Naturally occurring methanol is produced as a byproduct during the fermentation of fruits containing high levels of pectin, meaning that fruit-based spirits and liquors—such as brandy, grappa, calvados, plum brandies (slivovitz), and certain artisanal unrectified fruit moonshines—contain significantly higher concentrations of methanol and other congeners compared to grain-based spirits like vodka, gin, or pure commercial beers.