Impact of ultrasound processing on the nutritional components of fruit and vegetable juices

Fruits and vegetables are rich in vitamins, such as vitamins C and A, as well as in compounds like carotenoids and flavonoids, which have antioxidant properties. They are also a good source of dietary fibers that help promoting digestion and reducing the risk of certain diseases. Accordingly, fruit juices are gaining more room in the market, mainly due to the association of their consumption with healthy habits. However, despite the great benefits of fruit and vegetable juice intake, it deteriorates fast due to both the action of microorganisms and enzymatic action; therefore, it is a challenge to the industry. Thermal treatments can reduce the amount of certain vitamins and antioxidants in juices and affect their flavor and color. Due to the nutritional losses caused by heat, ultrasound has raised the interest of researchers as a likely green alternative to thermal treatments. The impact of US treatment on juices changes depending on the adopted operation conditions, such as exposure time, ultrasonic wave amplitude, treatment temperature, and juices' volume and composition. The aim of the current review is to describe literature findings about the effect of different ultrasound treatments on the nutritional features of fruit and vegetable juice. Ultrasound is a non-thermal technology capable of preserving juices' nutritional quality parameters. However, different trends in the nutritional quality of juices treated were observed and there are few studies assessing ultrasound impact on macronutrients.