Beer is one of the most popular drinks in the world. Based on natural products, quality control to guarantee a product of consistent taste, colour, and composition can be challenging. Amino acids analysis can be used to ensure consistency in the quality of the end-product, and also as an indicator for counterfeiting of branded products. In this article we present a rapid and reliable high performance liquid chromatography–mass spectrometry (HPLC–MS) method to determine amino acids in beer.