Edible films containing carvacrol and cinnamaldehyde inactivate <scp><i>Escherichia coli</i></scp> O157:H7 on organic leafy greens in sealed plastic bags

Abstract

Abstract The antimicrobial effects of apple‐, carrot‐, and hibiscus‐based edible films containing carvacrol and cinnamaldehyde against Escherichia coli O157:H7 on organic leafy greens in sealed plastic bags were investigated. Fresh‐cut Romaine and Iceberg lettuce, and mature and baby spinach leaves were inoculated with E. coli O157:H7 and placed into Ziploc® bags. Edible films were then added to the bags, which were stored at 4°C. The evaluation of samples taken at days 0, 3, and 7 showed that on all leafy greens, 3% carvacrol‐containing films had the greatest effect against E. coli O157:H7, reducing the bacterial population by about 5 log CFU/g on day 0. All three types of 3% carvacrol‐containing films reduced E. coli O157:H7 by about 5 log CFU/g at day 0. The 1.5% carvacrol‐containing films reduced E. coli O157:H7 by 1–4 logs CFU/g at day 7. Films with 3% cinnamaldehyde showed reduction of 0.6–3 logs CFU/g on different leafy greens.