A Comprehensive Study on Osmotic Dehydration and Edible Coatings with Bioactive Compounds for Improving the Storage Stability of Fresh Berries

Abstract

Berries are highly perishable due to their high water content, making them prone to rapid deterioration and spoilage. This study investigates the effects of osmotic dehydration and edible coatings, with and without bioactive compounds, on various quality attributes of blueberries, raspberries, and strawberries during storage. The berries were pretreated using osmotic dehydration with apple juice, followed by the application of edible coatings from Chlorella vulgaris protein, with or without the addition of aqueous rosemary extract as a source of bioactive compounds. The results indicated that the combination of the two methods significantly reduced weight loss in all berry types, with the incorporation of bioactive compounds further enhancing moisture retention up to approximately 3% for blueberries and raspberries and 5% for strawberries. Total phenolic content and antioxidant activity exhibited significantly increased stability in coated samples, with bioactive coatings contributing to improved antioxidant properties. The HPLC analysis proved that the bioactive profile was preserved after the treatments. Microbial analysis demonstrated that edible coatings, particularly those enriched with bioactive compounds, effectively inhibited microbial growth (TC approximately 4.5 log(CFU/g) with limit = 5 log(CFU/g) and YM approximately 3.5 log(CFU/g) with limit 4 log(CFU/g)), thereby extending the shelf life of the berries. These findings suggest that the synergistic application of osmotic dehydration and edible coatings, especially those containing bioactive compounds, significantly enhances the quality, shelf life, and potential health benefits of fresh berries during storage.