Sparging Question

[Ste_Mulv]

Hi all,

I am looking for some help with sparging. I am going to rinse the grain bed with a shower of hot liqour, however I am uncertain about how much sparge liqour to use. I have read that I should stop sparging at 1010 and some places say 1020.

First question is how do I measure the sparge run off? do I sparge to a separate container and wait until the sparge liqour alone reaches 1020 or do I take spot samples of the sparge liqour and wait until the spot gravity reaches 1020?

Finally, what gravity should I be aiming for?

Thanks for your time team beer!

 

[serum]

You need to take spot samples. Sparging will slowly dilute the wort in the mash tun and you want to stop before it goes too far and starts extracting stuff you don't want.

What I tend to do is shove a hydrometer tube under the mash tun tap from time to time to check the gravity.

One thing to bear in mind is that the wort will be hot so you need to correct your readings. There are calculators to do this. I used a guide when starting and it said that, provided the sparge is at 75C, you don't want the wort gravity to go lower than 0.998. I tend to get my target amount of wort before this anyway so it's never been a problem.

You can roughly work out how much wort you need by working out the dead space in your boiler and also how much water you'll lose by boiling and hop absorption. I tend to heat up more water than I think I'll need and just stop once I've got enough for the boil.

 

[Ste_Mulv]

Hi serum,

Thanks for your reply, much appreciated.

I read your reply last night and spent a great deal of time today using the info you provided to try to size my brewery system.

I am trying to work out the size for my MT and Cu.

Reading around, there are some guides that advocate the gravity of the wort leaving the cu should be higher than the pitching gravity, to allow you to water down the wort (with treated liquor) to get more beer from a smaller copper size. In a similar vein the gravity of the wort leaving the mash tun will be diluted by the sparge run off.

With that in mind, I am trying to work our how to relate the gravity calculated from the recipe to the pitching gravity.

All my all grain brews, I have sparged until the boiler is full, and not measured gravity of the sparge. I am now looking to work out the relationship.

So how does the recipe gravity relate to the pitching gravity?

I have worked through the process in a lot of detail and assuming that extraction does not drop off as the ratio of malt to mashing liquor, I assume this high gravity mash, then diluted down will give a large quantity brew with a smaller mt and cu.

Is there a normal ratio of mash liquor to sparge liquor that is used to reduce the sparge gravity to 1020 ish?

Finally, as the sparge liquor rinses the grains, is there a linear decease in the gravity of the run off?

Any advice on general brewery sizing would also be awesome!