The effect of evisceration on visible contamination and the microbiological profile of fresh broiler chicken carcasses using the Nu-Tech Evisceration System or the conventional Streamlined Inspection System

Abstract

Experiments were conducted to determine the effect of evisceration on visible contamination and the microbiological profile of fresh broiler chicken carcasses using the Nu-Tech System or the Streamlined Inspection System (SIS). Visible contamination was evaluated on the inside cavity and outside surface of 1,000 and 7,825 carcasses from Plants A and B, respectively, during 5 d of processing. For the microbiological study, in five separate trials, 80 broiler carcasses were collected each day from two processing plants (A and B). Two groups of 20 carcasses each were collected immediately prior to entering the Nu-Tech eviscerator, bagged separately, and 20 were labeled as NT1 and 20 as SIS1. The third group of 20 carcasses was collected immediately after the cropper on the Nu-Tech line and labeled NT2. For the fourth group, 20 carcasses were aseptically transferred from the Nu-Tech line just prior to evisceration, placed on the SIS line prior to evisceration, allowed to be eviscerated by the SIS eviscerator, collected immediately after the cropper, and labeled SIS2. Whole carcass rinses were conducted and aerobic plate counts (APC), total coliform counts (TC), total Escherichia coli counts (TEC), aerobic mesophilic impedance detection times (DT), and coliform impedance detection times (CDT) were determined within 30 h of collection. The Nu-Tech System was superior to SIS with regard to visible carcass contamination. For Plant A, evisceration using the Nu-Tech System or SIS did not significantly affect APC, TC, or TEC; however, evisceration using the Nu-Tech System resulted in an increase in DT and CDT (indicating a reduction in bacteria); whereas evisceration using SIS resulted in no significant decrease in bacterial levels. For Plant B, evisceration using the Nu-Tech resulted in lower APC, TC, TEC, and higher DT and CDT (indicating a reduction in bacteria); whereas evisceration using SIS resulted in no significant decrease in bacterial levels. Evisceration using the Nu-Tech System was at least equal to or in some cases better than SIS with regard to APC, TC, TEC, DT, and CDT.