 1.9% acid was not effective. Treatments with 4% acid reduced the numbers of Campylobacter on breast skin by 0.4 log₁₀ cfu g^-1 or less and on back/neck skin by 0.8 log₁₀ cfu g^-1. Spraying with an 8% acid solution in the tunnel produced a 1.9-log cfu g^-1 reduction on breast skin but adversely affected the appearance of the carcasses. Further work is suggested with a 5% solution with consumer testing for acceptability of appearance.