Decontamination of fresh apples using air micro-nanobubbles with epsilon-poly-lysine

Abstract

Fresh and minimally processed apples demand high-efficiency decontamination approach to ensure their safety and quality. This research investigated air micro-nanobubbles (MNB) assisted washing as an innovative decontamination method for fresh apples, to improve the overall efficiency, a food-grade antimicrobial agent epsilon-poly-lysine (ε-PL) was simultaneously used during the examinations for removing representative pathogen, spoilage yeast, and pesticides from the fruit surface. The findings revealed that the combined ε-PL (250 mg/L) and MNB treatment substantially decreased the microbial load on apple surfaces, achieving beyond 3-log reductions for both Listeria monocytogenes and Pichia kudriavzevii. The pesticide removal rate of trichlorfon by MNB and ε-PL reached 77.3%, significantly (p < 0.05) higher than individual treatments. Additionally, apple quality post-MNB-assisted decontaminations did not show significant differences compared to other treatments after 20 d of storage. MNB-assisted washing with ε-PL is a promising technology for fresh produce decontamination.

Keywords

Epsilon-poly-lysine(ε-PL) / Micro-nanobubbles (MNB) / Apple decontamination / Microbial removal / Trichlorfon

Author contributions

The authors confirm their contribution to the paper as follows: study conception and design: Lu H, Shi Z, Zhang H; data collection: Lu H, Tan S, Wang J, Shi Z; analysis and interpretation of results: Lu H, Shi Z, Zhang H; draft manuscript preparation: Lu H, Shi Z; editing and manuscript revision: Lu H, Tan J, Zhang H, Shi Z. All authors reviewed the results and approved the final version of the manuscript.

Data availability

The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.

Acknowledgments

Authors acknowledge the support of the CAU-Cornell Dualdegree Program. The authors also appreciate the support from the 2115 Talent Development Program of China Agricultural University.

Conflict of interest

The authors declare that they have no conflict of interest.

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