Ultrasonic treatment utilization during strawberry juice processing

Abstract

Berry fruits are a rich source of various nutrients, while their products also represent a nutritionally valuable source. Technological processes are developing in the direction of minimal processing techniques, avoiding intensive heat treatments and use of chemical additives. Use of non-invasive treatments such as ultrasounds shows a number of advantages, from increased bioactive compounds content to a significantly shortened time. The aim of study was to determine the effect of different processing methods (thermal and ultrasonic treatment) on the physicochemical properties, specialized metabolites and antioxidant activity of strawberry juice. The highest dry matter content and electrical conductivity was determined in thermal treated juices, while ultrasonic treatment positively affected on the total acids content and total soluble solids. Ultrasonic treated juices had even 51 % higher vitamin C content, 23 % higher total anthocyanin content and also significantly higher antioxidant capacity compared to the thermal treated samples.

Keywords

• ultrasonic treatment
• thermal treatment
• specialized metabolites
• antioxidant capacity
• strawberry juice