Mashing in HLT on (not quite) all-in-one system (side-by-side mashing)

[dannythemanny]

Hello,

I recently posted about my disappointment in trying to brew a big-ish IPA in a 35L Klarstein all in one. I used 6.5kg of grain and only got an OG of 1.041. This is lower than I would have got if I'd used considerably less grain. So I became aware of the limitations of smaller all-in-one systems such as this for brewing higher OG 19.5L batches (I collect 22L in the FV).

I still wanted to brew my 1.060-ish IPA. I read up on reiterated mashing, but while I'd be happy to do this occasionally to brew a *really* big beer, the thought of running two mashes consecutively would make for a really long brew day. For anyone interested, this is what I ended up doing...

Now, while I use the all-in-one for mashing and boiling, I should mention that I have a smaller Klarstein unit that I norally use to heat sparge water (henceforth HLT). So this isn't strictly "all-in-one", but these types of vessels are relatively inexpensive. I remembered that it came with a false bottom that I'd never used. I wondered how I'd get on running two mashes side by side. After conversion completed, I could simply lift the grains over the kettle and drain the HLT over the grains in the kettle. I could then add (cold) sparge waer to the HLT, heat it (this doesn't take long because the grain is already hot and I'm also inclined to believe that sparge water doesn't make a huge difference to extraction, give it a good stir, and again "sparge" the grain over the kettle with these second runnings. This would cut the added time on brewday to a minimum: it might make sparging take an extra twenty minutes or so, and I'd need to clean the HLT out more thoroughly, but not really a big deal. I considered a few options of splitting the grain and water between vessels, ultimately collecting 30L of wort from the mash, as usual (I boil this down to 25L, and leave about 3L in the kettle). Ultimately, I decided to put 4kg of my grain bill in my main kettle and 2.5kg in the HLT.

While the HLT does have a thermostat and false bottom, it doesn't have any recirculation pump or timed automation. While I did a 40-60-70 step mash in the kettle, I couldn't be bothered to adjust the HLT manually, so I just set it to 67C and left it for an hour. I took refractometer readings for each runoff. The "first runnings" of the main mash came out at 1.040 (4kg grain in about 27L of strike water), the first runnings from the HLT came out at 1.061 (2.5kg in 10L srike water). The second runnings from the HLT came out at 1.035, so there must have been a lot of sugar left behind, but by this time I was already way over my pre-boil volume (I obviously screwed up my numbers somewhere).

I didn't quite reach the OG I was after - it fell 5 points short of 1.060 at 1.055. However, this is obviously due to the fact that I ended up with 5L+ of extra wort (I drained 33.5L into the kettle instead of 30L, and ended up with 28L instead of 25). Once I dial the numbers in better, I think I might actually overshoot my target of 1.060, but I think I will be able to refine it so that I can get much more consistency when brewing grain bills over about 5kg, at which point my all-in-one system's extraction seems to plummet. This reminds me -- to anyone still reading, I never find that I get correct boil off/dilution gravity as calculated by the Brewer's Friend calculator. If I put in that I have 33.5L of 1.050 wort, and boil it down to 28L, the calculator says it should be 1.060, but I got 1.055. This always happens with every brew - could it be measurement error across gravities in the refractometer I'm using?

Last thing, at the end of the day, I tried to lift the kettle up off the floor to drain it into the fermenter, and my lower back exploded. Slipped a disc. Not good. Time to invest in either a pump or a hoist - I'll start a separate thread!

 

[simon12]

I have never used an all in one so sorry if theres a reason this just won't work. Could you just batch sparge? ie if you need 32L to get your required batch size mash with 15L, after the mash drain it to a bucket or something then add half the rest 8.5L to the mash and recirculate for 10 mins, then drain that to the bucket and repeat with the last 8.5L of water. Finally remove the grain and add all the liquid back for the boil.

 

[dannythemanny]

I have never used an all in one so sorry if theres a reason this just won't work. Could you just batch sparge? ie if you need 32L to get your required batch size mash with 15L, after the mash drain it to a bucket or something then add half the rest 8.5L to the mash and recirculate for 10 mins, then drain that to the bucket and repeat with the last 8.5L of water. Finally remove the grain and add all the liquid back for the boil.

In essence, I am kind of batch sparging. After conversion, I add water to the HLT, heat it and give it a good stir, then drain it. The only difference is when I drain it, I run it over the other grains. I have thought about exactly what you describe, but there are a few reasons I decided against it, chiefly that it would necessitate another container, large enough to accomodate most of the preboil volume of wort. I'm pretty limited space-wise, so trying to streamline things as much as I can. Another issue is the deadspace in my all-in-one is ridiculous. The grain sits 45mm off the bottom of the kettle, and there is a 20mm gap around the edge of the grain basket. The grain is kind of squished into a smaller area in the kettle by virtue of being in the basket, so the smaller volumes of liquor to batch sparge a couple times can mean that for larger grain bills, a good chunk of the grain wouldn't see the liquor if you see what I mean? I used to batch sparge in a cooler with a SS braid, and that worked a treat with very little dead space. I had to get shot of it due to limited space - I didn't want to have to go up in the attic to get it every time I wanted to brew!