Abstract
Phenolic off-flavour formation in wheat beer systems is influenced by yeast genetics, precursor availability, fermentation temperature, pH, and wort composition. This study examines fermentation control strategies for managing phenolic off-flavour development in wheat beer production. Controlled wheat beer fermentations were conducted using selected yeast strains, temperature profiles, pitching rates, and wort compositions. 4-vinyl guaiacol formation, ferulic acid availability, ester concentration, higher alcohol production, attenuation, pH change, yeast growth, and sensory phenolic intensity were evaluated. The results show that phenolic expression increased when precursor-rich wort was fermented with phenolic-positive yeast under elevated temperature conditions. Moderate temperature control reduced excessive clove-like intensity while preserving typical wheat beer character. High pitching rates reduced growth-driven aroma formation but also lowered flavour complexity. The study demonstrates that phenolic off-flavour control requires coordinated management of yeast strain, precursor release, and fermentation temperature. Proper control supports balanced wheat beer aroma without suppressing desired style identity.