Microbial inactivations with hydrolysed lactoferrin and other natural antimicrobials in fresh-cut fennel

•Different natural antimicrobials were studied on fresh-cut fennel.•Enterobacteriaceae was the most sensitive microbial group to studied sanitizers.•Psychrophiles was the most resistant microbial group to studied sanitizers.•Hydrolysed lactoferrin showed the highest psychrophilic reduction (2.5 log units).

Natural antimicrobials (nisin, lactoferrin, thymol and citrus extract) were studied as sustainable alternatives to conventionally used NaOCl in fresh-cut (FC) fennel. Enterobacteriaceae was the most sensitive microbial group to studied sanitizers according to δ values, while psychrophiles were the most resistant. Based on inactivation modelling and sensory scores, nisin (N-250; 0.250 g L−1), lactoferrin (L-50; 50 g L−1), together with hydrolysed L-50 (LFH), were selected and studied comparing to water-washed (CTRL) and NaOCl (150 mg NaOCl L−1) on FC fennel. LFH achieved the highest psychrophilic reduction of 2.5 log units. Although NaOCl achieved the highest mesophilic, Enterobacteriaceae, lactobacilli and yeasts and moulds reductions of 1.7, 1.0, <1.7 and 1.6, respectively, N-250 still achieved 0.50-1.0 log unit reductions compared to CTRL. Conclusively, LFH and N-250 are natural antimicrobial treatments with good microbial inactivation rates which may be a good alternative to conventional NaOCl used by the FC industry.