First Half Mash Brewing Attempt

Here is an old article I wrote explaining how my first ‘half mash’ home brewing attempt went.  I’d done a few kits, but wanted more control on the beer and ingredients, and I wanted to use some real hops too!  I did some studying, so hopefully there’s not too many mistakes in here!

My special bitter in 2nd fermenter

My special bitter in 2nd fermenter letting it ‘condition’

Well I’ve just made my third home brew of year, and this time I’ve upped the level from ‘kit’ to ‘half mash’ (or extract brewing). While it’s still not ‘full mash’ brewing (which is buying the grains and doing pretty much everything except growing the ingredients yourself), it still feels much more like making beer than making up a basic kit.

I’ve started my new level of brewing buy trying to make a London style bitter (higher hopped than Yorkshire bitter style), which should reach about 4.2% alcohol (about 21-22 litres of). I’ll know how it’s gone in about 4-5 weeks or so. Here with pictures is how you go about extract brewing.

1) Choose your recipe (you can find recipe’s online, in books, or even the simple 60p leafletI bought has some basic starter recipes in different styles).  Extract brewing involves buying malt extract (either in 1.5 / 1.8kg tins in liquid form, or as spray dried malt), which is where your sugars, colour, and malt taste come from, and then selecting speciality grains (to add more flavour), and hops (which adds bitterness, and the hoppy aroma).  You also need some yeast of course, and it’s worth getting a good quality one, which goes with your beer style and strength (Belgium high alchohol yeasts when you need to go past 7%).

2) Buy your equipment – as I had been brewing kits, I already had a couple of fermentors (clear plastic ‘water bottle’ style one for secondary fermentation, and a screw top sealed one for primary), I’ve also got an older ‘bucket’ which I have kept for preparing my brewing liquor (that’s treated water in laymans terms).  I also aready had a good syphon, cleaning / sterilising stuff, and other bits n pieces, including the very important thermometer (I’ve gone digital as the old glass n mercury one really doesn’t cut it these days).  To brew extract, I had to also buy a boiler (a stronger heat resistant bucket with attached heating element and tap), and a wort chiller (spiral of copper tubing which you flow cold tap water through to cool the boiled ‘wort’ quickly).  I also bought an aerator – which is a fishkeeping air pump and ceramic stone – which isn’t essential but I thought I’d get to really get a lot of oxygen into the wort for the yeast to use (and I really got a strong fermentation – which might be linked to its use).

So with some pictures, here are the steps I undertook to make my London Bitter, maybe it will inspire or help you with your brewing (or maybe you’ll write and tell me how I’m doing it all wrong!?)…

Beer equipment: Boiler

Beer equipment: The boiler, and a good stirring paddle. Clean EVERYTHING!

1) Clean and steralise everything!  Even though the boiler will obviously hold boiling liquid, I thought I’d use some Milton tablets to pre-steralise the boiler – letting some of the fluid flow out through the tap to ensure that was clean and germ free.  I did my usual and soaked my fermentor for 24 hours in VWP (powdered bleach/cleaner you add to warm water), and I always through in everything I might use during my beer making – teaspoon, bubbler airlock, bung, big paddle, small bowl for preparing the yeast etc.

2) In my 25 litre bucket, I filled it with tap water the night before I was going to brew, and added a crushed campden tablet (got em from local Wilkinsons of all places).  They are often used for wine making to kill the yeast at the end, but also I have read they are used to take the chlorine and associated chemicals out of tap water (which is put there by the water companies to kill germs I guess).  Chlorine makes homebrew taste.. well like homebrew made with tap water I guess – you can smell the chlorine in our water compared to filtered water.  So I popped a lid on the bucket, and let the water clean up (I’m not sure if the tablets work very quickly or need longer, so I took no chances).

3) Next morning, I have my brewing liquor now ready to roll – I used my syphon to transfer half of it into my boiler, and then just picked it up and poured the rest in once the weight was down.

Steeping grains at about 65c

Steeping grains at about 65c

4) Steeping my grains. Attached my ‘sparging and mashing’ bag to the boiler (see picture) – the bag is nylon and keeps the grains away from the heating element, to stop scorching and the element cutting out.  Then poured in 500g of crystal malt grain – while I wasn’t doing a full mash so wasn’t adding lots of KG of grain, I still want some fresh flavour (and body and colour).

The water is then heated upto 65c and kept there for 30 mins, which ‘steeps’ the grains – it looks like you’re making a very large brew of tea!    Once 30 mins were up, I turned off the power for while, and removed the mashing bag, removing the grain from the hot water.

Checking temp for steeping

Checking temp for steeping

5)  While the grains were steeping, I put a large saucepan of water on to boil, and in that put the two 1.5kg tins of pale malt extract – which is what will supply the sugar and malt flavour to my beer.   British bitters can be varying colours, but they are fairly light – so therefore pale malt is fine.  Putting the tins into boiling water makes it easier to pour the malt out, making it much more fluid.

When ready, just use a tin opener on the tins and pour the liquid malt into the boiler, using my big stirring paddle to help stir it in.  As I wanted the strength to be just over the predicted 4% I also stired in 500g of spray dried medium malt, to also add a bit more body and colour to the beer.   Once all stired in, I set the boiler themostat to full power to get the heat into it.

