β-Glycosidases enhance wine aroma by releasing volatile aglycones from non-volatile glycosides. Commercial preparations contain primarily pectinases and only display β-glycosidase as a secondary activity which limits their potential. Here, the extremophilic β-glucosidase A from Halothermothix orenii, (BglA) has been compared with Rapidase ® for the production of aromatic wines and in the remediation of smoke-tainted wines. Model systems as well as real juices and wines have been enriched with geranyl glucoside, typical of white varieties, and guaiacyl glucoside, commonly found in red wines exposed to oak and wines made from grapes exposed to smoke. The hydrolytic capacity of BglA was evaluated by measuring the released volatiles in the gas phase with Solid Phase Microextraction and GC-MS. BglA, despite an apparent instability at low pHs, is twice as effective in the release of volatiles in sweeter wines and in grape juices offering an excellent alternative for the early stages of the winemaking process and in the juice industry.

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β‐Glucosidases are used in the food industry to hydrolyse glycosidic bonds in complex sugars, with enzymes sourced from extremophiles better able to tolerate the process conditions. In this work, a novel β‐glycosidase from the acidophilic organism Alicyclobacillus herbarius was cloned and heterologously expressed in Escherichia coli BL21(DE3). AheGH1 was stable over a broad range of pH values (5–11) and temperatures (4–55 °C). The enzyme exhibited excellent tolerance to fructose and good tolerance to glucose, retaining 65 % activity in the presence of 10 % (w/v) glucose. It also tolerated organic solvents, some of which appeared to have a stimulating effect, in particular ethanol with a 1.7‐fold increase in activity at 10 % (v/v). The enzyme was then applied for the cleavage of isoflavone from isoflavone glucosides in an ethanolic extract of soy flour, to produce soy isoflavones, which constitute a valuable food supplement, full conversion was achieved within 15 min at 30 °C.