Institution: Alabama Agricultural and Mechanical University
Principal Investigator: Armitra Jackson-Davis, Ph.D.
Alabama Agricultural and Mechanical University
Department of Food and Animal Sciences
4900 Meridian Drive
Normal, AL 35762
Pathogens, such as Salmonella enterica and Campylobacter jejuni, on raw meat and poultry products are a major food safety concern to regulatory agencies, meat processors and consumers. Antimicrobial use during processing can provide significant reductions of pathogen numbers, but poultry skin is hydrophobic (due to its fat content) and can resist thorough wetting by commonly used water-based antimicrobials. This likely limits the effectiveness of the microbial treatment.
Development of a food grade acid/saponin sanitizer with GRAS chemicals for broiler carcasses would be attractive to the poultry industry because of the following attributes: chemical stability, convenience of use, free of detectable organoleptic properties at use levels, environmental safety and biodegradable. Saponins are produced by certain plants and have detergent surfactant characteristics that can facilitate efficient wetting of fatty surfaces such as poultry skin. Some saponins, such as those in extracts from Yucca schidigera, have FDA GRAS status and are approved for use as ingredients in foods and beverages. Although studies have been published on the effect of organic acid/surfactants on the inactivation of E. coli, the “multiple-hurdle” effect of organic acid/saponin on Salmonella and Campylobacter has not been evaluated on broiler skin. The long-term goal of this research project was to enhance poultry meat safety by developing approaches for cleaning deep skin pathogen contamination in poultry carcasses or parts.
The objective of the project was to evaluate the antibacterial efficacy of organic acid solutions alone or combined with selected saponins against Salmonella and Campylobacter in a laboratory broth medium and to then determine the antibacterial effectiveness of selected organic acid /saponin immersion treatments against pathogens and indigenous microflora on chicken skin. The antibacterial effectiveness of lactic/citric acid mixtures (1.5% and 2.5%) or acetic acid (1.0% and 2.0%), alone or combined with Yucca extract (YEX), was evaluated against a 5-strain mixture of Campylobacter jejuni and Salmonella enterica in laboratory medium and on raw chicken skin. Lactic/citric (2.5%), or 2.0 % acetic acid with added 0.5% YEX, exhibited the largest reduction in populations of Campylobacter jejuni and Salmonella enterica in vitro as well as on chicken skin (p < 0.05). The addition of YEX (0.5%) to Lactic/citric acid (2.5%) or to acetic acid (2.0%) can enhance the antibacterial activity of those organic acids against Campylobacter jejuni and Salmonella enterica on raw chicken skin. These results indicate that saponins may have a practical use in combination with organic acids for the reduction of pathogen contamination during processing.
