Use of an eco-friendly preservation technology as a strategy to increase the microbiological shelf-life of a novel ready-to-eat salad containing vegetable by-products

PEREZ, PABLO; FERNANDEZ MARÍA VERÓNICA; JAGUS, R. J.; AGUERO, MARIA VICTORIA

Journal of Food Process Engineering

John Wiley and Sons Inc

Año: 2024 vol. 47

The objective of this investigation was to evaluate different UV-C irradiation doses ina novel ready-to-eat vegetable product containing vegetable by-products (red beetleaves) and determine the microbiological shelf-life and quality indicators duringrefrigerated storage (5 ± 1C). During processing, no chemical disinfection was carried out and after the packaging step, 3 doses of UV-C irradiation were applied(CTRL: 0 kJ/m2, L: 1 kJ/m2, M: 4 kJ/m2, and H: 7 kJ/m2) on the vegetable productstudied (50% Creola purple lettuce, 25% beet leaves, and 25% arugula). It wasobserved that the intermediate dose (M) was the most suitable treatment since itcould increase in six times its microbiological shelf-life. Additionally, M was the onethat showed the lowest loss of total polyphenols and the one that best maintainedthe antioxidant capacity (DPPH), probably attributed to the decrease in the activityof deterioration enzyme, PPO and higher ascorbic acid content at day 4. When evaluating % CO2/O2 on headspace of bags, UV-C treatments reached earlier the dynamicequilibrium. Finally, all UV-C irradiation treatments were successful against the simulated contamination. In that way, significant reductions of L. innocua and E. coli werefound, with differences from up to 2 log cycles during storage. Finally, it can be concluded that UV-C treatment can increase the microbiological shelf-life of the novelready-to-eat vegetable product, with quality indicators stabilization.Practical applicationsReady-to-eat salads present a short shelf-life, which hinders their commercialization.As preservation technologies are required, UV-C irradiation is an eco-friendly alternative for its preservation as it has the potential to replace traditional disinfection treatments by reducing the water footprint of the total process. Therefore, since theUV-C treatment is applied in the last step of the process (after packaging the product), microbiological contamination occurring in this type of vegetable products during processing is minimized. However, additional investigation is necessary to assessits suitability for a novel ready-to-eat salad containing horticultural by-products.