Introduction: How to Make 20,000 Pints of Beer.
There are several projects here for small-scale home brewing.
I thought I'd find out how they do it properly.
I turned to the Adnams Brewery, and enlisted the help of their Quality Manager, Belinda Jennings, who I first met in a field in Suffolk...
Step 1: Raw Materials
The thing about brewing is that there are no secret ingredients.
Water, malt, hops, yeast. That's it, for a proper beer.
What affects the final flavour is the way these things are treated.
The softness of the water, how dark the malt is roast, the species of hop, the strain of yeast.
Malt adds sweetness, and provides the sugar for fermentation. Hops add bitterness, especially to balance the sweetness of the malt, and the yeast, of course, turns the sugar into alcohol.
Most brewers (Adnams included) will happily give their recipes, but they won't give their yeast - established brewers have strains that are slightly different to other brewers' strains, and so affect the flavours. Adnams have been using the same strain of yeast since 1945.
Step 2: Preparation and Control.
Malt must be milled, yeast grown and water boiled.
The remains of the milled malt go to be animal bedding - very little of anything is actually thrown away by Adnams.
In 2008, Adnams installed a whole new brew-house. As well as being highly controllable and automated (in-line systems weigh out ingredients instead of sacks having to hefted in by hand), it also recycles the waste steam from the brewing process - it saves 30% on energy costs, but it also means that the brewery doesn't smell of brewing, which is a shame IMO.
Step 3: Wort.
The milled malt is heated and stirred (mashed) with water in the lauter tun, for 90 minutes. This dissolves the sugars and other flavours out of the solid malt, making a liquid called wort.
The heating pattern - how hot, how long, when the temperature is changed etc - affects how much of what flavours are dissolved out of the malt, and will affect the final flavour.
When the wort is transferred to the next tun, the solids are left behind, eventually to end up as cattle feed.
Step 4: Hopping
Hops add bitterness, flavour and aroma to a beer.
Hops added early to the wort cook the longest and add most bitterness (the bitter flavourings are resins, which are harder to cook out of the hop). Hops added later provide flavour and aroma from oils which evaporate quickly when heated.
The timing of hopping has a huge affect on the flavour.
Step 5: The Best Bit...
The actual fermentation.
The yeast that was fed up on wort is added to the hopped wort, and warmed - the temperature is maintained in the region of 20oC. The exact temperature of the fermentation controls the fruitiness of the final flavour; slightly higher temperatures increase the fruitiness, slightly lower temperatures decrease it.
The beer spends three days being warmed, then is cooled to around 6oC for four days to mature.
Step 6: Firkin!
Beer travels to pubs in barrels.
Well, it used to. Actual barrels are quite large - 288 pints - so the vast majority of beer gets transported and sold in firkins, which hold 72 pints.
The barrels are all recycled - flushed with hot water, blasted with steam, and refilled whilst still hot.
The barrels are then moved to the edge of Southwold, to their warehouse with a living roof, ready for distribution all over the country.
Step 7: The Fun Part
Sorry, I mean quality control...
All the brews are tasted as soon as they are ready. The process is very like wine-tasting, except that you have to swallow, because much of a beer's flavour is after-taste. No pansy slurp-and-spit here!
Samples from bottled batches are also tasted regularly through their shelf-life, and a month beyond; this is a non-pasteurised beer, and it is potentially possible for the flavour to alter with time.
Step 8: Art and Science
Brewing is one of those processes, like papermaking and smithing, that is equal parts precise science and black art.
Careful records of what goes in and what comes out have to be maintained for customers, food authorities, the customs and excise...
Samples are taken all through the system and monitored. Swabs are taken regularly to check for microbial incursion (remember, this beer is not pasteurised, so the whole system has to be scrupulously clean).
But, at the same time, the unexpected happens, like the Belgian-style beer that absolutely refused to settle its fines, no matter what they did...
Step 9: And a Little History.
The brewing house was refurbished in 2008, but Belinda took me to see what was left of the old methods.
"Proper" copper tuns and vats that were a pig to keep clean. Steam valves that had to be turned by hand. Wobbly steps that had to climbed with sacks of hops. Picturesque, but unpredictable.
But... look at that view!
Step 10: Credit Where Credit Is Due.
- Fergus Fitgerald, Chief Brewer, who gave permission for the whole thing (but, unfortunately, could not be there the day I visited)
- Belinda Jennings, Quality Manager, who looked after me on the day, giving me access-all-areas and fitting me around her proper job and a visit by shareholders.
- Graham Gilbert and Colin Chambers, who kindly allowed me to take their photo whilst about their work.
- Thanks also to all the other staff at the brewery who put up with me trailing around the place like a lost drunk.
Oh, I do recommend that you favour them with your business - Adnams beers are all in my top-ten favourite brews, and I tend to be fussy about what I drink. They are also very environmentally aware as a company, producing a carbon-neutral brew, pioneering thinner bottles, and building a green-roofed warehouse, all of which got them crowned 'Carbon Innovator of the Year' by the Carbon Trust.
Oh, and about that field...
On the way to the brewery, I had a small, er, incident, and my Mini ended up in a field. Belinda and a colleague, Paul Hester, very kindly came and pulled me out of the field (which is more than the AA would do, despite me being a member for twenty-five years this December!). If they hadn't done that, then this Instructable would probably never have happened.