Well, after countless discussions between wine experts, scientists and consumers about which closure is best, the jury is in and the results are plain to see:
The Australian Wine Research Institute did a study and, as shown in the photos below, the screwcap does a better job of preserving color and freshness in white wines. The screwcap is the leftmost bottle (black top), and the others are different corks, and synthetic closures (plastic, and cork composites).
After just 28 months (1st row of wines) the difference in color is remarkable. Generally, the flavor change is roughly proportional to the change in color.
The 2nd and 3rd rows at 5 and 10 years respectively are less interesting because who would keep a white wine that long? Still, I bet the wines on the right are undrinkable.
As you can read below, the “Screwed Wine” had, at least for the blogger, “a full yellow colour, with a minerally, flinty edge to the attractive honeysuckle and citrus fruit nose. The palate has a lovely focused fruit quality to it with pithy citrus fruit and a hint of grapefruit. There are also some subtle toasty notes. Very attractive and amazingly fresh for a 10 year old…"
We used screwcaps on some of our Juliet and Isabel wines. For those of you who enjoy these, know that you can store the wine for a bit without worries. In a year or two we will taste the first of these wines that received screwcaps and will report back.
Thanks for your support and we’ll see you at the winery.
–Tell us how you feel about screwcaps vs. corks for wine?
Research Study Article:
These bottles are all 1999 Clare Valley Semillon made by Kerri Thompson of Leasingham Estate. The bottles were part of an experiment conducted by the Australian Wine Research Institute and were sealed with various natural and synthetic cork closures, with the exclusion of the bottle sealed with a screwcap (far left).
Sensory evaluation confirms our visual intuition: the screw-cap sealed bottle retained its freshness and prevented oxidation far better than any other kind of closure. UK wine journalist Jamie Goode tasted the wine and reports on it here:
So, some 10 years and eight months after bottling, how does this wine look? It’s a full yellow colour, with a minerally, flinty edge to the attractive honeysuckle and citrus fruit nose. The palate has a lovely focused fruit quality to it with pithy citrus fruit and a hint of grapefruit. There are also some subtle toasty notes. Very attractive and amazingly fresh for a 10 year old Clare Semillon.
These results are important because they tell us two things. First, screwcaps work very well when you’re trying to age wine. Second, Australian whites wines have staying power and longevity when bottled and stored correctly.