Effects of processing and product handling on the prevalence of Campylobacter jejuni in turkeys and turkey products

Abstract

A selective enrichment-plating Most Probable Number (MPN) procedure was utilized to determine the prevalence of C. jejuni at various stages of turkey processing. Varying percentages of turkeys contained C. jejuni upon entering the processing plant. Large numbers of C. jejuni were killed during carcass scalding operations, but mechanical picking caused recontamination. Numbers of C. jejuni peaked during evisceration, but dropped to lower levels after washing. Few or no recoverable C. jejuni remained on carcasses after the chill tank. Very small numbers of C. jejuni were found on some turkey carcasses soon after freezing, but no C. jejuni were detected on retail frozen turkey carcasses. C. jejuni could be recovered in small numbers from initial stages of further processing. These numbers diminished until C. jejuni could no longer be recovered from further processed products including turkey wieners, turkey ham, and boneless breast. These products were eventually cooked at the processing plant and received adequate heat processing to destroy C. jejuni. Studies were conducted to find the location of C. jejuni contamination on turkey carcasses. Contamination of carcasses occurred on the surface of the skin or on the surface of the body cavity lining. No contamination of interior muscle tissue occurred. Proper roasting, braising, and stewing of turkey meat destroyed C. jejuni. However, the destruction of C. jejuni in foods by microwave cooking was assured only if the degree of "doneness" was judged by internal temperature rather than by visual appearance. Most washing procedures used for cleaning utensils were found to adequately remove C. jejuni from utensils, but some handwashing procedures failed to remove C. jejuni contamination from food preparers' hands. When C. jejuni was present on wholesale and retail frozen, ready-to-cook turkey carcasses, it was only recovered from drip collected in the package. Because of the heat sensitivity of the organism, remaining C. jejuni would be destroyed by cooking. This indicates if foodborne illness from C. jejuni occurs from consumption of turkey products, the final cooked product, in most cases, is cross-contaminated and the source of the organism is probably juice or drip from the raw turkey product.