International Homebrew Project : Brewing A Big, Hoppy, Scottish Mild

As part of the International Home Brew Project (IHP), organised by Alistair at Fuggled, I recently brewed a strong, and probably quite bitter, Scottish mild.

This account highlights some of the challenges presented by this high gravity beer.

malt for the International Home Brew Project mild

Although I’ve not participated in the IHP before, I liked the idea of home brewers across the world simultaneously doing the same thing. I was also tempted by the opportunity to explore unfamiliar brewing areas.

The Recipe

After a period of voting, we (those taking part) chose mild for this year’s brew. The recipe, which dates from 1853, comes from William Younger’s Abbey Brewery in Scotland.

As Alistair explained, mild in those days meant that the beer was drunk quickly, while still young. It seems to have been quite different from mild as we now know it.

This mild is a high gravity, high bitterness, all round big beer. The 23 litre recipe calls for 12 kg of malt and 91 IBUs.

As usual, I planned to brew using BIAB and, realising that a full batch was out of the question, scaled the proportions down to 15 litres. However, seeing the pile of malt beside my brew pot it was obvious that even that was asking a lot of my set-up.

On brew day I reduced down again, this time to 10 litres, which left me with the following recipe:

Recipe Volume
10 litres

Start Volume (Brew in a Bag)
19 litres

Pale Ale: 6 kg

Mash Time
120 mins

Mash Target Temperature

Kent Goldings (5.3%): 75g pellets for 90 mins
Fuggles (4.8%): 59g pellets for 20 mins
Fuggles (4.8%): 17g pellets Dry

Danstar Windsor Ale

Original Gravity

Final Gravity

Note that I adjusted the malt efficiency to 60%, which is the average I’m getting out of my equipment at the moment.

The Mash

As well as taking part in the IHP, I was also using this brew to test the Brew Target software.

I’ve written about that in another article, but for now it’s enough to say I put complete faith in its calculations. My starting volume of water was determined by the programme.

Once the water was up to temperature, the malt went in.

Pouring malt into mash for International Homebrew Project

The grains sank slowly into the water.

dry malt entering mash

The pot and bag were close to capacity, or probably even a little too full, causing the malt to group together in dry-centred lumps. After patient stirring it eventually separated into an even mash.

International Homebrew Project mash

Temperature control was surprisingly straight forward. I’d imagined that with such large quanities of malt the mash would need reheating, especially due to the long two hour mash.

However, other than giving it a quick burst of heat after the grain additions, the temperature held without my interference.

target mash temperature

Getting the bag out was a big physical effort. The volume of water that came up with it not only made it extremely heavy, but also necessitated an extended period of draining.

heavy brew in a bag bag full of malt

After most of the wort had fallen back into the brew pot, I also got another litre or so by leaving the bag to drain while I started the boil.

draining wort from bag

The Hop Additions

I used Brew Target to tweak the hop additions to match the alpha acid of my pellets, adjusting the weights until the target 91 IBUs were achieved.

Although the software suggested (surprisingly) larger amounts than my manual calculations, I decided to trust it. I want to know whether it works or not.

The huge hop additions filled the wort which, after cooling, had a large cloud of green.

wort full of hops

The original gravity measured 1.090, a bit short of the target. Although a lower efficiency can be expected with high gravity beers, it was nevertheless disappointing.

If nothing else, this brew has reinvigorated my desire for better BIAB efficiency.

This is still big beer, but the shortfall in gravity has left me wondering about bitterness. Re-running the figures through Brew Target with the actual efficiency (around 50%), the IBUs come out around 110.

It will be an interesting mild.

almost 10 litres of mild in the fermenter

Brew Target’s batch volume prediction was almost perfect.

mild in fermenter before sealing

Following the IHP timeline, I’ll drink and write up at least one young bottle in around six weeks. However, I’ve a feeling it’ll take longer for the bitterness to properly settle down.

Thank you Alistair for publishing the recipe and organising the project. Whatever the outcome, it was a fun brew.

Update: To see how this brew turned out click here.

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  1. I do a kind of hybrid method of brew in the bag, where I mash in a picnic cooler but with the grains in a bag. This approach allows me to draw off the first runnings and then sparge a couple of times for added efficiency. I average about 75% this way.

    • John

      Thanks for the tip!

      Since brewing this I’ve been experimenting with the drainage stage, thinking this is where my efficiency problems may be solved. Over the course of 45 minutes, and using the fermenter as a holding bay, I now gently rotate the grains inside the bag to coax out trapped liquid. Meanwhile the rest of the wort gets up to boiling temperature.

      Using this technique I recently mashed a porter with 75% efficiency.

      I’ll take your advice on board and look at a full sparge stage next time I brew.