Evaluation of postharvest calcium treatment and biopreservation with Lactobacillus rhamnosus GG on the quality of fresh‐cut ‘Conference’ pears

Abstract

BACKGROUND

Biological preservation with probiotic bacteria has arisen as an alternative to control the growth of foodborne pathogens on food. The objective of this work was to evaluate the effect of postharvest calcium application and biopreservation with Lactobacillus rhamnosus GG on the quality and bioaccessibility of total phenolic content and antioxidant activity in fresh‐cut pears. RESULTS

The immersion of whole pears in a calcium chloride solution did not provide added value. Despite the increase in observed activity of PME and PPO enzymes in fresh‐cut pears during storage, the browning index and firmness values were constant for all samples. The antioxidant properties, including antioxidant activity, total phenolic content and vitamin C content, were maintained during storage, but a significant decrease was observed after in vitro simulated digestion. Ca/LGG samples showed the lowest calcium content (1.75 ± 0.00 g kg−1) after 9 d of storage at 4 °C. In general, the overall visual quality scores were higher in fresh‐cut pears treated with L. rhamnosus GG than in non‐treated pears, with the highest values in the NoCa/LGG (7.7 ± 0.2) samples after 9 d at 4 °C. CONCLUSION

Fresh‐cut pears with a postharvest treatment of calcium and immersed in a solution containing antioxidant agents and probiotic bacteria could be a suitable alternative to dairy products for maintaining the overall quality of fruit for up to 9 d of storage.

The authors thank the Spanish Ministry of Science and Innovation (AGL‐2012‐2038 671). This work has been supported by the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement (AGAUR fellowship 2017‐FI‐B200164 to Lorena Zudaire and 2015‐FI‐B100156 to M. Belén Iglesias) and the CERCA Programme of Generalitat de Catalunya. L. Plaza thanks the National Institute for Agronomic Research (INIA) for a DOC‐INIA research contract. I. Aguiló‐Aguayo thanks the National Programme for the Promotion of Talent and Its Employability of the ‘Ministerio de Economía, Industria y Competitividad’ of the Spanish Government and the European Social Fund for her Postdoctoral Senior Grant ‘Ramon y Cajal’ (RYC‐2016‐2019 949). The researchers also thank Daniel Martín, Silvia Villaró and Jordi Sabata for their technical support.