Brewday 2 April - mini-mash based on Royal Oak recipe

[inthedark]

This is my second attempt at a mini-mash, only this time with a difference. I've decided that keeping a steady temperature using a gas oven is very nearly impossible, so decided to use a temperature controlled water bath instead.

So, here's the rig set up - one of those boilers from Tchibo with a flimsy 8L stock pot from eBay, and a couple of tins to stop it floating.



The recipe is one scaled down from a modified Dave Line recipe for EP Royal Oak, from the recipe section. I divided by 23 then multiplied by 5, then rounded so I wouldn't have to weigh out 0.3g of hops...

765g Maris Otter (the pale malt I had in the cupboard)
54g Crystal
100g Flaked barley
80g brown sugar - actually demerara - again what I had in!
12g Fuggles 90mins
6g Goldings 90mins
3g Goldings 10mins

planning on dry hopping a couple of g of Goldings to keep close to the recipe.

pinch of Irish Moss
Gervin ale yeast

So, temperature control seems to be ok:



and keeps pretty steady right to the end:



Bonus of this method is that I used the boiler as a HLT too, using the water bath for sparging.

Sparging - had some trouble keeping the grain bed temperature high enough, but seemed to be much simpler than last time:



Boiling:



Cooling in the bath:



And straining from the hops:



Yeast is awake!



Waiting for the break to settle out, time for my reward - a pint of the last mini-mash. A bit weak but worth the effort!



Once I'd racked off the break material, I've only ended up with 4L at about 1043. According to BeerToolsPro, that's an efficiency of just under 50%! Got to find some improvements - any suggestions?

[SteveD]

Dave Line advocated a floating mash tun system for those with big boilers. You were following his method as well as his recipe. His Royal Oak was my first AG brew. Came out lovely (they do, after extract brews) and the 5 gals brewed was drunk in 3 days. I got 1056 most probably because I hadn't even thought of calibrating vessels then and what I thought was 5 gals was somewhat less.

[inthedark]

(I noticed the picture of the lauter tun and the grains looks a little low on water)

I wondered whether this might be a problem - I used 2L as per your instructions but of course half of that disappears straight away into the outer bucket through the holes in the bottom. So the benefit from letting it sit for 10 mins in the sparge water seems to have been lost.

[inthedark]

Just been to have a look and yes, the nut does hold it up a little, but not a great deal. I've also cut the lugs off just in case but they're standing pretty clear of the rim.

I'll try the larger sparge volume next time - I'm not relying on a flask, so can be a bit flexible. Thanks for the tip. I'll get some ph papers on my next order too.

Might have another go on Friday - now I've got the temperature control sorted there's no stopping me

[inthedark]

The ph strips and CRS have arrived, so now I'm really confused!

I've read through the Thames Water thread in the Brewing Liquor forum and checked the local water report and come to the conclusion (with others) that the report is not going to help me in the slightest.

So, if I check the ph of the mash and find it's too high, can I add a bit of CRS then, or is it already too late? Should I just start with a 'standard' amount for South of England hardness and alkalinity, see what it does to mash ph and adjust the next one? I really don't want to do a mash without treatment just for a control - seems a bit of a waste of ingredients.

[Andy]

You can add it direct to the mash and stir, take a reading and repeat if necessary. Although I believe it's best to add it direct to the mash strike liquor before doughing in as this lets the CRS reaction take place before the mash is underway*. Start with say 0.2ml of CRS / litre of mash liquor and see how the pH turns out in the mash, if still too high than add 0.1ml CRS / litre etc etc


* you could move to this method for future brews once you've worked out how much CRS you need to add (using the add-direct-to-mash approach)

[inthedark]

Thanks guys

I had already considered that adding a small enough amount to a mini-mash would be tricky so I'll try Andy's suggestion of treating the liquor first - I normally have a large amount prepared since I use Campden tablets to remove chlorines. Anything smaller than half a tab is impossible!

I'm nearly ready to progress onto bigger batches though - getting the last of the equipment together, just need to find a way of attaching my IC to a water supply (none of my taps seem to be the right shape for normal hose connectors )

[Andy]

Thanks guys

I had already considered that adding a small enough amount to a mini-mash would be tricky so I'll try Andy's suggestion of treating the liquor first - I normally have a large amount prepared since I use Campden tablets to remove chlorines. Anything smaller than half a tab is impossible!

Don't forget that you measure the pH of the mash, NOT the pH of the liquor before doughing in And as DaaB mentions, go low on CRS additions initially as you can always add more to the mash but can't take it out

[inthedark]

Well my latest attempt appears to have given me a slightly increased efficiency - up to 60% now. Just wondering, I've been allowing the break material to settle because none of if appears to be filtered by the hops - I've adjusted volume and check SG after racking off the break - is this right?

[inthedark]

I had to go out before it had settled out last night, so took a chance and left it in a sealed demijohn overnight to settle. I suppose if lost about half a litre to trub and then topped up to the 5L mark, which is when I checked OG.

I suppose if I'm comparing against full batch efficiencies where they don't rack off the trub then I should recalculate - after all, I'm really using the mini-mash to iron out some of the processes before I commit a large amount of grain to a batch (and obviously my boiler's not quite ready to go yet!)

[inthedark]

Sounds pretty complicated - I'll give this another read through and see whether it might help me. The bit about factoring in the dead space may be important. I've looked at your pictures again and noticed that your tap is almost right at the bottom of the outer bucket, whereas mine is fitted a bit higher.

Try to avoid an excessively vigorous boil and keep the pan topped off to around 5 1/2-6L (occasionally add a drop of cold water every now and then).

I did wonder about how vigorous the boil should be, as I heard that if it's too vigorous you can drive sugars off - is this likely to be significant? I don't know how anyone would be able to describe the ideal boil vigor in words!

The other area which I'm not confident is the runoff - how much do you collect and recirculate each time on average? I wonder whether I'm getting far too much liquor running straight through the grains without allowing them to settle and doing a good job of filtering.

[inthedark]

With the run off I tend to collect all the wort until the grains settle and slowly and gently return it to be filtered.

Ahh - all at once? I've been collecting small amounts (~1/2 pt at a time) and returning them to the grain bed - would this be better running off completely into a large jug and re-filtering it through the grains?

[inthedark]

Yes, I increased the strike liquor to 2.5L and used 3L for each batch sparge

No, not all at once, just so they aren't swimming in wort. (have you increased the volume of mash liquor you use?)

I meant, do you run off all at once, then gently return that to the wort, or run of small amounts at once like I've been doing and returning a little at a time?