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Recent advances in biotechnology ensure that brewer's spent grain, the major by-product of the brewing industry, is no longer regarded as a waste but rather a rich source of bioactive compounds. With a hypothesis that the antioxidant constituents of this vegetable waste could be efficiently extracted and valorized, this comparative study assessed the capability of different solvents to extract bioactive compounds and evaluate their antioxidant, antimicrobial and antimutagenic activities. From the twelve tested, the highest concentrations in phenolics (97.83–114.23 mg GAE/100 g DW) were obtained for the methanolic extracts and the aqueous mixtures of ethanol and acetone (60/40 and 40/60, v/v). These data were strengthened by the HPLC-ESI-MS phenolic profile and also by the radical scavenging activities determined by DPPH and ABTS assays. All investigated extracts exert antimicrobial activity against different strains, but the extracts with low phenolic content and low antioxidant activity manifested similar or higher antimicrobial activity (especially towards Candida albicans) and significantly enhanced antimutagenic activity. The results emphasize the importance of selecting the proper extraction solvent in order to obtain extracts rich in biomolecules with specific bioactivities (antioxidant, antimicrobial and/or antimutagenic).

The aim of this work was to find differences in the volatile and phenolic profiles of the traditional Romanian apple brandy pălinca aged with various species of wood chips. Seven types of wood species, two types of oak (Quercus petraea and Quercus robur), plus sweet chestnut, mulberry, walnut, fir and cherry, were considered. The majority of volatile compounds characterizing the aroma profile of pălinca were esters, particularly ethyl esters, with ethyl isobutyrate, ethyl isovalerate, ethyl caproate, ethyl octanoate and ethyl decanoate as the most abundant. The most important source of catechin was cherry wood. Rutin and juglone were solubilised only in walnut wood aged brandy. Vanillin, increased significantly in chestnut aged apple brandy. Given the cost and difficulty in handling wooden barrels, and as an alternative being able to select from a range of specific wooden chips, this work could potentially guide actors in beverage industry to less expensive alternatives.

Brewers' spent grain (BSG) is the insoluble residue generated from the production of wort in the brewing industry. This plant-derived by-product is known to contain significant amounts of valuable components, which remain unexploited in the brewing processes. Therefore, it is essential to develop a more detailed characterization of BSG in order to highlight its potential in developing new value-added products and simultaneously solve the environmental problems related to its discharge. The content of BSG in several biologically active compounds (fatty acids, polyphenols, flavonoids, antioxidant capacity) as well as its volatile fingerprint were assessed and compared with the composition of barley, malt and wheat flour samples. The obtained results emphasized the importance and the opportunities of the re-use of this agro-industrial by-product.