Influence of Antimicrobial Compounds and Modified Atmosphere Packaging on Radiation Sensitivity of Listeria monocytogenes Present in Ready-to-Use Carrots (Daucus carota)

Abstract

Radiosensitization of Listeria monocytogenes was determined in the presence of trans-cinnamaldehyde, Spanish oregano, winter savory, and Chinese cinnamon on peeled minicarrots packed under air or under a modified atmosphere (60% O2, 30% CO2, and 10% N2). Samples were inoculated with L. monocytogenes HPB 2812 serovar 1/2a (106 CFU/g) and were coated separately with each active compound (0.5%, wt/wt) before being packaged under air or the modified atmosphere and irradiated at doses from 0.07 to 2.4 kGy. Results indicated that the bacterium was more resistant to irradiation under air in the absence of active compound. The dose required to reduce L. monocytogenes population by 1 log CFU (D10) was 0.36 kGy for samples packed under air and 0.17 kGy for those packed under the modified atmosphere. The active compounds evaluated in this study had an effect on the radiation sensitivity of L. monocytogenes on carrots. The most efficient compound was trans-cinnamaldehyde, where a mean 3.8-fold increase in relative radiation sensitivity was observed for both atmospheres compared with the control. The addition of winter savory and Chinese cinnamon produced a similar increase in relative radiation sensitivity but only when samples where packed under modified atmosphere conditions.

Scientific Opinion on the efficacy and microbiological safety of irradiation of food

“…On various types of lettuce and leafy greens, D 10 values for E. coli O157 ranged from 0.3 to 0.45 kGy (Niemira, 2008) and from 0.15 to 0.20 kGy (Mahmoud, 2010;Trigo et al, 2009). Similar D 10 values were found for L. monocytogenes and Salmonella on peeled minicarrots, minimally processed cucumbers and sprouted seeds (Caillet et al, 2006b;Dhokane et al, 2006;Saroj et al, 2006). On arugula minimally processed salads, D 10 values for Salmonella were in the range between 0.15 and 0.2 kGy and those for L. monocytogenes were between 0.3 and 0.5 kGy (Nunes et al, 2008).…”

Effect of Antimicrobial Coatings on the Radiosensitization of Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes in Fresh Broccoli

“…Hydroxyl groups in cellulose are replaced by methoxyl groups after etherification, resulting in a significant decrease of hydrogen bonding that was responsible for the crystallinity of cellulose (8). Research has been conducted on the use of essential oils (EOs) from spices combined with c-irradiation to increase the radiosensitization of pathogenic bacteria such as E. coli, Salmonella Typhi, and Listeria monocytogenes in carrots (3,4). However, these studies did include an evaluation of EOs in mixtures with other antimicrobial compounds.…”

Reduction of Listeria monocytogenes contamination on produce – A quantitative analysis of common liquid fresh produce wash compounds

“…1011, 1123, 1137, 1158 serve as surrogates in the absence of data for L. monocytogenes) , (Allende et al, 2007;Bari, Nakuama, et al, 2005;Bari, Ukuku, et al, 2005;Bialka & Demirci, 2008;Caillet, Millette, Turgis, Salamieri, & Lacroix, 2006;Critzer, Kelly-Wintenberg, South, & Golden, 2007;Dhokane, Hajare, Shashidhar, Sharma, & Bandekar, 2006;Fan, Niemira, & Prakash., 2008;Fan, Sokorai, Sommers, Niemira, & Mattheis, 2005;Kim et al, 2006;Leverentz et al, 2003;Leverentz, Conway, Janisiewicz, & Camp, 2004;Mahmoud, Bachman, & Linton, 2010;Niemira, 2003;Niemira, 2005;Randazzo, Pitino, Scif o, & Caggia, 2009;Schuenzel & Harrison, 2002;Trias, Badosa, Montesinos, & Bañeras, 2008;Waje et al, 2009;Yaun, Sumner, Eifert, & Marcy, 2004;Young Lee et al, 2006). Liquid fresh produce wash or rinse compounds (henceforth simply referred to as 'produce washes') with chemical compounds such as chlorine or chlorine dioxide are the traditional methods of reducing microbial populations on produce, and have therefore received the most attention to date (Parish et al, 2003).…”