Innovative Layer-by-Layer Edible Biopolymer Coatings to Optimize Storage Performance and Maintain Postharvest Quality of ‘Barhi’ Dates

‘Barhi’ dates (Phoenix dactylifera L.) are highly prized and widely consumed at the khalal stage, but they are only available for a short time, which highlights the importance of extending their storage life. This study examined the effectiveness of edible coatings in delaying ripening and maintaining fruit quality during cold storage (2 °C). The treatments tested were gelatin alone or gelatin combined with chitosan, Aloe vera gel (AVG), or gum arabic, and applied in a layer-by-layer (LbL) approach. A fifth treatment consisting of deionized water was used as a reference untreated control. The fruit parameters measured included weight loss, decay, moisture content, ripening (rutab transformation), firmness, color (lightness and hue angle), total soluble solids (TSS), titratable acidity (TA), TSS/TA ratio, total sugars, total polyphenols, and enzymatic activity. Results indicated that the LbL edible coating was more effective in preserving postharvest quality. Regarding weight loss and decay rate, the results showed that the control treatment consistently had 1.5–5-fold higher deterioration indicators than the coated fruits. Among the tested treatments, the gum arabic and gelatin coating was the most effective compared to the untreated control, reducing weight loss by over 40%, lowering decay by approximately 80%, and maintaining significantly higher moisture content throughout storage. Concerning carotenoid levels, the untreated fruits exhibited approximately 1.2–1.4-fold higher carotenoid content than the coated fruits. Fruits treated with gum arabic and gelatin exhibited the best preservation effect Sby limiting TSS increase and maintaining higher TA compared with the control. This treatment best maintained antioxidant capacity and phenolic content while significantly suppressing the activities of polyphenol oxidase and peroxidase. Overall, the LbL coating strategy successfully maintained the quality of ’Barhi’ dates by mitigating oxidative and enzymatic degradation throughout storage. Principal component analysis and hierarchical cluster analysis demonstrated that treatments gum arabic and gelatin exhibited superior effectiveness in extending the date storage life in terms of physicochemical properties and antioxidant activity, followed by chitosan and gelatin, and Aloe vera and gelatin, compared to the control fruits over a 60-day storage period.