Three oak alternatives
Oak barrels were probably developed by the Iron Age communities in northern Europe, most notably the Celts (Iron Age of the British Isles was from about 800 BC to the Roman invasion of 43 AD).Both benefits may be successfully mimicked with the use of oak chips, barrel inserts or inner staves together with micro-oxygenation.
The most common barrel size in use in this country is the 225-litre barrique, usually made from French oak that has been split and air-dried. Larger barrels, such as 500-litre puncheons, are finding favour because the oak flavour tends to be subtler. Thousand-litre fuders or even larger vats (a vat is a permanent vessel, often with an open top) are also becoming popular.
Oak barrels can add flavour and also allow a small amount of air into the vessel, which allows the wine to mature or develop. Both benefits may be successfully mimicked with the use of oak chips, barrel inserts or inner staves together with micro-oxygenation. Purists might argue that barrels do it better but they cannot argue with the economics.
“No one admits to using oak chips,” explained a winemaker who doesn’t use them and prefers to remain anonymous, “but I am sure that many wine producers do,” he added. Oak chips are exactly that, small finger-joint-sized pieces of oak that can be suspended in a tank of wine to impart oak flavour at a cost of a few cents per bottle.
The problem with oak chips is that they contain quite a lot of air, with the risk of oxidation. They are best added during fermentation when the chance of oxidation is small.
Another, also anonymous winemaker, once told me that it is unlikely that an oaky chardonnay, on sale at a profitable price, has not used oak chips or inner staves, although it may also have spent some time in older oak barrels (and therefore qualifies for “aged in French oak barrels” on its back label).
Also known as nunchucks, these are pieces of oak that can be inserted into a barrel to add a new or concentrated oak flavour during fermentation or maturation. They can be inserted by removing the barrel head and attaching them to the inside of a used barrel, or by connecting a string of oak pieces to a piece of string (in the manner of nunchucks) and feeding them into the barrel through the bunghole.
One retailer of barrel inserts, who offers to install them into barrels on site, claims the following.
“Compared to using new barrels, the Barrel Insert system could save your winery up to 85% – without compromising quality.”
“They apparently work quite well,” explain one source, “although I’ve never used them.” He added hastily.
These work much the same as barrel inserts but can be used in large vats and stainless steel tanks when micro-oxygenation may be necessary to get best results. I’ve seen inner staves used in a Chilean winery but have never seen them in action in New Zealand, where winemakers tend to be fairly discrete about such non-traditional methods of adding flavour and maturity to wine at a fairly low cost.
If it makes cheap and cheerful wines a little more cheerful without inflating the price I’m happy to endorse the process.