3.3. Quantification of AA in fruit beverages and vitamin C tablets
The validated HPLC and UPLC methods were applied to different fruit juices and vitamin supplements. The content of vitamin C in tested products is reported in Table 3. DHAA was not present in any sample (the results obtained for samples prepared with and without DTT were not statistically different). The results obtained using HPLC and UPLC methods were very similar although, for some products, the results obtained using UPLC were slightly higher than those obtained by HPLC. It may be due to the higher sensitivity of UPLC than HPLC.