MIRABELA IOANA LUPU, CARMEN LILIANA BADARAU, VASILE PADUREANU, CRISTINA MARIA CANJA EFFECTS OF THERMAL AND ULTRASOUND TREATMENTS ON L ASCORBIC ACID OF GRAPES JUICE Improving the nutritional quality for non-alcoholic beverages (especially the content of valuable natural antioxidants) by using modern ultrasound treatments represent a challenge for more and more food scientists. The objective of this research work was to estimate the effect of some ultrasound treatments on the total L ascorbic acid content and on several physicochemical characteristics of grape juice stored for different time periods. In order to determine this influence, the sonication parameters chosen were the amplitude (60%, 80%) and the treatment times (18, 36 min.). The samples treated by direct sonication (amplitude 80%, 36 min.) and stored 17 days had higher values of total L ascorbic acid content.
Keywords: L ascorbic acid, grapes juice, ultrasound treatments