Global market is flooded with vitamin-enriched foods, mainly beverages. Major vitamins for enriching beverages are the antioxidant vitamins A, C and E. Ascorbic acid is readily oxidized and lost during storage of the beverages, at rates depending on the conditions of storage. This fact is of great importance for the consumer who must know how to store beverages and when to consume them in order to get the maximum benefit of added vitamin C. The objective of this paper was to determine the amount of ascorbic acid lost in beverages applying different preservation methods and storage condition. Beverage was made in laboratory conditions with synthetic L-ascorbic acid added according to the national legislations. After 30 days of storage at 4-8oC ascorbic acid overall loss was from 81.01% to 90.27% in thermally pasteurized samples and from 97.83 % to almost complete loss in samples preserved with sodium benzoate.