One thing we get asked for quite often is a wine that hasn’t been oaked in any way. Of course, we also get asked for wine that has been oaked, but Oak has many influences on the wine and can be used at many stages in the wine making process. Below is a basic summary of the most common uses of oak in wine; this should help you understand the process a bit better. You never know, it may inspire you to dip your toe in the water again (so to speak). Enjoy!
Fermentation and Oak
The most cost effective way of adding an oak flavour to a wine, is by fermenting the still wine in a stainless steel vessel and adding oak chips or staves to the fermenting liquid. This method was popular with the first new world wines exported to the UK in the mid to late 1980’s, chief amongst which was Australian Chardonnay. Using this method imparts oak flavours and aromas (vanilla and toast), that were often overbearing and totally unbalanced with the other varietal characteristics of the finished wine. This damaged Chardonnay’s reputation as a mass market white wine, the sentiment which is still strongly felt today – and unfairly so.
The best method is to ferment the wine in an oak barrel. This is much more expensive and often reserved for smaller production or more prestigious wines; The reason is that its harder to control the temperature of the fermenting liquid, ensuring the yeast ferments the sugars effectively. Wide spread in the old world wine making countries and prevalent now in the new world, the oak flavours and aromas are much more integrated with the rest of the wine. Often these wines are fairly rich in flavour and body due to the process of lees stirring: during fermentation, the active and dead yeast cells are stirred up in the wine.
Barrel fermented Sauvignon Blanc is a great place to start if you want to explore this – try Blind River Sauvignon Blanc to begin with. 10% of the wine in the final blend is fermented in barrel so you get a hint of the richness without too much overt flavour.
For something a bit more punchy, and – admittedly – pricey, Cloudy Bay Te Koko is pretty much the apex of this style. Aged, oaked Sauvignon Blanc and quite incredibly delicious.
Oak and Ageing
Wine regions around the world age their wines in oak before bottling them for sale. Depending upon the region and quality of the vintage these wines will be ready to drink or will develop in the bottle for years to come.
The two most famous regions for oak usage are Bordeaux in France and Rioja in Spain. When ripening black grapes in the northern hemisphere further away from the equator, the grapes Phenolic Ripeness (a measure of skin ripeness) is not as high as in countries such as Australia with a warmer climate. If thick skinned varieties, the skins will be very dry or Tannic. Tannin, along with acidity and potential alcohol facilitate ageing in a wine
In certain areas of Bordeaux, where Cabernet Sauvignon is the lead grape in the blend, wine will be very dry and tannic in its youth. Aged in Oak (which adds more tannin and flavours and aromas of cedar) these wines are destined for ageing in bottle sometimes for decades; during which time the tannins soften, varietal aromas and flavours develop and the wine becomes generally more approachable.
Tempranillo, which is the lead grape in Spain, is also very responsive to oak ageing. Rioja producers or Bodegas use American Oak which imparts numerous flavours and aromas including vanilla and spice, giving Rioja its distinctive flavour. Oak and bottle ageing occur in the Bodega and has legally binding minimum periods attached to different terminology.
Crianza wines are those from fairly ordinary vintages, that won’t age well. Subsequently these are oak and bottle aged for a minimum of 18 months prior to release; These are best drunk young. Reserva wines are made from grapes in better harvests, these will be oak aged for at least 36 months prior to release. Where a Crianza will have primary flavours of strawberry and subtle spice from oaking, Reservas have more secondary aromas and flavours including, vanilla spice, balsamic notes and leather.
The best Riojas and subsequently the most expensive are Gran Reservas. These wines will be aged for at least five years prior to release. These are from the best harvests and will age gracefully in the bottle sometimes for twenty or more years.