Impact of Closure OTR on the Volatile Compound Composition and Oxidation Aroma Intensity of Sauvignon Blanc Wines during and after 10 Years of Bottle Storage

Abstract

The oxygen transfer rate (OTR) of closures is a well-known parameter impacting the quality of Sauvignon blanc wines (SBw) within the first years of storage, but little research has been published on its long-term effects. The chemical changes in oxidation odor intensity in three SBw sealed with natural cork and other closures that had different known OTRs, ranging from <0.1 to 4.6 mg/year, were monitored over a 10 year period. During aging, free SO2 and 3-sulfanylhexanol loss, concomitant with increases in dissolved O2, OD420, and sotolon, were correlated with closure OTR levels. After 10 years of aging, sensory analysis was conducted, supported by additional chemical analysis of aroma impact markers, including methional, phenylacetaldehyde, 2-furanmethanthiol, 4-methyl-4-sulfanylpentan-2-one, ethyl-2-sulfanylacetate, and hydrogen sulfide, as well as total SO2 and dissolved CO2. These analyses revealed that selected SBw were protected from oxidation over a 10 year aging period, provided that the closure OTR did not exceed 0.3 mg/year.

Impact of the Closure Oxygen Transfer Rate on Volatile Compound Composition and Oxidation Aroma Intensity of Merlot and Cabernet Sauvignon Blend: A 10 Year Study

“…No copper fining was carried out. The overall experimental design is presented in Table 1 and corresponds exactly to that described previously by Pons et al 27 Green bottles (750 mL) were obtained from Saint-Gobain Emballage (Cognac, France). Bottles were inverted 1 h after bottling, except for screw caps which were kept upright throughout the experiment.…”

“…Similar results were also obtained for white wines kept under screwcaps and microagglomerates. 27 Moderate or large oxygen ingress through the closure leads to many chemical reactions involving SO 2 loss and modification of aroma compound composition (Table 4). After 10 years of storage, such volatile compounds were detected in a wide concentration range from below their ODT to very high levels (OAV > 1).…”

“…26 The way the closure can modulate the white oxidation/ reduction kinetics has received much attention. 27 Studies investigating the impact of closures on the red wine composition are scarce and most concern only a short period of time, sufficient only to study reductive phenomena. 28 Most authors have studied the evolution of wines at earlier stages of bottle maturation: 5 years for Cabernet Sauvignon 29 or even less than 2 years for aging in Southern Italy red wines 30 and Merlot/Tannat blends.…”

“…32,33 Unfortunately, the impact of stoppers on the longterm aging of red wines has not been widely documented till date. As in a recently published study on white wines, 27 we evaluated the sensory and composition evolution of three red wines from Bordeaux selected for their intrinsic qualities as a function of closure type over a period of 10 years.…”

Cork, a Natural Choice to Wine?

“…However, technological advances allow the creation of novel types of closures, so the ranking related to oxygen permeability of different closures is modified. More recent work by [ 56 ] over a 10-year period examined the chemical alterations in the strength of the oxidation odour in three Sauvignon blanc wines sealed with natural cork and various closures that had varied known oxygen transfer rates. Free SO 2 and 3-sulfanylhexanol loss during ageing were connected with closure oxygen transfer rate levels, as were increases in dissolved O 2 , OD420, and sotolon.…”