Winemaking
In the most notable expression of Nebbiolo, the wines of Barolo, there is division between what is considered a "traditional" approach to Nebbiolo and a "modernist" approach. The roots of both style can trace its history to the early "pre-technology" production of Nebbiolo. Prior to the advent of temperature control fermentation, the late harvest dates for Nebbiolo meant that the wines began fermentation when the weather turned cold. These cool temperatures would delay fermentation for several days, extending the maceration period and extraction of phenolic compounds such as tannins. When fermentation did begin, temperatures would reach excessive levels of 95-100 °F (35-38 °C) which would drastically reduce potential aromas and flavors. With the high levels of tannins, these early Barolos would require five years or more aging in oak barrels to soften some of the astringency. Lack of understanding of proper hygiene lead to less sanitary condition than what both traditional and modernist producers maintain today. Those conditions lead to the development of bacterial infection of cement fermentation tanks and old wood barrels that contributed to the development of off flavors and potential wine faults that would require at least 24 hours decanting to alleviate.
Today's winemaking for both traditionalist and modernist include strict hygiene controls and the use of some modern winemaking equipment. Rather than fall into one hardline camp or the other, many producers take a middle ground approach that utilizes some modernist technique along with traditional winemaking. In general, the traditional approach to Nebbiolo involves long maceration periods of 20 to 30 days and the use of older large botti size barrels. The modern approach to Nebbiolo utilizes shorter maceration periods of 7 to 10 days and cooler fermentation temperatures between 82 and 86 °F (28 and 30 °C) that preserve fruit flavors and aromas. Towards the end of the fermentation period, the cellars are often heated to encourage the start of malolactic fermentation which softens some of Nebbiolo's harsh acidity. Modern winemakers tend to favor smaller barrels of new oak that need only a couple years to soften the tannic grip of the wines. While new oak imparts notes of vanilla, it has the potential to cover up the characteristic rose notes of Nebbiolo.
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