Effect of Thermal Treatment and Oak Chips on the Volatile Composition of Pedro Ximénez Sweet Wines

Abstract

Young, sweet Pedro Ximénez wines were thermally treated at 65°C for 10, 20, or 30 days to reduce their overall oxidative aging time. Volatile aroma compounds associated with typical aroma descriptors of aged Pedro Ximénez wines were determined by gas chromatography-mass spectrometry. Formation of Maillard reaction products, including furfural derivatives, dihydromaltol, and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, increased during the thermal treatment, while others, such as 2-methoxy-4-vinylphenol, decreased. Wines containing oaks chips had increased concentrations of compounds that contribute to oak and vanilla aromas. Based on these results, thermal treatment of Pedro Ximénez wines may be an effective method to shorten oxidative aging time, thus allowing a possible decrease in production costs.