Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/2/2001
Publication Date: 11/1/2001
Citation: CASON JR, J.A., BUHR, R.J., HINTON JR, A. UNHEATED WATER IN THE FIRST TANK OF A THREE-TANK BROILER SCALDER. POULTRY SCIENCE. 2001.
Interpretive Summary: During poultry processing, carcasses are scalded (passed through tanks of hot water) to heat the feather follicles and make it possible to remove the feathers without damaging the skin and meat. Heating the water uses a lot of energy, however, so the process has financial and environmental drawbacks. This study tested whether the temperature of water in the first tank of a multiple-tank scalder can be reduced without compromising the safety and quality of the chickens being processed. When chickens that passed through unheated water in the first tank were compared to carcasses passing through hot water, no differences were found in numbers of aerobic bacteria and E. coli or in the number of carcasses from which salmonella bacteria could be recovered, so there was no indication that food safety was affected. There were no differences in appearance of the carcasses or in the number of feathers that were not removed from the carcasses, and no differences in the tenderness of cooked breast meat from the carcasses, so food quality was not affected. Depending on conditions in individual processing plants, it may be possible for some processors to reduce energy use during scalding without affecting the safety and quality of the carcass.
Technical Abstract: Scalding with unheated water in the first tank of a simulated three-tank scalder was tested to determine whether carcass bacteria, efficiency of feather removal, and cooked breast meat tenderness are affected as compared to carcasses scalded at the same temperature (57 C) in all tanks. This experiment was performed on 3 days using six-week-old broilers. On each day, 8 birds per treatment were processed. During the first 40-s scalding period, one carcass was placed in approximately 24 C water. The other carcass was placed simultaneously in a scalder unit containing approximately 2050 L of water at 57 C. Carcasses were then held out of the water for 15 s after which both were placed for 40 s in opposite ends of the scalder containing water at 57 C. After the second scalding period both carcasses were again removed from the water for 15 sec, followed by another 40 s in the 57 C water. Total scald time was 2 min for each carcass treatment. New York dressed carcasses were rinsed with 200 mL of sterile 0.1% peptone water for 1 min. Aerobic bacteria and E. coli were enumerated and incidence of salmonella was determined by standard methods. After rinsing, carcasses were eviscerated by hand, and chilled for 30 min in ice slush. All carcasses were examined and scored for the presence of feathers, and the appearance and condition of the skin were noted. Four h post- mortem, breast fillets were removed from the carcasses and chilled overnight at 2 C. The next morning, breast fillets were cooked to an internal end-point temperatures of 75-80 C. Warner-Bratzler shear values were measured to determine tenderness. No differences were found in numbers of aerobic bacteria and E. coli, incidence of salmonellae, tenderness of