Facile Determination of Antioxidant Activity of Coconut Liquor Using Cyclic Voltammetry

Abstract

In the aspect of sustainable food quality evaluation, reducing the cost and material consumption associated with testing, increasing the efficiency of processing, and reducing the overall environmental footprint are essential considerations. Lambanog coconut liquor is a popular distilled spirit in the Philippines, which is sold by producers in diverse quality and compositions. Despite the popularity of coconut vodka, there are few reports on physicochemical properties and antioxidant activity in the literature. This study evaluates the physicochemical and antioxidant activity of this distilled spirit obtained from the Cavite and Laguna provinces in the Philippines. The antioxidant activity determination is carried out using cyclic voltammetry and reported in milligrams equivalent to ascorbic acid (AA). This process is simple and fast, does not require complicated preparation techniques, and no toxic solvents are needed for the evaluation of antioxidant activity. The antioxidant activity evaluated from the anodic curve shows the ascorbic acid equivalents for different brands and found to be 532.0 mg AA, 425.3 mg AA, 381.4 mg AA, 563.2 mg AA, and 284.2 mg AA for Brands A to E. Two brands are acidic, and two are basic. Brand D has the highest range of conductivities (419.9 to 734.4 µS/cm), while Brand E has the lowest (111.4 to 135.4 µS/cm). Future research will explore the chemical constituents present that affect the physicochemical properties of the distilled spirit.