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This study investigated the effect of functional coating using 2% chitosan and different concentrations of olive cake extract (OCE) and orange peel extract (OPE) on the physicochemical quality attributes of cucumber during cold storage at 4 °C for 21 days. Both coating and storage influenced (p ≤ 0.05) the physicochemical attributes of cucumber. The highest values of moisture content, total soluble solids (TSS), pH, total phenolic contents (TPC), DPPH radical scavenging activity, yellowness (b*), and hardness were found in coated samples, which also showed the lowest values of the lightness (L*), greenness (a*), total viable count (TVC), yeast and mold counts, and acidity (p ≤ 0.05). Uncoated cucumber samples showed the highest (p ≤ 0.05) levels of acidity, lightness, greenness, TVC, and yeast and mold count. During storage, concomitant (p ≤ 0.05) reduction in moisture, TSS, pH, TPC, DPPH radical scavenging activity, L*, a*, b*, and hardness along with concurrent (p ≤ 0.05) increment in acidity, TVC, and yeast and mold count were evident in all cucumber samples. Interestingly, the changes in the aforementioned attributes were minimal in functionally coated samples in comparison to uncoated ones, suggesting the potential of OCE and OPE to preserve quality attributes of cucumber during cold storage.

Edible chitosan coatings with natural functional ingredients were used to preserve quality attributes of fresh Barhi date fruit. Fruits were coated with chitosan and/or 1 and 2% olive cake extract (OCE) or orange peel extract (OPE). Both coated and uncoated fruits were stored at 4 °C for 4 weeks. A slight decrease in the pH and increase in acidity with storage was observed. However, when chitosan was mixed with OCE or OPE, an increase in pH was observed with a concomitant decrease in acidity. The phenolic content of the samples was decreased with time. However, coating the date with OCE or OPE significantly (p ≤ 0.05) increased the total phenolic with a concomitant increase in radical scavenging activity. The textural properties, particularly hardness, were better preserved in case of coated dates. The sensory evaluation data showed non-significant changes in the acceptability of the Barhi dates throughout the storage period. Chitosan-coating significantly (p ≤ 0.05) inhibited mold growth over time. Scanning electron microscope (SEM) imaging showed difference among different coatings. According to principal component analysis (PCA), OCE and OPE were found to have protective effects on fruit quality.