Submitted to: Meeting Abstract
Publication Type: Abstract only
Publication Acceptance Date: 3/15/2013
Publication Date: 7/28/2013
Citation: Abdulmalik, T., Levy, J., Boyer, R.R., Gurtler, J., O'Keefe, S.F., Williams, R.C. 2013. Inactivation of Listeria Monocytogenes and Salmonella Typhimurium in apple juice using combinations of cinnamaldehyde, eugenol and trans-2-hexenal. Meeting Abstract. IAFP Annual Meeting, Charlotte, NC., July 28-31, 2013.,Volume 1, Page 1. Interpretive Summary:
Technical Abstract: Plant-derived essential oil compounds, within the past decade, have gained attention as effective antimicrobials. Some essential oils possess antimicrobial properties effective against foodborne pathogens; however, their use within the food industry is limited by negative organoleptic effects and limited solubility. Using these essential oils in combination with other antimicrobials, naturally occurring within foods, may result in lower effective concentrations. The purpose of this study was to evaluate the antimicrobial activity of two plant essential oil compounds (trans-cinnamaldehyde and eugenol) alone and in combination with trans-2-hexenal (a naturally-occurring apple flavorant) to inactivate Salmonella Typhimurium and Listeria monocytogenes in commercially-processed apple juice. Apple juice samples containing 0.025, 0.050, 0.075 and 0.125% of each individual compound or dual-combinations containing 0.025% of each test compound were inoculated with 7-8 log CFU/ml of S.Typhimurium or L. monocytogenes and stored at 4 or 25 deg C. Bacterial counts were determined after 0, 1, 3, and 7 days of storage on tryptic soy agar. Treatments with 0.050% of trans-cinnamaldehyde, eugenol or trans-2-hexenal, alone, resulted in 5 log CFU/ml reductions of both pathogens within one day at both temperatures. The only exception was trans-2-hexenal, which reduced L. monocytogenes by 4 log CFU/ml after one day at 4 deg C. Both antimicrobial combinations (viz., 0.025% trans-2-hexenal combined with either 0.025% eugenol or 0.025% trans-cinnamaldehyde), however, resulted in greater than 7 log CFU/ml inactivation of S. Typhimurium and L. monocytogenes, following one day at 25 deg C. Both treatments were less effective at 4 deg C, with only 4-5 log CFU/ml inactivation of both pathogens. Adding combinations of trans-2-hexenal with trans-cinnamaldehyde and eugenol to apple juice resulted in at least a 5 log reduction in populations of S. Typhimurium and L. monocytogenes when held at 25 deg C.