Improving the shelf-life and functionality of an orange juice by the addition of polyphenol-enriched extracts obtained using natural deep eutectic solvents

This study aimed to develop novel orange juices formulated with different NADES extracts derived from orange by-products. E-nose and e-tongue analyses were used to determine the optimal concentration of each extract (15 %) for beverage formulation. The formulated juices were characterized in terms of color, pH, and phenolic profile. A shelf-life study was conducted to monitor microbiological spoilage, volatile profile, and color changes over thirteen days of storage at two temperatures (4 °C and 8 °C). Additionally, a challenge test was performed using Saccharomyces cerevisiae and Lactiplantibacillus plantarum as spoilage microorganisms. The innovative juices showed a varying phenolic content depending on the extract used, ranging from 70 to 132 µg/mL, with hesperidin being the most abundant compound. Yeasts were the predominant microflora during storage, with control samples exceeding 5.0 log CFU/mL after just 9 days, regardless of storage temperature. In contrast, the samples containing extract exceeded this threshold only after 13 days at 8 °C. Challenge test results showed that the formulated juices effectively reduced the growth kinetics of Saccharomyces cerevisiae, regardless of storage temperature. Limonene was the dominant volatile compound across all juice samples. The extract-enriched juices exhibited higher levels of terpenoids (mainly β-linalool) and certain aldehydes (hexanal and 2-E-hexenal) than the controls, maintaining a more stable volatile profile throughout storage. Overall, this study demonstrates the feasibility of extending the shelf life and enhancing the functionality of orange juice using NADES extracts and without compromising its organoleptic properties.