Microbiological evaluation of coatings starch-based extracted from tropical fruits during postharvest storage: Microbiological evaluation of edible coatings

Abstract

Starch-based edible coatings, in addition of having organoleptic properties, allows the gas exchange.The aim of this study was to evaluate the microbiological activity of coatings based on starch extracted from banana, mango and soursop fruit, applied to stenospermocarpic ‘Ataulfo’ mango fruit during postharvest storage. 1 cm² segment of tissue from a batch of mango fruit were sectioned, placing them on potato dextrose agar  and incubating them for seven days, making strain selection. A pathogenicity test was carried out by inoculating fruit with 10 µL of a spores suspension at 1x10-⁶ of each of previously isolated strain (eight). These were assigned CP as nomenclature (Pathogenic Strain), selecting and identifying the highly aggressive strain which was  morphologically identified and selected for qualitative and quantitative evaluation damage. An in vivo microbiological evaluation  (CP₃) was made with stenospermocarpic ‘Ataulfo’ mango fruit coated with 2% (w/v) starch. Moderate damage was observed in control fruit and slightly visible damage in coated fruit. Mango coating inhibited the CP₃  strain damage by 66% up to eight days of storage. Starch-based coatings for horticultural product help to reduce  damage caused by microorganisms during postharvest handling.