Antimicrobial activity of safflower seed meal extract and its application as an antimicrobial agent for the inactivation of Listeria monocytogenes inoculated on fresh lettuce

- Results with safflower seed meal extract (SSME) showed antimicrobial activity.
- SSME can be used as an antimicrobial agent for fresh produce.
- Lettuce samples were treated by a combination of SSME and fumaric acid (FA).
- A combined treatment of SSME and FA was effective in inactivating pathogens.

This study examined the antimicrobial activity of safflower seed meal extract (SSME) against foodborne pathogens, and the microbial reduction effects of combined treatment with SSME and fumaric acid (FA) against Listeria monocytogenes inoculated on lettuce. Results with SSME showed antimicrobial activity against the pathogens, with the highest activity against L. monocytogenes. With 0.7% SSME treatment for 3 min, the reduction levels of total aerobic bacteria and L. monocytogenes in lettuce were 1.55 and 1.58 log CFU/g, respectively, compared with the control. In particular, the combined treatment with SSME and FA reduced the populations further by 1.14 and 1.66 log CFU/g compared to those in SSME treatment alone. The combined treatment did not affect quality indicators such as lettuce color. These results indicate that combined treatment of SSME and FA can be used as a novel antimicrobial agent for inactivating the pathogens in fresh produce.

FA: Fumaric acid; SSME: Safflower seed meal extract; Combined treatment: 0.5% FA + 0.7% SSME. Combined treatment of SSME and FA can be used to inactivate the pathogens in fresh lettuce.153