Methanol a.k.a. wood alcohol is generated from fermenting wood, pectin, skins of fruits, and distillation. There is a simple WHO-approved test to check for dangerous levels of methanol. The various strains of brewer’s yeast aka Saccharomyces cerevisiae that we stock will produce ethanol by fermenting glucose (grape sugar), maltose (grain sugar) and fructose (fruit sugar). Methanol is a toxic byproduct of fermentation, but its levels are so low that unless you distill your homebrew, you should be safe. If you still want to test for methanol levels, please refer to this document.