Functional Quality Improvement of Subpar Citrus Juice Using Microfluidization

Granulated citrus has shriveled juice sacs with less flowable juice that significantly decreases their acceptability. Moreover, the juice tends to be low in nutritional and functional quality. This study was designed to examine the impact of microfluidization on the biochemical and functional qualities of citrus juice extracted from granulated “Dancy” tangerine. The extracted juice was processed at five different pressures (6000, 9000, 12,000, 15,000, and 18,000 psi) for three different passes (1, 2, and 3). The effect of microfluidization on soluble solid content, titratable acidity, total and reducing sugars, flavonoid content, antioxidant activity, and total phenolic content (TPC), and ascorbic acid content were evaluated. Results showed that TPC was significantly (p < 0.05) enhanced by more than 50% in juice processed through 18,000 psi with three passes compared to the control. Flavonoids, antioxidant activity, and soluble solid content also increased significantly as pressure and pass number increased. TPC, total flavonoids and total antioxidant potential showed a strong positive correlation. Heat map grouped microfluidized samples into four clusters based on their common quality attributes. This study demonstrated that microfluidization could serve as an effective method for enhancing the biochemical properties of juice extracted from partially granulated citrus, which is typically considered of lower quality.