Influence Of Ultra-High Pressure Homogenisation On Physicochemical And Sensorial Properties Of Orange Juice In Comparison With Conventional Thermal Processing

The effect of different ultra-high pressure homogenisation (UHPH) treatments on physicochemical and sensorial properties of orange juice was studied in comparison with thermal pasteurisation (90 degrees C, 1 min). UHPH treatments consisted on combinations of two inlet temperatures (10 or 20 degrees C) and three pressures (100, 200 and 300 MPa). Effect of treatments was assessed on general quality parameters (colour, pH, degrees Brix, titratable acidity, reducing sugars and non-enzymatic browning index), particle size distribution and cloud stability. None of the UHPH treatments caused significant differences in the degrees Brix, reducing sugars, pH and non-enzymatic browning index with respect of fresh or pasteurised juice. Only titratable acidity was significantly lower when inlet temperature of UHPH treatments was 20 degrees C. UHPH treatments significantly reduced the particle size and in consequence the cloudiness and the total colour value ( increment E*) increased. The overall consumer acceptability of UHPH and pasteurised juices was similar.