This paper reviews the impact of beer-making stages (malting, mashing, boiling, and fermentation) on the behavior of pesticide residues. The large use of pesticides on barley and hop could cause the occurrence of their residues in beer. The foremost factors influencing the stability of residues (pH, temperature, and water content) and the physical-chemical properties of pesticides (octanol-water partition coefficient, vapor pressure, and water solubility) are essential to know their final fate. Most pesticides show a decrease in the unhopped wort because they are adsorbed onto the spent grains after mashing. In addition, their concentrations decrease during boiling and fermentation. Generally, maltsters should dedicate particular attention to the residues of hydrophobic pesticides because they can remain on the malt. Contrarily, brewers should control residues of hydrophilic pesticides because they can be carried over into young beer, disturbing the quality and organoleptic properties (flavor, aroma, taste, or color) of the beer.
Keywords: brewing; plant protection products; quality control; toxicological risk.