Physicochemical Characteristics, Antioxidant and Antibacterial Activities of Liquid Smoke Derived from Mixed Sawdust and Cocoa Pod Husks Biomass

Abstract

This study aimed to analyze the physicochemical characteristics, antioxidant and antibacterial activities of liquid smoke derived from mixed sawdust (MS) and cocoa pod husks (CPH) biomass. The liquid smoke formed by pyrolysis of MS and CPH biomass (Theobroma cacao L.) has the physical characteristics of brown color, transparrent, has floating solids, and has an acidic pH of 3.79 for MS and 5.43 for CPH. The results of the antibacterial assay of both liquid smokes by agar diffusion method against 3 pathogenic bacterial isolates; Escherichia coli FNCC 0091, Staphylococcus aureus FNCC 0047 and Salmonella typhimurium FNCC 0150 showed positive results with the formation of clear zones around the test discs. Antioxidant activity assay showed that liquid smoke derived from the biomass of MS had an IC50 value of 0.112 mg/mL, more potential than liquid smoke derived from the biomass of CPH, which was 2.060 mg/mL. Liquid smoke chemical composition analyzed by Gas Chromatography-Mass Spectrometry method showed that liquid smoke derived from MS biomass was dominated by acetic acid (64.64 %), phenols (12.08 %) and acetone (5.78 %), while the liquid smoke derived from CPH biomass was dominated by methylamine (37.26 %), acetic acid (24.61 %) and acetone (19.89 %). The acetic acid, phenols, methylamine and acetone content in both liquid smokes thought to play an important role on its antioxidant activities and inhibition of bacterial growth. HIGHLIGHTS Pyrolysis uses biomass as raw material in the form of mixed sawdust from the home furniture industry and CPH which are a by-product of the chocolate processing industry The liquid smoke obtained from the pyrolysis of both types of biomass has a unique composition and has antibacterial and antioxidant properties The liquid smoke has the potential to be applied as a preservative in food products GRAPHICAL ABSTRACT