Full Length Research Paper

Effectiveness of trisodium phosphate, lactic acid, and acetic acid in reduction of E .coli and microbial load on chicken surfaces

F. M.  Bin Jasass

King Abdulaziz City for Science and Technology, General Directorate of Research Grants, Riyadh 11442, P. O. Box 6086. Kingdom of Saudi Arabia. E-mail: aljasass@kacst.edu.sa. Tel: 966-1-4813373. Fax: 966-1-4813878.

Accepted  6  November, 2007

Procedures for dipping of chicken carcasses in trisodium phosphate (TSP), lactic acid (LA) and acetic acid (AA) were evaluated to determine their effectiveness for reducing E. coli NCTC 10538 and aerobic total counts on the chicken meat surfaces.  Chicken portions were dipped in a suspension of E. coli (7 log CFU/ml) for 20 s and kept for 90 min to allow E. coli to get attached to the chicken surface. The chicken portions were then dipped in 8, 10, and 12% concentration of TSP, 1, 2, and 3% concentration of LA, and 0.5, 1, and 1.5% concentration of AA for 20 s each followed by dipping in tap water for 20 s. A sterile template 4 x 4 cm was placed on the chicken surface and then swabbed by swab cotton. The number of E. coli and aerobic total counts were enumerated. The reduction of E. coli on chicken meat surfaces dipped in 8, 10 and 12% of TSP decreased E. coli by 0.5, 1.2 and 1.6 log CFU/ cm², respectively. The reduction of E. coli on chicken meat surfaces dipped in 1, 2 and 3% LA was 0.5, 1.8 and 2.1 log CFU/cm² respectively. The reduction of E. coli on chicken meat surface dipped in 0.5, 1.0 and 1.5% of AA had decreased the E. coli counts of 0.7, 1.1 and 1.4 log CFU/ cm², respectively. The results showed that LA was more effective against E. coli and aerobic total counts than TSP and AA.

Key words: Trisodium phosphate, Lactic acid, Acetic acid, E. coli, Aerobic count, Quality, Chicken, Poultry.