Comparative proximate and phenolic characterization of winemaking sediments

The wine industry generates a wide range of solid residues throughout vinification, many of which remain underexploited despite their potential as sources of bioactive compounds. While byproducts such as pomace and conventional lees have been widely studied, less attention has been given to specific sediment fractions collected at defined stages of the process.In particular, sediments recovered after fermentation and prior to bottling represent a distinct and poorly characterised matrix. Unlike primary lees or pomace, these materials result from prolonged settling and transformation processes, potentially leading to unique compositional profiles shaped by fermentation dynamics, microbial activity, and chemical ageing.These sediments are expected to concentrate structural nutrients (e.g. proteins, fibres, minerals) alongside a diverse range of polyphenols, including phenolic acids, flavonoids, and stilbenes, compounds associated with antioxidant and health-promoting properties. However, their nutritional composition and phenolic signature remain largely unexplored, limiting their integration into valorisation strategies.