Ultrasound and autoclave-deacetylated Achatina fulica shell chitosan: Characterisation and effect on tomato and cucumber fruit qualities during storage.

Chitosan from African giant snail (Achatina fulica) shells derived through autoclave- (SSC) or ultrasound-assisted (SSC) deacetylation was characterised and evaluated for quality and shelf life of tomatoes and cucumbers over 10 days of ambient (26 ± 2 °C) and refrigerated (4 ± 2 °C) storage. A 64.03 and 54.41% deacetylation degrees were achieved for SSC and SSC respectively with the SEM showing uniform surface morphologies. Moisture loss in tomatoes was effectively moderated by SSC and SSC treatments as depicted by higher weight retention (93.65% and 81.80%) compared to untreated samples (58.52%) after 10 days of refrigerated storage. Autoclave-derived chitosan significantly retained colour of tomato and cucumber. Ascorbic acid retentions were 88.76% and 87.34%, and 86.40% and 77.01% for SSC and SSC-treated tomatoes at ambient and refrigerated storage, respectively. Yeast and mould growths were completely inhibited for 10 days of refrigerated storage. Chitosan treatment enhanced quality and shelf life of tomatoes and cucumbers in the order SSC > SSC > control.