Friday, 11 May 2012

Bacteria found alive in 200-year-old beer

In 2010, divers exploring a Napoleonic-era wreck off the Åland islands, a Finnish (but autonomous, and Swedish-speaking) archipelago in the mid-Baltic, discovered bottles of champagne and beer that were still sealed and appeared intact. Some of the champagne was auctioned for charitable causes - raising €54,000 for just two bottles! - and a couple of the beer bottles were sent to Finland's VTT Technical Research Centre for analysis.

Some early results were released a year ago, including the discovery of dead yeast cells and live lactic acid bacteria, so what's the news now? Well, according to this week's VTT press release, they've finally published their results properly, including identification of the four lactic acid bacteria species and what appeared to be dead cells of brewer's yeast and a lambic yeast. It adds:

Both bottles contained beautiful pale golden liquids, identified as beer by the presence of malt sugars, aromatic compounds and hops typical of the beverage. Chemical analyses showed that the beer could originally have featured hints of rose, almond and cloves. However, the beers in the bottles examined had not stood the test of time well.

The pale golden colour indicates that the beers were made from unroasted malt. The burned flavour suggests that heating at the mashing stage was not under control. It is possible, though, that a smoky flavour in beer was appreciated at the time. The beers were probably made from grain – barley or wheat or a combination of the two. Hops, of a variety typical of a couple of centuries ago, had been added before boiling the wort. 

The analyses also appear to show they were two different beers - one with some characteristics typical of wheat beer and the other much hoppier than the first, and with different bacterial compositions. A presentation given by VTT on the findings is available as a PDF here.

They're going to sell some more of the champagne next month. The next step will presumably be to try recreating the beers - the Åland government is funding the research in a sort of PR exercise for the islands.

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