Volatile Compound Changes in Beer Pasteurization: a Comparative Study of Different Beer Styles Using SPME–GC–MS and Chemometrics

Pasteurization may alter beer flavor and aroma, as heat treatment can diminish freshness. Previous studies reported only minor effects, but focused exclusively on lightly hopped beers. Here, we investigated the influence of pasteurization on the volatile fraction of six craft beer styles, including hop‐forward ones, using SPME–GC–MS and chemometric tools. PCA confirmed subtle overall changes, while PLS‐DA identified 22 key volatiles—mainly esters and hop‐derived compounds—driving differences between pasteurized and unpasteurized samples. Pasteurized beers showed higher levels of unbranched ethyl esters, whereas unpasteurized beers were enriched in branched esters and hop‐derived volatiles such as myrcene, linalool, citronellol, geraniol, and methyl geranate, all characterized by low odor thresholds and high sensory relevance. These findings provide new insights into how pasteurization impacts volatile composition, particularly in hop‐rich beers, with direct implications for beer freshness and sensory quality.