The less you handle wine the better. By ‘handling’ I mean violently mechanically agitating, any manipulation which may expose the wine to air, cause dissolved gas to come out of solution, de-polymerise or otherwise disrupt flavour molecules. It is therefore desirable not to use pumps or filters when transferring wine between tank and barrel.
But on the other hand, during the ageing process it is necessary periodically to move the wine from barrel to tank, allow the lees to sediment, and then return the wine to clean barrels. You don’t want to do it any more than you need to – maybe two or at most three times over the 18 months the wine is maturing in barrel – but by removing yeast cell debris the wine is freshened and clarified. This can of course be achieved by pumping the wine through a filter, but in addition to shaking the wine up that strips out flavour compounds. For fine wines the altogether gentler process of siphoning the wine off the lees without the use of mechanical pumps or filters (racking or soutirage) is generally agreed to be better. But it’s time consuming and siphoning under gravity may be impractical in an industrial winery constructed all on one level.
In planning the set-up at Mount Terrible, there were a number of reasons for our decision to go down rather than out.
1. There wasn’t the room to go out.
2. Underground cellars naturally hold their temperature.
3. After the bushfires of 06 and 09, the attraction of having somewhere we could go to avoid being burnt to death was considerable.
And 4. The difference in height between the above-ground and cellar floors would enable us to conduct all wine transfers under gravity.
The last was not the principal consideration when it came to the decision to bite the financial bullet and dig, but on a day-to-day basis the ease and flexibility it has brought to wine-handling operations has come as a pleasant surprise. Once the hoses are gassed, we can fill a barrel from tank in less than 4 minutes with scarcely a gurgle. And to reverse the process, all that is required is to slide the tines of the hand-operated fork-lift (aka carpet-lifter) under the chosen barrel, lift it clear of the rack and roll it to the lift, position it beside the tank, elevate it and allow the contents to drain. How Burgundian is that?