h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I'm pretty certain you don't have to ferment it for "months". I don't for sure whether that was the case at the time, but porter and stout doesn't take any longer to ferment than most other beer styles, as far as I know. If it did, one of our local breweries wouldn't be able to make their porter because they wouldn't have enough fermenters (those big tanks in the picture http://512brewing.wordpress.com/2010/10/27/512-capacity-grows-by-40-overnight/ ) to brew any of their other beers if it had to stay in the fermenters for months at a time.

During the late 18th and early 19th centuries stouts and porters were fermented, in many cases, from 6 to 18 months. The beer was then decanted down to casks to go to local pubs. The strength of these beers was quite formidable, up to 7% in some cases. Porters were thinned out in the 1800s by mixing less long term fermented beer with fresher too.

The CAMRA website and other various books on the history of London Porter in particular can assuage any concerns you may have about this.

Modern breweries don't really make their Porters to the original recipes, due to a number of factories, including better and quicker beer making methods, that is why your local brewery wouldn't have huge vats, unlike the gigantic ones found dotted across the London skyline in the early 1800s.

I can offer you a variety of reading materials too if you like, as I'm pretty certain I'm right

I would be interested to read those.

I'm still sceptical, since fermenting a beer for so long would tie up so much brewing plant, but also because the yeasts would digest all the sugar long before then, and if you kept feeding it with more sugar you'd end up with a brew seriously more potent than 7%.

This is the porter my friends at (512) make http://beeradvocate.com/beer/profile/17863/45617 As you can see, it's 6.8% with less than a month of fermenting.

I do know what you mean about blending beers at the pub. This was common practice when most beer was brewed at the alehouse and before there were many commercial breweries. That's where Old Ale (aka Stock Ale) comes from (meaning a barrel of ale that's been ageing for a while), and Mild Ale too, although back then 'mild' just referred to a young ale of whatever style, so you could have a mild stout for instance, and two, or sometimes even three, different beers would be blended in the glass.

This deserves further investigation, including much sampling of porters

You should try this one for a read, it's actually well written and informative;

Amber, Gold and Black by Martyn Cornell

I've a copy myself. Shows you just how beers were made and how the recipes and methods of brewing changed over the years.

Modern porters and stouts aren't a patch on the old traditional recipes from all accounts. Cornell mentions a porter that was processed for 20 months, with an alcohol content of up to 14%!

Not game to try that one. I do like Meantime's London Porter though, it's rather nice...

That one is already on my list of books to buy, and I follow Martyn Cornell's Zythophile blog avidly And I agree with you about Meantime Porter - delicious. We can get their IPA too here in Austin - I bought two cases from our supplier last year, and despite the relatively high price they sold very quickly. I'm acquainted with the bloke who imports Meantime beers into the US and I know he's looking to add to his portfolio. I tried a bottle of their chocolate stout which he gave me. Yum

Well, I think we're both right and both wrong

I got myself a copy of Amber, Gold and Black and just finished reading the chapter about porter. As far as I can make out, the porter wasn't *fermented* in the vats for long periods (as stated in the entry), it was *aged* in them. A very different thing. And it wasn't exactly a *need* for porter, it was just the way it had happened with particular style. After fermentation the beer could have been sold almost immediately as a mild (unaged) porter, and no doubt some was. That's certainly the way it became (according to Martyn) and the way porter's made today.

There will be a minimal amount of extra fermentation during ageing, but actual fermentation is a process apart. That's why I questioned the wording of the entry.

I would love to have tried some of those aged porters I've had me a bottle of Meantime Porter and that was delicious