Chitosan-citric acid edible coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava

Int J Biol Macromol. 2020 Nov 15:163:1127-1135. doi: 10.1016/j.ijbiomac.2020.07.067. Epub 2020 Jul 9.

Abstract

This study aimed to verify the action of edible chitosan-citric acid (CHI-CA) coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava. Chitosan was obtained from Litopenaeus vannamei shells using high temperature and short exposure times. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of CHI-CA against C. gloeosporioides were determined by macrodilutions at 28 °C/120 h in the absence/presence of CHI-CA (0-10 mg/mL). Scanning electron microscopy was used to evaluate morphological changes in the fungus. Guava slices were coated with CHI-CA (MIC) or 5 mg/mL glycerol (control). Rot incidence and physicochemical, physical, and microbiological factors were determined at 0, 3, 7, and 14 days at 24 °C and 4 °C. Chitosan presented typical structural characterization, 64% deacetylation, and a molecular weight of 1.6 × 104 g/mol. CHI-CA exhibited MIC and MFC values of 5 mg/mL and 10 mg/mL, respectively, and promoted changes in the morphology and cell surface of fungal spores. The fresh-cut guava coated with CHI-CA maintained quality parameters during storage and preserved their sensorial characteristics. Therefore, the use of CHI-CA as a coating is a promising strategy for improving postharvest quality of fresh-cut fruits.

Keywords: Anthracnose; Biopolymer; Minimally processed fruit; Sensory attributes.

MeSH terms

  • Biocompatible Materials / chemistry*
  • Biocompatible Materials / pharmacology
  • Chitosan / chemistry*
  • Citric Acid / chemistry*
  • Coated Materials, Biocompatible / chemistry*
  • Colletotrichum / drug effects*
  • Colletotrichum / ultrastructure
  • Food Preservation*
  • Food Quality
  • Fruit
  • Magnetic Resonance Spectroscopy
  • Psidium
  • Spores, Fungal / drug effects
  • Spores, Fungal / ultrastructure

Substances

  • Biocompatible Materials
  • Coated Materials, Biocompatible
  • Citric Acid
  • Chitosan

Supplementary concepts

  • Colletotrichum gloeosporioides