Finding MeOH: A literature review on methods for the determination of methanol in Lambanog and alcoholic beverages

Lambanog is a popular traditional alcoholic beverage in the Philippines. It plays an important role in special festivities and events, particularly in rural communities. Lambanog is a transparent white liquor made from fermented coconut flower sap. While lambanog has been consumed for many generations, the lambanog industry has failed to take off and compete in both domestic and international markets. Recent methanol (MeOH) adulteration issues have been a severe setback for the industry. The industry is also concerned about the lack of good and standardized production processes in micro, small, and medium enterprises (MSMEs). Because quality and safety issues are inherent elements of product definition, the lack of methods for MSMEs to define, validate, and test their lambanog makes it exceedingly difficult for the industry to become competitive. Due to the prevalence of methanol poisoning around the world, particularly in the Philippines, where there is unregistered and bootleg lambanog manufacture, this study was created to review existing methods for the determination of methanol. This includes colorimetric, spectroscopic, chromatographic, biochemical, electrochemical, assay-based, refractometer-based, and novel methods of detection of MeOH. This review aims to identify the most effective method for MeOH determination that can be translated into a paper-based device that can be potentially used by MSMEs in the country.