Effect of chitosan coating and storage time on the sensory and physicochemical quality of minimally processed “Hayward” kiwifruit

Edible coatings represent a promising preservation technology with significant potential to protect food products from microbial contaminants, extend postharvest shelf life, and add value to crops such as kiwifruit. These coatings offer the advantage of direct application to the food surface by dipping, spraying, or brushing, thereby creating a modified atmosphere. Chitosan is an edible coating formulated from naturally derived biodegradable materials, characterized by high antimicrobial activity, biocompatibility, and low toxicity. However, the impact of chitosan on the sensory and physicochemical quality of minimally processed (MP) and stored kiwi remains insufficiently explored. The present study aimed to investigate the effects of different chitosan doses (S0,5%, S1%, and S1,5%) compared to a control on the sensory quality and physicochemical properties of MP kiwifruit. Over an 8-day storage period, a trained panel evaluated sensory attributes (appearance, aroma, flavor, and texture), and physicochemical parameters (titratable acidity [TA], total soluble solids [TSS], RATIO, Vitamin C, and firmness) were monitored. Samples treated with S0.5% and S1% chitosan exhibited the highest stability, showing minimal changes in both sensory and physicochemical profiles. Conversely, the S1.5% dose negatively impacted sensory characteristics—similar to the control—resulting in reduced color uniformity, aroma intensity, and typical flavor. Furthermore, this sample showed a decrease in sweetness and an increase in overripe notes, along with a loss of firmness and Vitamin C. While all chitosan treatments increased TSS and showed a smaller increase in RATIO than the control, TA remained stable at all doses. These results suggest that chitosan doses up to 1% are an effective post-harvest strategy for maintaining the quality and extending the shelf life of MP kiwifruit.