The wine industry, at least in Australia is undergoing one of its periodic upheavals. The wine industry is fed up with the cork closure and are moving to stelvin closures. So great are the problems, such as cork taint that affects 4%-7% of wines, cork wood taste and random oxidation that they can no longer be ignored. Yet world wide the wine industry has also debated that perhaps one of the good points of cork is that it allows a slow ingress of oxygen which is thought to be necessary for red wines to evolve. Well a recent study by two Southcorp wine scientists, Allen Hart and Andrew Kleinig, has just blown up that idea.

They have shown in a study of red wine, they used Penfolds Bin 389 1996, and sparkling red wine using Seppelts sparkling burgundy, that the expected process of ageing takes place in a the bottle even when no oxygen can enter through the closure. By this we mean the bottle has been sealed with the Stelvin screw cap of which you are familiar and with the sparkling red the conventional beer bottle top, neither of which allows air to enter the bottle.

Now a good cork is also a good closure but the problem is that no one can tell what are the good corks which would let in little or no oxygen as the wine evolves and a poor cork which lets in to much oxygen and causes early ageing and final oxidation which of course destroys the flavours of the wine.

So all the qualities that we look for as red wines evolve to maturity can take place just as well, if not better with the screw cap and more importantly they will all evolve more or less at the same rate. So 4% to 7% of the wines will not be tainted and let us guess, 20-25% will taste better because they will not have cork wood taste or early oxidative problems that dampen the flavours. Now a saving of 30% of bottles that drink better is a very large gain for consumers.

As well this study showed that plastic corks are very poor and should only be put in wines that are going to be consumed soon after bottling.

The one small problem is that wines that evolve in what scientists call an anaerobic environment of no air intake can have a slight reductive smell and flavour which to you and I is a faint pong. This will blow away if you decant the wine. The study says that ‘the levels recorded were not considered to be unacceptable for commercial wines’.

And one other finding I gleaned from the paper was that sulphur levels are a half to 60% lower after four years of bottle age. If you suffer from asthma and believe it is triggered by sulphur then drink aged reds. Also an observation I have made over the years is that those drinkers who react to red wines will find them pleasant when aged. Something in the maturing changes the young aggressive chemicals that give you headaches.