Characterization of Aroma Components by HPLC-DAD and HS-SPME/GC-MS of Whortleberry and Bilberry Fruits (Vaccinium arctostaphylos L. and Vaccinium myrtillus L.)

Abstract

In this study; aroma components, some biochemical properties (sugar amount (HPLC-DAD), vitamin C amount, water-soluble solids amount) and antioxidant capacities (bioactive component contents and antioxidant capacity amounts) of V. arctostaphylos and V. myrtillus fruits were determined. Methanol extraction was applied to the fruit samples, which were made homogeneous after being shredded. Aroma (volatile) components were determined by HS-SPME/GC-MS (Headspace-Solid Phase Micro Extraction) technique combined with Gas Chromatography-Mass Spectrometry. Total antioxidant activity (TAC), total phenolic substance amounts (TPC) and total flavonoid substance amounts (TFC), which are among the bioactive component contents, were examined. As antioxidant capacity, the amount of free radical scavenging (DPPH and ABTS) activity and the amount of ferric (III) ion reducing antioxidant power (FRAP) capacity were determined. As a result of the analyses, 27 and 33 aroma compounds were determined in V. arctostaphylos and V. myrtillus fruits, respectively. The main components found among the aroma compounds are alpha-terpineol (22.67%), (E)-2-hexenal (17.63%), and linalool (9.78%). in the V. arctostaphylos fruit. V. myrtillus fruits were determined to contain menthol (22.93%), alpha-eudesmol (11.50%), and germacrene D (8.33%). In addition, the chemical classes of aroma compounds identified were monoterpenoid, aldehyde, hydrocarbon, alcohol, ester, sesquiterpene, and sesquiterpenoid classes in V. arctostaphylos and V. myrtillus fruits. Moreover, the total sugar amount in V. arctostaphylos fruits was found to be 11.30%, and the total sugar amount in V. myrtillus fruits was 13.94%. The amount of vitamin C in V. arctostaphylos fruits was detected as 33.26 mg/kg, and the amount of vitamin C in V. myrtillus fruits was contained as 44.17 mg/kg. The amount of water-soluble solids in V. arctostaphylos and V. myrtillus fruits was determined to be 12.13% and 13.43%, respectively. The amounts of total sugar, vitamin C and water-soluble solids in V. myrtillus fruits were higher than the amounts in V. arctostaphylos fruits. According to the antioxidant results, the TAC, TPC, DPPH, ABTS and FRAP values of the methanol extract obtained from V. myrtillus fruits, excluding TFC, demonstrated higher antioxidant features than the values attained from V. arctostaphylos fruits.