Innovative Surface Nano Zinc Oxide Coatings: A Breakthrough in Grape Preservation, Enriching Phytochemicals, and Mitigating Fungal Contamination for Enhanced Nutritional Quality

Abstract

This study explores the transformative impact of the innovative surface nano zinc oxide coatings on grapes, emphasizing their influence on postharvest attributes, phytochemical composition, and fungal population. Distinct coating formulations, including distilled water (Control), chitosan (C), chitosan-nano zinc oxide (C-NZO), and chitosan-nano zinc oxide with the addition of essential oils (C-NZO-EO), were applied to fresh grapes. Results unveiled that the C-NZO-EO treatment positively impacted potassium, calcium, and magnesium levels. Control samples exhibited the highest acidity (3.8), while C-NZO-EO demonstrated superior visual rachis scores (3.41). Anthocyanidin analysis revealed elevated values especially for C-NZO-EO-treated grapes. Fungal populations were significantly reduced in samples treated with C-NZO-EO to reach (3.44 CFU/g). In conclusion, coating with C-NZO-EO emerged as a highly effective strategy for grape preservation, offering enhanced nutritional quality and fungal resistance.