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46 WINES&VINES April 2016 OAK BARREL ALTERNATIVES and 22 reclaimed American oak battens) and soaked in model wine (20% alcohol by volume) for seven days at room temperature. The ex- tracts were then analyzed by gas chromatogra- phy-mass spectrometry to determine oak volatile concentrations. Comparable levels of important oak-derived volatiles were observed in reclaimed French oak battens and new French oak as well as reclaimed American oak battens and new American oak (see "Concentration of Volatiles in Toasted Oak" on page 45), although the concentrations of oak volatiles differed between French and American oak battens, in agreement with previous stud- ies. 1,7,8 Reclaimed French oak in particular con- tained higher proportions of the trans-isomer of oak lactone rather than the cis-isomer; whereas reclaimed American oak predominantly con- tained cis-oak lactone. These results demonstrate that reclaimed oak is capable of imparting oak aroma and flavor to wine and is therefore suit- able for use in winemaking. Potential carryover of Brettanomyces spoilage To investigate the potential carryover of Brett- anomyces spoilage, the concentrations of 4-eth- ylphenol and 4-ethylguaiacol were measured in reclaimed oak. No 4-ethylphenol was detected in any of the reclaimed oak samples, and only trace levels of 4-ethylguaiacol (i.e., less than 5.1 μg/g) were observed (see "Concentrations of 4-ethylguaiacol and 4-ethylphenol in Reclaimed Toasted Oak"). These results indicate there was no carryover of Brettanomyces-derived volatile phenols during the barrel reclamation process; however, this may also reflect the absence of spoilage in the first place. A spoilage trial was therefore undertaken to investigate Brettano- myces viability under FIR toasting conditions. The trial involved an untoasted, reclaimed oak batten being soaked in yeast peptone dex- trose (YPD) medium and inoculated with a Brettanomyces culture for four days. The batten was then subjected to FIR toasting, after which shavings were collected and soaked in YPD media for seven days. The resulting media was streaked onto agar plates and incubated for 14 days. Where yeast growth occurred, the ge- nomic DNA was extracted for molecular iden- CONCENTRATION OF 4-ETHYLGUAIACOL AND 4-ETHYLPHENOL IN RECLAIMED TOASTED OAK Oak Samples Concentration (μg/g) 4-ethyl guaiacol 4-ethyl phenol Reclaimed French oak a nd–4.1 nd Reclaimed American oak b nd–5.1 nd nd = not detected a Values are means from 24 replicates. b Values are means from 22 replicates. The barrel reclamation process converts each used barrel into approximately 60 reclaimed oak battens.