Effect of poly-ε-lysine incorporated into alginate-based edible coatings on microbial and physicochemical properties of fresh-cut kiwifruit

This work investigates the effectiveness of different concentrations (0.05%, 0.10% and 0.15%) of poly-epsilon-lysine (epsilon-PL) incorporated into an alginate-based edible coating to inhibit microbial proliferation and maintain physicochemical properties of fresh-cut kiwifruit stored at 4 +/- 0.5 degrees C for 14 d. Changes in O-2 and CO2 concentration, physicochemical indices, microbiological counts and morphological properties were measured. Results showed that low levels of e-PL (0.05% and 0.10%) led to lower CO2 and higher O-2 concentrations inside the packages compared with samples with control and 0.15% epsilon-PL treatments. Moreover, the alginate-based edible coating containing 0.05% epsilon-PL significantly reduced electrolyte leakage and MDA content while maintained the green color, total chlorophylls content, ascorbic acid, antioxidant capacity and morphological properties of fresh-cut kiwifruit. In addition, 0.05% epsilon-PL treatment reduced aerobic plate counts and yeast and mould counts by 3.5 and 2.5 log CFU/g, respectively, at the end of evaluation. Our results show that there is promise for the use of edible coating incorporated with epsilon-PL to preserve the quality of sliced kiwifruit.