Pot Ale as a Sustainable Raw Material for the Generation of Biopolymers

Pot ale is a high-volume co-product of whiskey distillation with potential for valorisation. However, its composition varies depending on production processes and source, which may limit its consistent reuse. This study characterised pot ale from three Irish distilleries, analysing total protein, ash content, colour (Lab*), and FTIR spectra. Significant differences were found between sources, particularly in protein and ash levels. Discriminant analysis showed clear grouping by distillery. Biopolymer films produced using the same pot ale samples showed variation in colour and surface properties, while mechanical properties remained comparable across samples. These results highlight that pot ale composition is variable and that this diversity must be accounted for in efforts to develop consistent processing or formulation strategies.