Innovative Approaches to Quince Juice Clarification: Efficiency of Casein, Chitosan, and Xanthan Gum Under Ultrasound Treatment

This is the first comprehensive study that investigates quince juice clarification using novel protein–polysaccharide fining agents (casein [CA], chitosan [CH], xanthan gum [XG]) and their combinations with optimized dose, temperature, and time conditions, compared against the conventional gelatin (GE) + kieselsol (KS) + bentonite (BE) combination, while also quantifying the discrete contribution of ultrasound to process performance and storage stability. Single‐agent applications reduced turbidity but did not reach commercial clarity. By contrast, the full‐dose current combination (0.50 g/L CA + 0.10 g/L XG + 0.75 g/L CH, 40°C) achieved 2.68 Nephelometric Turbidity Unit (NTU) at 210 min, whereas the conventional combination (0.05 g/L GE + 0.75 g/L KS + 0.75 g/L BE, 40°C) reached 2.38 NTU at 120 min. Ultrasound‐assisted clarification (45 kHz, 5 min) initially increased turbidity due to cavitation but ultimately decreased to 6.79 NTU at 210 min, which was the lowest value. To further evaluate product quality and stability, clarified quince juices were characterized for compositional attributes (pH, titratable acidity, total soluble solids, and color), antioxidant properties (total phenolic compound, 2,2‐diphenyl‐1‐picrylhydrazyl [DPPH], 2,2‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid diammonium salt [ABTS + ], Ferric Reducing Antioxidant Power [FRAP]), and storage stability over 6 months at 4°C, including turbidity, browning index (BI), whiteness index, heat–cold stability, and pH value. Clarified samples consistently demonstrated superior performance relative to cloudy control, with lower turbidity and BI, higher whiteness stability, and more stable pH profiles throughout storage. Overall, the findings confirm that optimized combinations of current fining agents provide an effective alternative to conventional clarification, offering both scientific and industrial insights into clarifier selection, product quality, and long‐term shelf life of clarified fruit juices.