Well, that turned into a bit of an epic day yesterday. Started out at 12:50 by measuring out the water and weighing the ingredients, got everything cleaned up again by 21:20. I've learned a number of valuable lessons, including the fact that kettle and brew fridge shouldn't share the same extension lead. Don't ask ...
And of course the 3.5L of sparge water will make a difference to your OG as well.
To be honest I'm not entirely sure how to deal with the discrepancy that is my counterflow chiller. Yesterday I started with the chiller more or less empty and filled my kettle with the requisite amount of strike water - 22.57 litres, and the sparge water heater with the right amount of sparge water - 11.79 litres. OK, in both cases I might have been a little bit off due to using a combination of 5 litre and 1 litre bottles as measuring devices, but I'm sure I was in the right region.
The chiller stayed empty until a couple of minutes before end of boil (was meant to be 15 but I forgot, so more like 5) and I didn't drain it at the end which means I have that loss to add to other losses like boil-off, etc. Going forward, should I measure and add the chiller capacity to my strike water volume in order to get closer to the numbers? That feels wrong because I'd still be diluting the fermentables, so maybe there's a setting in Brewfather somewhere. Need to explore more anyway - had a quick gander last night and found the same SG / temperature calculator that was patiently pointed out to me in an earlier message.
Let us know your OG when you take a temperature correct reading I bet you are not miles away
Funny you should say that, but after chilling to 20 ℃ (and before pitching yeast) I was at 1.050, which is 3 points above the post-boil / OG target of 1.047. I'm a bit puzzled by this. Had my pre-boil been on target (instead of 6 points low) would I have had an ever higher post-boil?
Did you stir the mash? I often get a low efficiency if (most of the time) I forget to stir the mash.
I have to admit this area is one where my lack of knowledge makes me uncomfortable. Nowhere did it say to stir the mash other than at dough-in, and I only did that after the 20 minute rest period which Brewtools recommend in several places, even though their wording doesn't make it 100% clear whether that's the first 20 minutes of your mash time or if it's 20 minutes followed by your mash time. I went for the former, and resisted the urge to give it a stir at the start, despite some grain being above the water for that whole time - I suspect that's a potential cause of low pre-boil SG.
Anyway, back to stirring. During the first 20 minute rest I circulated outside the malt pipe, and after my first stir I blended in the centre pipe in order to drive water through the mash and bring the temperature closer to the water temperature - I think the mash was around 63 and the water at 65 until that point. (penny just dropped: this is why the default strike water target temperature is 68 when you turn the B40pro on)
I wanted to have quite a bit of water through the centre pipe so that any solids that fell through the screen at the base would be sucked back into the mash and not make it to boil, but I found that the more I circulated through the mash the lower the water level became outside the malt pipe, until at one point the dip tube was sucking in air. Good job I had it set high enough to avoid scorching the elements. I adjusted the balance between circulating around / through, and found that stirring the mash caused the level outside the malt pipe to raise again quite quickly, especially if I stirred low down. Trouble is, I'm not sure if I should have been stirring constantly, every 20 minutes, or not at all, so I kept it to a minimum and only stirred when I thought the water level outside the malt pipe was getting too low, because I didn't want to compact the mash too much and ask for trouble when sparging. In the end I think that translated to some stirring every 10 minutes or so.
Phew - long post. In summary I think I need to:
- Measure water accurately and account for losses in chiller, plumbing, etc.
- Improve my mash technique; maintain 65 ℃ inside the mash, better understand when to rest and when to stir.
- Get a better sense of timing. I think I rushed from mashing to sparging (via a brief attempt at vorlauf) and then from sparging to boil because I was convinced bad things would happen if the temperature dropped too much or if the grain bed got too dry.
Once again thanks to everyone who helped out, I appreciate it very much. Here's how the actuals stack up against the recipe:
![BREWING THERMOMETER STICKERS ACCURATELY MONITOR FERMENTING BEER & WINE LIQUID TEMPERATURES 5PCS HOME BREW SPIRITS WINE LCD ADHESIVE [US]](https://m.media-amazon.com/images/I/311DDjo2X3L._SL500_.jpg)
