| Poultry can be a vehicle for the transmission of salmonellosis and the contamination of carcasses is primarily from feces. Bactericidal treatments may be used to correct the problem. A study was conducted to evaluate the effectiveness of several bactericides (i.e., chlorine, trisodium phosphate, Avgard{dollar}sp{lcub}rm TM{rcub}{dollar} and lactic acid). Response surfaces showed that only lactic acid treatments significantly (p {dollar}>{dollar} 0.05) reduced both the total aerobic bacteria and coliform count. In a pilot scale study, lactic acid was used on contaminated carcasses at a concentration of 4.25% (w/w) and pH 3.0 with a dispensing temperature of 40{dollar}spcirc{dollar}C. The treatment significantly (p {dollar}>{dollar} 0.05) reduced carcass contamination. To determine the long term effects of lactic acid on viability and recovery of pathogens, Salmonella hadar was isolated from poultry and bioluminescent constructs obtained by transformation with the lux (CDABE) cassette. Viability was determined by measuring luminescence following lactic acid treatment of turkey breast and storage at {dollar}-{dollar}12, 0, 5{dollar}spcirc{dollar}C and 10{dollar}spcirc{dollar}C. The ability of the S. hadar (lux{dollar}sp{lcub}+{rcub}{dollar}) to recover from the treatment was determined by incubating at 22{dollar}spcirc{dollar}C for 10 hrs and monitoring light output. The results showed that metabolic activity was significantly (p {dollar}>{dollar} 0.05) affected by the lactic acid treatment and by storage temperatures of {dollar}-{dollar}12, 0 and 5{dollar}spcirc{dollar}C. The lowest recovery rate was observed after treatment with lactic acid (p {dollar}>{dollar} 0.05) and storage 5{dollar}spcirc{dollar}C.; The implementation of HACCP programs is proposed as a method of reducing foodborne illness. However, good statistical planning and appropriate measurement techniques are required to verify the control of microbial hazards. Key areas in a poultry processing plant were monitored for levels of hygiene by a conventional swab technique and the ATP (adenosine triposphate) bioluminescence assay. A statistical design (i.e., randomized incomplete block) was used and the results showed that the hygiene of the process, including the effect of flocks and day of processing, could be predicted.; The thesis demonstrates that implementation of microbiologically-based systems for validation of HACCP and the introduction of effective carcass decontamination techniques will lead to improve safety and quality of poultry meat. |
