Trans-cinnamaldehyde nanoemulsion wash inactivates Salmonella Enteritidis on shelled eggs without affecting egg color or embryo growth

Authors: ALLEM, J - University Of Connecticut; BALASUBRAMANIAN, B - University Of Connecticut; RANKIN, K - University Of Connecticut; SHAH, T - University Of Connecticut; Donoghue, Ann - Annie; UPADHYAYA, I - University Of Connecticut; SARTINI, B - University Of Rhode Island; LUO, Y - University Of Connecticut; UPADHYAY, A - University Of Connecticut

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/17/2023
Publication Date: 2/15/2023
Citation: Allem, J., Balasubramanian, B., Rankin, K., Shah, T., Donoghue, A.M., Upadhyaya, I., Sartini, B., Luo, Y., Upadhyay, A. 2023. Trans-cinnamaldehyde nanoemulsion wash inactivates Salmonella Enteritidis on shelled eggs without affecting egg color or embryo growth. Poultry Science. 102(4). Article 102523. https://doi.org/10.1016/j.psj.2023.102523.
DOI: https://doi.org/10.1016/j.psj.2023.102523

Interpretive Summary: Salmonella is a major foodborne pathogen that causes enteric illnesses in humans, primarily through the consumption of contaminated poultry meat and eggs. Despite implementation of traditional disinfection approaches to reduce contamination, egg-borne outbreaks continue to occur, raising public health concerns and adversely affecting the popularity and profitability for the poultry industry. The present study investigated the efficacy of a plant based phytochemical Trans-cinnamaldehyde (derived from cinnamon bark), in nanoemulsions. Nanoemulsions are prepared with emulsifiers to make oil based substances more absorbable. In addition, the efficacy of nanoemulsions treatments in reducing the ability of Salmonella to cross the egg shell barrier was investigated. Nanoemulsions were effective in inactivating Salnonella. Nanoemulsion wash also inhibited trans-shell migration of Salmonella. Results suggest that these treatments could potentially be used as an antimicrobial wash to reduce Salmonella on eggs.

Technical Abstract: Salmonella Enteritidis is a major foodborne pathogen that causes enteric illnesses in humans, primarily through the consumption of contaminated poultry meat and eggs. Despite implementation of traditional disinfection approaches to reduce S. Enteritidis contamination, egg-borne outbreaks continue to occur, raising public health concerns and adversely affecting the popularity and profitability for the poultry industry. The present study investigated the efficacy of Trans-cinnamaldehyde nanoemulsions (TCNE) prepared with emulsifiers Tween 80 (Tw.80) or Gum Arabic and lecithin (GAL) as dip treatments, at 34°C, for reducing S. Enteritidis on shelled eggs in presence or absence of 5% chicken litter. In addition, the efficacy of TCNE dip treatments in reducing trans-shell migration of S. Enteritidis across shell barrier was investigated. The effect of wash treatments on shell color were evaluated on days 0, 1, 7 and 14 of refrigerated storage. Moreover, nanoemulsion treatments were examined for their influence on embryonic development. TCNE-Tw.80 or GAL treatments (0.06, 0.12, 0.24, 0.48%) were effective in inactivating S. Enteritidis by at least 2 to 2.5 log cfu/egg as early as 1 min of washing time (P<0.05). In presence of organic matter, nanoemulsions (0.48%) reduced S. Enteritidis counts by ~ 2 to 2.5 log cfu/egg as early as 1 min, (P<0.05). Nanoemulsion wash also inhibited trans-shell migration of S. Enteritidis, as compared to control (P<0.05). The nanoemulsion wash treatments did not affect shell color (P>0.05) and did not influence the growth of embryos incubated for 18 days (P>0.05). Results suggest that TCNE could potentially be used as an antimicrobial wash to reduce S. Enteritidis on shelled eggs, although further studies investigating the effect of TCNE wash treatments on organoleptic properties of eggs are necessary.