Wort at rolling boil with hops added

Wort at rolling boil with hops added

6) Rolling boil – using my digital thermometer to check the temp had reached boiling point (in fact there’s little need, it’s pretty obvious when that point is reached, the wort really starts to churn and boiling point – be careful with it!), I then added 90g of hops, saving some of my 100g for added right at the end. Hops are added for two reasons, to add bitterness to the beer (which you boil in the wort for the whole boil), and to add aroma (which you add in very late on – sometimes even dry hopping by adding in the barrel / fermenter).

I then left the boil for an hour – turning the power down to maintain a rolling boil.  I left the lid 1/4 off, as you’re meant to be letting some of the unwanted chemicals boil away I believe.

7) Wort chiller – the wort chiller is carefully lowered into the boiling wort and left there for the last 15 minutes, to ensure all bacteria is killed.  For the last five minutes of the boil I added my last handful of hops, to hopefully give it a nice hoppy aroma.  Once the time is up (I gave it about 1hour 15.. but longer is often advised), power off, and cold tap on!  I bought a cheap(ish) garden hose tap adaptor, and managed to fit it to the plastic hose that came with the wort chiller (only after softening the hose up with boiling water.. but at least it’s a snug fit!).  I also bought some hose clips to really secure the plastic hoses onto the copper wort chiller – as I didn’t want to ruin my beer or kitchen with water leaks.  It’s quite amazing, but by pumping standard temp tap water around the copper tubing, chilled the wort from 100c to 25c in about 35 minutes.  You want to get it cool as quickly as possible, to reduce the chance of bacterial infection as it cools (it would take HOURS on its own), but also to get what’s called a ‘cold snap’ – unwanted proteins drop out of suspension if you chill quickly, rather than re-disolving back into the wort.

During full boil wort chiller added

During full boil wort chiller added

8) transfer wort to fermenter– as the temp was down to 25c, I could now allow some air into the wort (you don’t want to oxidise your wort, which happens if it’s too warm when you let air mix with it).  So I just opened the tap and let the wort drop naturally down into the fermenter, which really foamed it up (a good sign of oxygenation).  I also then dropped my aerator stone down into the wort, and turned on the air pump, giving it another 10 minutes or so.

9) YEAST! Oh while I was letting the wort chiller do its thing, I prepared the yeast – it was good dry yeast (I went for a Safeale yeast S-04)  – but I’ve read its better to ‘prove’ the yeast before adding, in case it’s a dud (I had two packs ready, just in case).  Boil some water up, and pour a little into a container (I use a small glass mixing bowl so I can see it working) – let it cool back down to 35c (cover using some foil to keep the air off it) – and then pour in the dry yeast (I even steralise a small pair of scissors to cut the pack open).  Be gentle as you mix it in.

DON’T ADD SUGAR (A mistake I have made – the yeast will adapt to ‘eat’ simple sugar, and then be surprised by the compexity of the sugars in your wort).  Leave about 30 mins – you should see the yeast is ‘alive’ now – a good head of yeasty foam.   Pour the yeast mixture into the wort when it’s no more than 25c (ale yeast usually works between 17-25c).  Gently stir in.  I added 1/2 teaspoon of Youngs yeast nutrient too – just for good measure.

Wort and yeast in fermenter

Wort and yeast in fermenter

10) Stand back!  Add the lid to the fermenter, insert the bubbling airlock into the rubber bung, then tightly fit to the lid.  There will be a period of time when nothing much seems to happen (the ‘lag’) – while the yeast gets to know it’s surroundings, but after a few hours, I could see/hear bubbles running up through the bubbler.   About 18 hours later, my yeast had really gone mad – the strongest ever fermentation – reaching all the way up to the bubbler airlock (oops) – which is a BIG head of foam in my fermenter!  Not sure if that’s cause of the yeast, the wort, or the extra air I got into it this time – or maybe a combination of everything – seems a good sign anyway.

To keep the light off the beer as it brews, I just cut a small hole in black bin bag, and pull the bag over the fermenter, allowing the airlock to poke through.  Obviously I check it every few hours to see how it’s doing, and that the temp is about right.

Author: Krispy Brown

EX-CAMRA member and real ale and craft ale fan. I've left CAMRA as I feel they've become more about gaining members (and money) and their petty narrowmindedness around the whole craft/keykeg/cask puts me off them. Good beer is good beer! I do the odd brew myself - having spent a couple of grand more than I should on home brew kit (Braumeister and SS Brewtech gear). Always learning about the craft and the ingredients. I've a blog post here about a day with a local craft brewer making a new beer. I can often be found propping up the bar at Peterborough's best (only) craft beer bar, The Stoneworks. 22 lines of great beer, and decent gin too! I'm probably known by too many of my hometown's landlords, oops. I created the local CAMRA Peterborough Beer festival mobile web app several years ago, and am a regular festival judge helping pick the champion beers. Developer (PHP, Wordpress, Java), Webmaster of many sites, husband and cat owner. I also help put on DIY Punk gigs in my spare time, as part of group of mates called "The Scary Clown Presents...".

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