Effects of Pressure and Pass Number During High-Pressure Homogenization on the Physical Stability and Quality of Cloudy Hawthorn Juice

Cloudy hawthorn juice contains pectin and a polydisperse pulp phase that readily separates during storage. This study examined how high-pressure homogenization (HPH) pressure and pass number affected its physical stability and quality. Juice was treated at 30–150 MPa for one to five passes. Data were analyzed using mixed-effects models for repeated sedimentation measurements and appropriate multiple comparisons for treatment comparisons. The apparent DLS Z-average decreased from approximately 4.5 µm in the untreated juice to 2.0–2.6 µm after one pass and 0.65–0.90 µm after five passes. After 7 d at 4 °C, the sedimentation index was 43% in the control and 71–83% after one pass. At 30 MPa, increasing the treatment from one to two–five passes raised the day-7 index from about 71% to 83–88%, an additional gain of 12–17 percentage points. Total flavonoid content was 25.97 mg RE/100 mL in the control, 22.73–25.50 mg RE/100 mL after one pass, and 18.18–19.84 mg RE/100 mL after four or five passes. DPPH activity remained within 64.98–67.56% (control, 66.95%), whereas ABTS activity was 55.64–58.20% (control, 55.37%). Among the one- to three-pass treatments evaluated sensorially, 90 MPa for one pass showed the most favorable mean sensory profile. Under the laboratory conditions tested, a moderate single-pass treatment offered a better quality–stability balance than repeated homogenization; it should be regarded as a preliminary quality-oriented condition rather than a validated preservation process.