Hop bitterness in beer evaluated by computational analysis

Abstract

Beer flavour and aroma are greatly influenced by the hop(s) employed in the brewing process. The iso-α-acids post wort boiling are the major compounds responsible for bitterness, which are detected by the bitter taste receptors (TAS2Rs) in oral taste buds. This family of receptors is activated in the presence of bitter molecules, which send chemical signals to the brain, making it possible to differentiate whether the detected molecules have a pleasant taste (or not). It is of interest to predict the behaviour of hop compounds towards bitter receptors such that the bitterness of different hop varieties can be predicted based on quantitative analysis of composition. Computational simulation, based in high-performance computing (HPC), allow the simulation of interactions of molecules with the various TAS2Rs, enabling the prediction the bitterness of these hop compounds. These techniques, will soon enable the design of beverages with customised flavours, greatly reducing the need for experimental evaluation. In this work, α and β-acids, iso-α-acids, and prenylflavonoids are analysed against the bitter receptors TAS2R10, TAS2R14 and TAS2R46.  Using computational blind docking and molecular dynamics, xanthohumol was identified to have the highest bitter profile.