Mackenzie Aragon* and Thomas Collins
*WSU, University Dr., Richland, WA, 99354 (mackenzie.aragon@wsu.edu)

Commercial oak barrel alternative products toasted using different methods (vacuum, double toast, convection, fire, and infrared) were analyzed for products of lignin and hemicellulose degradation formed during the toasting process. Oak extracts in model wine (14.5% v/v ethanol) were analyzed using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS SPME-GC-MS). Samples from three separate lots of each product were analyzed for furfural, 5-methyl furfural (5MF), trans-oak lactone, cis-oak lactone, guaiacol, 4-ethyl guaiacol (4EG), 4-methyl guaiacol (4MG), syringol, eugenol, vanillin, trans-isoeugenol, and 4-methyl syringol (4MS). The repeatability coefficient and linear discriminant analysis were used to determine the lot-to-lot variation of each toasting method. In general, variation between lots increased in the medium and medium plus. The method with the least variability varies based on the toast level. Significant differences in volatile composition between products of the same nominal toast levels produced with different methods were found. Understanding how each toasting method varies, and the differences between them, will allow winemakers to have more control over their final product.

Funding Support: Scott Laboratories