Gruit Ale, attempt number 2

Viking, Saxon, and Early Christian Irish cultures

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Gruit Ale, attempt number 2

Postby the_power on Fri Jun 05, 2009 12:13 pm

So, as many people know, hops in this part of the world are a reasonably recent invention. They are a bittering agent, as well as an antiseptic. Their smell alone can calm, and their active ingredient mimics estrogen in the human body. Before, and for a while, alongside, Brewers added "gruit" to their beers as a flavouring, preservative and ... recreational abilities.

I've tried a gruit ale before with limited success. I sourced my additives locally (wormwood, yarrow, mugwort) from a Chinese medicine & herb shop in Dublin. I cheated, by using Dry Malt Extract (DME, mostly dextrose - a complex sugar, made from malted barley) as well as small amounts of real grain. I boiled it all up for a while, then let it sit with some ale yeast for a few weeks. The end result was..unpleasant. It turns out brewing is harder than I thought.

The first mistake was that I used ingredients from a chinese medicine shop. As you know, chinese traditional medicine was invented in the 1970s by Mao Tse Tung to keep rural medicine costs low by pretending to provide doctors. The herbs they use are usually for placebo effect only, and have little, if any, active ingredients. So, I contact, a Canadian crowd growing herbs for brewers - they sell only the active parts of the herb. So, you don't get bark & wood in your mugwort, just the flowering tips. Joy.

My next mistake was that I only partially understood the chemistry. Temperature is *crucial* to brewing from grain. Starches are complex carbohydrates made from thousands to millions of sugar molecules in a long chain. Starch dissolves around 80C in water. if you don't get it that hot, you don't get much out of the grain. Seriously...try dissolve a banana in 50C water. To make 25 litres of strong beer, you need 13kg of grain. 13kg of grain in a 20 litre cookpot (sufficient for mead making) doesn't fit enough water to soak & stir it all. The next bit about brewing is that as soon as the grain is soaked, you have to drop the temperature (I kinda forgot this). Why ? Grain has enzymes in it that turn starch into sugar - needed by the plant to grow. If you want them to start acting involuntarily, you need to provide the correct temperature. This is where I really screwed up. 67C is the temperature where the enzymes work effectively, cutting the starch up into individual sugar molecules. If you keep your grain mash at 67C long enough, you'll have a bucket of dextrose, which will ferment out into a thin, flavourless beer (as everything will be fermentable). Think something like Coors lite. If you keep it at 71C, you will end up with a bucket of Dextrin; molecules that are 3 to 6 molecules long. Technically sugar, and kinda sweet, but not something yeast can digest. So, the beer will end up sweet and strong tasting, with little alcohol in it. Also no good. My first beer - I boiled the crap out of the grain. So, yeah, I got flavour, but also got loads of cloudy starch. The end result was a soupy mess that tasted of christmas trees.

On tuesday, I tried a second time, this time all-grain (no DME) beer, with 50g of each of Mugwort, Yarrow and Labrador Tea (in place of the now-extinct Marsh Rosemary), half the herbs boiled with the wort, the other half in a muslin bag (well, bundled in a J-cloth) and dipped into the fermenting mixture.

So, the plan was to keep the wet grain mix at 68-70C for 85 minutes, to make sure all of the starches have been broken down into a nice mix of dextrose and dextrin. You might ask 'how the hell do you do that' ? Well, I failed. I kept it on the hob, turning it up & down as I could, measuring with a thermometer and adding cold or boiling water as the time required. Once, I accidentally let it get back up to 80C for 5 minutes or perhaps more. Guess what happens ? Those nice enzymes that turn starch to sugar...break up. Leaving me likely with large amounts of starches floating around in the beer - not fermentable, and not sweet. Worse of both worlds. (German Wiess beers do this on purpose with a small amount of grain that's not mashed etc. properly). How much of that happened ? I've no idea. I'll find out, I'm sure. Turns out the correct answer was to heat water to 80C, and pour it into the mix, mash it, it'll cool quickly in contact with cold grain, and settle around 70C. Then turn the hob off, insulate the mashing tun, and stir occasionally so you don't have cool/hot spots, and measure the temperature repeatedly.

You must ask the heck did people 1000 years ago manage to keep a 300 gallon copper tub at exactly 70C for 85 minutes, without modern thermometers (shunned by brewers until the early 1800s) ? There are a few ways. 70C is "as hot as can be bared by skin", apparently. It's also as hot as you can get water without steam obscuring the mirror surface. Another way is to mix 220 gallons of boiling water with 100 gallons of cold water. Fair play to them.

Even still, early industrial brewers made mistakes. If it turned out to have little alcohol due to the initial mash taking too long (like what happened my beer) they often added bad gin to it to make a cheap drink (whose name escapes me). If the temperature dropped, and they had a high-alcohol beer that no one would drink (well, they'd drink it today..), the beer would be sold off to the distilleries for recycling into gin etc.

So, give me a week or two, and we'll see how it turns out. Likely badly. But, I do have more botanicals to try another batch, this time armed with more knowledge (including a need for a bigger - and insulated mash tun. 6 hours of work (at 15 quid an hour?), 50 quid of grains, 30 quid of botanicals, 8 quid for yeast, to make 50 pints of beer though. Ow. Not exactly a money saver, especially if you screw up.

References: - Great intro to brewing, leading onto all-grain brewing. You kinda need a scientific background to follow some of it. - recipes & advocacy site for Gruit Ale - brewing botanicals of all sorts
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Re: Gruit Ale, attempt number 2

Postby ronanocaoimh on Mon Jun 08, 2009 12:04 pm

Even still, early industrial brewers made mistakes. If it turned out to have little alcohol due to the initial mash taking too long (like what happened my beer) they often added bad gin to it to make a cheap drink (whose name escapes me).

......Guinness????..... :D
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