No worries. Let me re-phrase and try again. We know you’ll want to start the boil with 6.5 gallons so that 90minutes later you still have 5 gallons of wort remaining to turn into beer.
After mashing your strike water (5.3 gallons) with your 17lb grain, you will drain the wort from the mash. You should get in the ballpark of 3.2 gallons of wort. However, we need to get 6.5 total so 3.2+X=6.5, where X=3.3 gallons of sparge water needed. It’s this 3.3 gallons that you’ll put through your grainbed to sparge with. Once you’ve done that you’ll have 6.5 gallons of preboil wort to start your boil. Does that make more sense? If not, no worries, I’ll try again ;D
As for the 3.2 first runnings quantity: I assume 0.125 gallon grain absorption per pound of grain: 17x0.125=2.125 water loss due to absorbtion. So 5.3 gallons of strike minus 2.125 gallons absorbed equals 3.175 gallons of first runnings (I rounded and called this 3.2 gallons).
Confusion clarification: I’m not overly familiar with the grainfather so perhaps I’m not understanding how the sparging takes place on that unit. My assumption was that after mashing you would lift the basket and lock in place above the BK, AND THEN you would pour the sparge water through the grainbed (and those runnings would also end up in the BK eventually). If I’m not correctly understanding how the GF functions then please let me know and I’ll adjust my thinking.
Question about strike water temperature. I understand adding room temp. grain will lower the temperature of the strike water, so strike water is initially higher than target. The target being 150F for 60 minutes. Once the grain is added to the strike water of 166F and temp begins to drop, do I monitor and adjust until the temperature levels off at 150F?
Don’t worry too much about that, the temperature drops fairly quickly. I would encourage you to take detailed notes about this, so that next time you brew this you can make adjustments for your system, so you can predict accurately the mash-in temperature. I.E., amount of grain and water, and temperature of both in the mash.
I do worry a bit about mashing in too warm, and possibly destroying some enzymes. I like to target a couple of degrees low, and after a short rest, let the system regulate to your setpoint. I’m not sure I’ve ever noticed a problem when missing my mash-in a couple of degrees high, but it just kinda makes sense.
I’ve mashed beers at 162 and even as high as 164 and still got good conversion. if you are aiming for 150, and you hit 155 you MIGHT notice a slight difference in body.
The rackers.org calc is a pretty good resource for simple strike water temp determination. If you’re wary of it’s calculated temperature then you could err a little on the cooler side (say 2 degrees cooler), and see where you end up. I always found it easier to reduce mash temp (using ice or a frozen water bottle) then to increase temp, and much quicker too.
Rackers indicates that for a mash ratio of 1.25, targeting 150 mash temperature, and using grain at my room temperature (72F), the strike water should be 165F. If you’re worried of resting too hot then try reducing a couple degrees (163F), and see where you land - then adjust next time based on how this time worked out (that last part is something to get familiar with because it’s the nature of this beast :D)
I assume the recirculating pump can be switched on as soon as the grains are mixed and there are no clumps?
The rackers.org site has some nice calculations available…Rest calculation- at what point do you take the current temp? Once grains are mixed? Looks like it provide you with a water boil quantity to add to get to the targeted mash in temp?
I couldn’t really say about the pump since I don’t use a pump and don’t know well enough about the GF to give any recommendations. I would imagine that information is listed in the manual somewhere - hopefully.
In regards to Rackers Rest calc: you would ideally take the temperature right before adding boiling water to hit your next rest for the most accurate calculation. This would be used in a circumstance where, say, you were resting at 150 and wanted to go up to 160 for 20 minutes, it could tell you how much boiling water you need to add to make that mash temp adjustment (keeping in mind they’re working off of 212F as a boiling point; if you’re high enough in elevation then it may require additional water due to a lower boiling point) - caveats
if you’ve got the ability to manipulate the mash temp with a recirc then there isn’t really any danger of hitting a slightly too low strike temp.
My comment was more to remove stress about overshooting.
Basic structure here:
~145-149 - a lighter body, greater attenuation, longer mash time for full conversion
~150-155 - Medium body, medium attenuation, medium mash time for full conversion
~156-162 - Greater body, lower attenuation, shorter mash time for full conversion
however, I generally concern myself with three mash temps
~148 for light bodied, or very high gravity beers
~155 for medium bodied, crisp but malty medium gravity beers
~162 for extra body in low gravity beers or straight up thickness in bigger beers.
And I’ve found that malt has so much diastatic power these days that temp matters a lot less than it used to. I’ve mashed the same recipe at 153 and 165 and gotten identical results.
okay, I was able to find a retail brew shop with most of my needed ingredients. I did forget to write down DME for yest starter and also dextrose.
Question about the hop additions and use of dextrose. When I read a recipe it will something like-
Hop abc @ 60min
Hop abc @ 10 min
Hop abc @ FO, steep 30 min
Dry hop…4 days…
So, add hops at the start of the boil until completion, add hops 50 minutes into the boil until flame out. At Flam out, steep hops for 30 minutes. Sound right?
Dextrose. At what point is it added to the brew and what might a ratio be? Tsp/gal
Dextrose can be added at any point from the boil to just past high Krausen in the fermentation. It is highly frmentable and will dry out and raise the alcohol lev l in your beer. Depending on the style, it could be used up to a pound or so in a 5 gallon recipe. I prefer to use it sparingly. I will use it in Belgian beers and very light American styles.
