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BACKGROUND: The greatest hurdle to the commercial marketing of fresh-cut fruits is related to their higher susceptibility to enzymatic browning, tissue softening, and microbial growth. The aim of this study was to test the efficacy of a pectin-based edible coating and low oxygen modified atmosphere packaging (MAP) to control enzymatic browning and reduce microbial growth of fresh-cut Rojo Brillante' persimmon. The survival of Escherichia coli, Salmonella enteritidis and Listeria monocytogenes artificially inoculated on fresh-cut fruit was also assessed. The pectin coating was amended with 500 IU mL(-1) nisin (NI) as antimicrobial agent and 10gkg(-1) citric acid and 10gkg(-1) calcium chloride as anti-browning and firming agents, respectively. Persimmon slices were dipped in the coating or in water (control) and packed under 5 kPa O-2 (MAP) or in ambient atmosphere for up to 9 days at 5 degrees C. Microbial growth, package gas composition, colour, firmness, polyphenol oxidase activity, visual quality and overall sensory flavour of persimmon slices were measured during storage. RESULTS: Coating application combined with active MAP significantly reduced the CO2 emission and O-2 consumption in the package. The coating was effective in reducing browning and also inhibited the growth of mesophilic aerobic bacteria. Coating also reduced the populations of E. coli, S. enteritidis and L. monocytogenes. CONCLUSION: The combination of the pectin-based edible coating and active MAP proved to be the most effective treatment to maintain the sensory and microbiological quality of persimmon slices for more than 9 days of storage. (c) 2016 Society of Chemical Industry

The effect of antioxidants controlling enzymatic browning of eggplants was studied in extract and fresh-cut tissue. Initially, the effect of ascorbic acid (AA), citric acid (CA), peracetic acid (PA), calcium chloride, cyclodextrin, cysteine (Cys), hexametaphosphate and 4-hexylresorcinol (Hexyl) at different concentrations was studied in extracts and precipitates of eggplant. Cys and Hexyl were effective at 10 mM in both the extract and pellet. Higher concentrations were needed to have an effective control of enzymatic browning in samples treated with AA (20 mM), CA (50 mM) and PA (50 mM). Next, the application of AA, CA, PA, Cys and Hexyl at different concentrations was studied on fresh-cut eggplant tissues during storage at 5C. Cys was effective as antioxidant, extending the shelf life till 9 days of storage at 5C when applied at a concentration of 1%. Tissue browning increased as AA and Hexyl concentrations increased.

El objetivo de este trabajo fue estudiar el efecto de un recubrimiento comestible y el envasado en atmósferas modificadas (AM) en el control del pardeamiento enzimático de caqui "Rojo brillante". Los trozos de caqui fueron sumergidos en un recubrimiento a base de proteína de soja, ácido cítrico y cloruro de calcio o en agua como control. Posteriormente, las muestras se envasaron en bandejas de polipropileno (PP) y se termosellaron en una atmósfera normal (aire) con un film de PP perforado (AN-P) o sin perforar (AN-SP) o en dos mezclas gaseosas (AM-A: 15 kPa CO2 + 5 kPa O2; AM-B: 50 kPa O2). Las muestras se almacenaron a 5 ºC durante un periodo de 10 días, evaluándose de manera periódica la composición de la atmósfera en el interior del envase, el color (coordenadas CIELAB, L*, a*, b*), firmeza, capacidad antioxidante total y análisis sensorial del caqui troceado. El envasado en la AM-A en combinación con la aplicación del recubrimiento mostró un efecto sinérgico en el control del pardeamiento enzimático, manteniendo la calidad visual del caqui minimamente procesado por encima del limite de comercialización durante todo el periodo de almacenamiento. Sin embargo, se observó una disminución de la capacidad antioxidante total del caqui. La aplicación de elevadas concentraciones de O2 (AM-B) dañó el tejido del fruto dando lugar a un aumento del pardeamiento. La firmeza del caqui troceado no se vio afectada ni por la aplicación del recubrimiento, ni de las AM. La aplicación del recubrimiento mejoró el aspecto del caqui troceado durante el almacenamiento sin afectar negativamente el sabor del mismo.