|KEELARA, SHIVARAMU - North Carolina State University|
|RAVISHANKAR, SADHANA - University Of Arizona|
Submitted to: Institute of Food Technology
Publication Type: Abstract Only
Publication Acceptance Date: 3/18/2016
Publication Date: 7/16/2016
Citation: Green, J.A., Keelara, S.R., Ravishankar, S., Patel, J.R. 2016. Effect of essential oils against E. coli O157:H7 and Salmonella on fresh herbs. Institute of Food Technology. p.04-54. July 16-19, Chicago, IL..
Interpretive Summary: .
Technical Abstract: Consumer awareness of fresh herbs and demand has increased in recent years due to health benefits and distinct aroma in prepared food. There are specific markets for local growers, especially for organically grown herbs. Fresh herbs have been implicated in illnesses associated with Salmonella, E. coli O157:H7 and Cyclospora. Limited treatment options are available in the processing of fresh herbs to prevent the spread of foodborne pathogens. In this study, plant-based essential oils were evaluated on fresh herbs for their antimicrobial properties against Salmonella and E. coli O157:H7. Fresh herbs (Basil, Parsley, Tarragon, Cilantro, and Dill) were inoculated with cocktails of either Salmonella or E.coli O157:H7 and then dip treated with sterile water (control), 50-ppm chlorine, 0.3% and 0.5 % cinnamaldehyde, and 0.1% and 0.3% Carvacrol. Samples were collected on days 0, 2, 7, and 14 for enumeration of survivors during 4°C storage. A treatment with 0.3% carvacrol and 0.5% cinnamaldehyde reduced these pathogens by 4 log CFU/g (P > 0.05%). Bactericidal efficacy of 0.1% carvacrol and 0.3% cinnamaldehyde was superior to chlorine treatment; however, the difference was not significant. Further, the bactericidal effect of these oils varied with herb. E. coli O157:H7 and Salmonella populations were reduced further during storage of treated herbs. There were no visual differences in herbs treated with cinnamaldehyde or 0.1% carvacrol from control samples. Results indicate that 0.5% cinnamaldehyde and 0.1% carvacrol are effective against E. coli O157:H7 and Salmonella, may also retain sensory attributes of fresh herbs, and therefore, may be an alternative wash treatment for organic industry.