School of Food Science and Technology, Chung-Ang University, 72-1 Nae-Ri, Daeduck-Myun, Ansung, Kyungggido 456-756, Republic of Korea.
Poult Sci. 2014 Jan;93(1):208-15. doi: 10.3382/ps.2013-03536.
This study was conducted to evaluate the efficacy of sodium hypochlorite (NaOCl, 0-200 mg/kg), thiamine dilauryl sulfate (TDS, 1,000 mg/kg), and ultrasound (37 kHz, 380 W) on reducing Salmonella Typhimurim, mesophilic aerobic bacteria (MAB), and coliforms on chicken skin. Chemical and physical treatments were applied for 5 min either singly or jointly, and Salmonella previously inoculated on chicken skin were quantitatively assessed using brilliant green agar, and the populations of MAB and coliforms in the native flora were enumerated using plate count agar and violet red bile agar, respectively. In the evaluation of bacterial attachment/detachment, chicken skin was quantitatively assessed for loosely, intermediately, and tightly attached bacteria. The treatment effects on bacteria detachment were also visualized using field emission scanning electron microscopy. In addition, color and textural properties of the skin after treatments were evaluated using a color difference meter and texture analyzer. Antimicrobial activity of NaOCl increased as the NaOCl concentration was increased, especially for loosely attached cells. The combination of 200 mg/kg NaOCl and ultrasound (NaOCl/ultrasound) significant reduced loosely, intermediately, and tightly attached bacteria populations by 0.75 to 0.47, 0.43 to 0.41, and 0.83 to 0.54 log cfu/g for MAB, coliforms, and Salmonella Typhimurium, respectively. However, the combination of NaOCl and TDS (NaOCl/TDS) did not sufficiently reduce those cells on chicken skins, except for loosely attached MAB and coliforms. The NaOCl/ultrasound combination produced a higher reduction in numbers of inoculated and native bacteria flora than any single application, with no negative effect on skin color or texture. Generally, the loosely attached bacteria were less resistant to the chemical and physical treatments than the intermediately and tightly attached bacteria in chicken skin, presumably due to their location in deeper skin layer and crevices. Further research is needed to investigate how the intermediately and tightly attached microorganisms can be effectively eliminated from chicken skin.
本研究旨在评估次氯酸钠（NaOCl，0-200mg/kg）、硫酸月桂酰精氨酸（TDS，1000mg/kg）和超声（37kHz，380W）对减少鸡皮中肠炎沙门氏菌、嗜温需氧菌（MAB）和大肠菌群的效果。化学和物理处理分别单独或联合应用 5min，使用煌绿琼脂定量评估先前接种在鸡皮上的肠炎沙门氏菌，使用平板计数琼脂和紫红胆盐琼脂分别对原生菌群中的 MAB 和大肠菌群进行计数。在评估细菌附着/脱附时，对鸡皮进行定量评估，以确定松散附着、中等附着和紧密附着的细菌。还使用场发射扫描电子显微镜观察了处理对细菌脱附的影响。此外，使用色差仪和质构分析仪评估了处理后皮肤的颜色和质地特性。随着 NaOCl 浓度的增加，NaOCl 的抗菌活性增加，特别是对松散附着的细胞。200mg/kg NaOCl 与超声（NaOCl/超声）联合使用，可使 MAB、大肠菌群和肠炎沙门氏菌的松散附着、中等附着和紧密附着细菌分别减少 0.75-0.47、0.43-0.41 和 0.83-0.54log cfu/g。然而，NaOCl 和 TDS 的组合（NaOCl/TDS）并不能充分减少鸡皮上的这些细胞，除了松散附着的 MAB 和大肠菌群。NaOCl/超声联合处理比任何单一处理都能更有效地减少接种和原生细菌菌群的数量，且对皮肤颜色和质地没有负面影响。一般来说，与鸡皮中的中等和紧密附着细菌相比，松散附着的细菌对化学和物理处理的抵抗力较低，这可能是由于它们位于皮肤深层和缝隙中。需要进一步研究如何有效地从鸡皮中消除中等和紧密附着的微生物。
