Effect of caprylic acid alone or in combination with peracetic acid against multidrug-resistant Salmonella Heidelberg on chicken drumsticks in a soft scalding temperature-time setup ¿

Authors: MANJANKATTIL, SHIJINARAJ - University Of Minnesota; NAIR, DIVEK - University Of Minnesota; PEICHEL, CLAIR - University Of Minnesota; NOLL, SALLY - University Of Minnesota; JOHNSON, TIMOTHY - University Of Minnesota; COX, RYAN - University Of Minnesota; Donoghue, Ann - Annie; KOLLANOOR JOHNY, ANUP - University Of Minnesota

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/3/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary: The antimicrobial efficacy of caprylic acid, an 8-carbon fatty acid, against multidrug-resistant Salmonella Heidelberg (MDR SH) on chicken drumsticks under soft scalding conditions was investigated. Chicken drumsticks were spot inoculated with MDR SH and immersed in scalding water containing treatments for 2 min at 54C. The antimicrobial treatments included in the study were 0.5% CA, 1% CA, 0.05% peracetic acid (PAA), 0.5% CA + 0.05% PAA and 1.0% CA + 0.05% PAA. Additionally, the efficacy of the scalding treatments against MDR SH survival on drumsticks for a storage period of 48 h at 4C was determined. Furthermore, the effect of these treatments on the surface color of the drumsticks was also evaluated. Appropriate positive and negative controls were kept for statistical comparisons. The antimicrobial treatments resulted in a significant reduction of MDR SH on drumsticks. For the lower inoculum (~2.5 log10 CFU/g), 0.5% CA, 1% CA, 0.05% PAA, 0.5% CA + 0.05% PAA and 1.0% CA + 0.05% PAA resulted in 0.7-, 1.0-, 2.5-, 1.4- and 1.5- log10 CFU/g reduction of MDR SH on drumsticks, respectively. The same treatments resulted in reduction of MDR SH when the drumsticks were contaminated with a higher inoculum level. Moreover, the antimicrobial treatments inactivated MDR SH in scalding water to undetectable levels, whereas 2.0- to 4.0- log10 CFU/mL MDR SH survived in the positive control. Also, the scalding treatments were effective in inhibiting MDR SH on the drumsticks compared to the respective controls during a storage period of 48 h at 4C, however, the magnitude of reduction remained the same as observed during the scalding treatment. Additionally, none of the treatments affected the color of the drumsticks. Results indicate that CA could be used as an effective natural processing aid against MDR SH on chicken products.

Technical Abstract: The antimicrobial efficacy of caprylic acid, an 8-carbon fatty acid, against multidrug-resistant Salmonella Heidelberg (MDR SH) on chicken drumsticks under soft scalding conditions was investigated. Chicken drumsticks were spot inoculated with MDR SH and immersed in scalding water containing treatments for 2 min at 54C. The antimicrobial treatments included in the study were 0.5% CA, 1% CA, 0.05% peracetic acid (PAA), 0.5% CA + 0.05% PAA and 1.0% CA + 0.05% PAA. Additionally, the efficacy of the scalding treatments against MDR SH survival on drumsticks for a storage period of 48 h at 4C was determined. Furthermore, the effect of these treatments on the surface color of the drumsticks was also evaluated. Appropriate positive and negative controls were kept for statistical comparisons. The antimicrobial treatments resulted in a significant reduction of MDR SH on drumsticks. For the lower inoculum (~2.5 log10 CFU/g), 0.5% CA, 1% CA, 0.05% PAA, 0.5% CA + 0.05% PAA and 1.0% CA + 0.05% PAA resulted in 0.7-, 1.0-, 2.5-, 1.4- and 1.5- log10 CFU/g reduction of MDR SH on drumsticks (P<0.05), respectively. The same treatments resulted in 0.9-, 1.3-, 2.5-, 2.2-, and 2.6- log10 CFU/g reduction of MDR SH when the drumsticks were contaminated with a higher inoculum (~4.5 log10 CFU/g) level (P<0.05). Moreover, the antimicrobial treatments inactivated MDR SH in scalding water to undetectable levels, whereas 2.0- to 4.0- log10 CFU/mL MDR SH survived in the positive control (P<0.05). Also, the scalding treatments were effective in inhibiting MDR SH on the drumsticks compared to the respective controls during a storage period of 48 h at 4C, however, the magnitude of reduction remained the same as observed during the scalding treatment (P<0.05). Additionally, none of the treatments affected the color of the drumsticks (P>0.05). Results indicate that CA could be used as an effective natural processing aid against MDR SH on chicken products.