Barrels aging/storage

In barrel-aged red, white, and model wines, naturally occurring furfuryl alcohol decreased in concentration with time. In red wine, furfuryl ethyl ether was identified as a degradation product after 55 wk of storage. The average percentage decrease of furfuryl alcohol was 73% (Spillman et al, 1998). 

In the traditional, quality-orientated European vineyards, the drawn-off wine was collected in small wooden barrels. The wooden fermentors were not hermetic enough to protect wine from contact with air. Concrete and stainless steel tanks have been recommended since their development, for wine storage during the completion phase of fermentation. This completion phase precedes barrel aging. The tanks must of course be completely full and perfectly airtight. 

These measures are good manufacturing practices of winemaking, irrespective of the risk of phenolic taint. The main preventive measures should be performed during wine storage, aging (mainly in oak barrels) and bottling. As the release of precursors... 

The wine used in this experiment was a 1998 Monastrell red wine from Bodegas San Isidro in Jumilla, Murcia. Table I shows the analytical data of the wine prior to wood aging. All the barrels were filled with the same wine. A control wine was kept in a stainless steel tank. The wines were matured in the oak barrels for six months and stored during one year in the bottle, to meet the specifications for crianza wines. Wine samples were taken after three and six months of oak aging and after one year of bottle storage. Duplicate samples were taken from each barrel. 

Sotolon (3-hydroxy-4,5-dimethyl-2(5H)-furanone) concentration in Poit correlates positively with years of barrel storage aging. Within certain limits Sotolon concentration can also correlate with the intensity of typical aroma descriptors nutty , spicy and the perceived age of barrel stored Port wine. This phenomenon can be demonstrated even with Sotolon additions to unaged base port. 

In conclusion, sulfur dioxide permits the storage of many types of wine known, today that would not exist without its protection. In particular, it permits extended barrel maturation and bottle aging. In view of its involvement in a wide variety of chemical reactions, it is not easy to determine the optimum dose to obtain all the benefits of SO2 without any of its unfortunate side-effects. The adjustment should be made within plus or minus 10 mg/1. 

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