Background. Turbidity is an important quality parameter of fruit juices. Sedimentation of pulp particles suspended in juice may result in a negative assessment of the product’s quality by consumers. Therefore, turbidity stabilization is a challenge for juice producers. In this study, two types of homogenization were used to constrain juice sedimentation. Cloudy juice made of the „Grandarosa” cv. strawberries was used for the research. High-pressure homogenization was carried out with an Atomo 3.0 homogenizer at a pressure of 200 and 600 bar. Ultrasonic homogenization was carried out with a Sonics VCX 750 sonicator using 750W power for 2 and 8 minutes. The juice samples were analyzed for particle size distribution, viscosity, turbidity, total anthocyanin content, phenolic compounds and ascorbic acid content.
Results and conclusions. In the case of ultrasonic homogenization, approximately 70 % of the particles present in the juice had a diameter below 25 µm, while in non-homogenized juice, the fraction of particles with a diameter below 25 µm was only 25 %. High-pressure homogenization, regardless of the pressure used, had a higher efficiency in the fragmentation of turbidity particles than ultrasonic homogenization (approximately 90% of the particles below 25 µm in size). Homogenization at a pressure of 200 bar resulted in the highest increase in viscosity to 6.5 mPa·s, by 135 % more than the non-homogenized juice. The juice homogenized ultrasonically for 8 minutes had the highest turbidity level, with a turbidity of 2¹¹0 NTU. The average content of total anthocyanins (6 mg/100 cm³) and L-ascorbic acid (16.8 mg/100 cm³) in the strawberry juice did not differ statistically significantly, regardless of the type of homogenization. High-pressure homogenization and ultrasonic homogenization are highly effective in reducing the size of particles in strawberry juice, however, none of them significantly degrades the anthocyanins and ascorbic acid content.