‘Super fly’ hits French vineyards
A scary new kind of vinegar fly has been wreaking havoc among the grapevines of France lately. Drosophila Suzukii (pictured) is like a super-charged version of the common vinegar fly I wrote about in this newsletter a fortnight ago. Drosophila can impart an instant vinegar-like taint to wine. One tiny fly can wreck a glass or decanter of wine; it plus a few of its mates let loose in a winery can wreck an entire tank.
David Lloyd, of Mornington Peninsula winery Eldridge Estate (tastings), read the article and replied that a friend in Burgundy had just emailed him to inquire whether we had this “evil” vinegar fly in Australia, to which Lloyd replied, “I don’t think so – yet!”
His friend wrote: “It’s been a problem in Switzerland and Germany for a while now, but the technical arm of the BIVB (Burgundy’s wine board) were a bit surprised when it turned up unannounced last year. They estimate that no more than about 2% of the drosophila population were suzukiis but that once they’ve bitten (into a grape), perhaps that left an entry route for the indigenous flies. It was a relatively warm winter – like this year – so the population was quite high last year – the plum trees near me stunk already in August – some vineyards were the same. We had one from Gevrey and the vineyard itself was very smelly before any fruit was cut. We triaged as normal and then inoculated and finished the wine very quickly – no long soak before (fermentation). After decuvage (un-vatting) the volatile was quite low and the wine seemed fine – but I know that a number of courtiers’ samples have been distinctly whiffy – so best be on alert for that when tasting 2014s…"
According to the European Plant Protection Organisation, which has added the insect to its quarantine alert list, suzukii is native to Asia, and in 2008-9 was found in North American and Europe. The main difference between our common-or-garden drosophila and the suzukii is that the latter lays its eggs in healthy ripening fruit – not rotten fruit. Scary thing, the female has what is called a serrated ovipositor. It uses this to cut a hole into the grape or other fruit, then lays its eggs inside. No-one is the wiser until it starts to pong of vinegar. Before you know it, an entire vineyard is reeking of vinegar. Quel horreur!