Purpose: Assess the effect of combining sodium dodecyl sulfate (SDS) with chlorine (Cl) and peracetic acid (PAA) on antimicrobial activity against Salmonella on chicken skin defeathered following different scalding temperatures.
Methods: Chicken skins were prepared by 1) no scalding and dry hand-defeathering, 2) tap water (20°C) scalding, mechanically defeathering, 3) soft (51°C) scalding, mechanically defeathering, and 4) hard (60°C) scalding, mechanically defeathering. Skin samples (5 cm diameter) from broiler breast skin were inoculated with nalidixic acid resistant strains of Salmonella Typhimurium, Salmonella Enteritidis, and Salmonella Heidelberg as a cocktail. The inoculum was 107 CFU/sample. After 10 min attachment period, skins were treated with antimicrobial solutions of 0.005% Cl, 0.2% PAA, 0.5% SDS, 0.005% Cl with 0.5% SDS, and 0.2% PAA with 0.5% SDS. Positive control was used to determine the real inoculum level. Treated skin samples were rinsed with 10 ml of buffered peptone water (BPW) for 1 min first to remove “loosely attached” cells, and skins were then transferred to fresh BPW and stomached for 1 min to remove “firmly attached” cells. All rinsed and stomached samples were plated on Trypticase soy agar plates with nalidixic acid for bacterial enumeration.
Results: There were no differences in Salmonella attachment to various chicken skins prepared in this study (P>0.05). The results also showed PAA was more effective against Salmonella than Cl, especially on dry defeathered skin. SDS enhanced the efficacy of Cl, but not PAA used in this study.
Significance: Differences in Salmonella attachment to various types of chicken skin could not be demonstrated in this study. Therefore, the impact of SDS could not be assessed effectively.