DETERMINATION OF TOTAL PHENOLIC AND FLAVONOID CONTENTS, ANTIOXIDANT ACTIVITY AND B VITAMINS OF DIFFERENT IRANIAN NON-ALCOHOLIC BEERS
Abstract
This paper seeks to evaluate the quantity of B1, B2 and B6 vitamins using HPLC method and investigate the amount of total phenolic content (TPC), total flavonoid content (TFC) and DPPH radical scavenging activity (antioxidant activity), pH, Brix and color of Iranian non-alcoholic beers. For doing so, four bottles of non-alcoholic beer (named from A to D) purchased from Iranian markets were investigated over a three-month storage period. Results demonstrated that after the storage time, TPC, TFC and antioxidant activity of all the samples reduced noticeably. Sample B had the highest level of total phenolic content, which was 10.17 mg of GAE/mL, but it had the lowest antioxidant activity showing the higher responsibility of the type of phenolic compounds in antioxidant activity than their quantity. Moreover, the results of HPLC method, conducted in the third month, showed that sample B had the highest level of vitamin B1 and B6, which were 68.47 and 43.11 mg/kg, respectively. In addition, vitamin B1 had the highest amounts in both samples. According to the results, it can be said that Iranian non-alcoholic beers contain a significant amount of total phenolic, flavonoid compounds with high antioxidant activity and B vitamins.