Need Some Help With My Mash

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Guys I have done my 3rd batch today and once again I had to finish sparging before I got my full volume. I have been doing a hydrometer reading to tell me when its done.

Today I had 2kgs Pilsner Malt 2kg Vienna 2kg Munich to make a 25 ltr batch. But I only got about 22 ltr . I know it is probable simple but you have to learn some how. Can someone help Pleeeease!!!
How much water did you heat? How much did you allow for grain absorption?
I was only going to add about 15 Ltr but I ended up using about 20. Because I had this problem in the past. But it still didn't help
What S.G. were you aiming for? What did you get? What temperatature was the wort at when you took the reading?

Do you crush the grain yourself or have it done at the lhbs?

Its fun asking lots of questions! Not much help though ;)
Do you mean Rubes you are not going to solve my million dollar question?

sg 1010 is and used promash to do the hydrometer tempreture conversion.

G & G did the crush for me.
You know I think I have worked it out and yes I am a D#@k Head, I think I was converting my readings the wrong way.

I don't think so!!!!!!!
I'ts only because I had to start thinking when you asked me questions and then worked it out.

So thanks I guess.
Can you explain what went wrong.Not that I was any help on the chat last night, but if its here then any others that follow might realise they're going down the same way.
I was going to ask if maybe you were sparging too quick and getting channelling where you'll get the water tracking through the grain bed the same way and not extracting any sugars as they had been rinsed through already.

If that makes sense :huh:
Yep I was doing the conversion the wrong way I actually had a long way to go.

When I was converting instead of getting a reading of 1020 @ 60 deg running the conversion it is actually 1036 but I was doing it ass about and getting 1004.

I don't actually know how I did this for three brews in a row. I thing I was so worried about get something wrong with the mash that I rush doing the simple things.

Anyway now I know.
Bigfella, I used to religiously stuff about with hygrometer readings of the run off but finally decided to simply just sparge to get the correct volume in the boiler, then take an SG of the boiler (after a stir) to work out how I was going. Works great for me and I have not noticed any problems with tannin extractoin or any of that kinda stuff. Promash really helps if you set it up as it can tell you exaclty how much sparge water you need to hit your boil volume.

Only time I have payed a bit more attention was on a low gravity beer (1.038) where I thought it was looking pretty clear with 10L to go ... took a readiing and got less than 1.000 @ 70deg! Stopped sparging and just added the 10L to the boiler ... hit the gravity fine.

Food for thought anyway.
I would like to re hash this old post.
I still seem to have the problem of falling sort with my boil amount every time I do a mash.

I 'm using Promash so I know how much grain and water I should be using. I'm still using hydrometer to check the run off and doing the heat conversion with Promash.

Do you think I should just do the run of until I get the required amount and not worry about the gravity reading.

Can people please tell me what is there preferred method.

I have to add that I have don about a dozen batches you would think I could work it out by now.

The important bit you need to know is your efficiency. This is how effective your brew gear and your techniques are at extracting the good stuff out of the grain and into your boiler.

Do an easy pale ale, 100% pale ale malt, aim for a final 1.045 og into the fermenter. Then, use whatever quantity of pale ale grain you had as the starting point for working out your brewhaus efficiency. You can then be all technical and start plugging stuff into brewing software, or, go the simple path and say, "I had 5kg of grain, this gave me a starting gravity of 1.048 in the fermenter before I pitched my yeast, next time I want a 1.040 brew I can use x amount of grain."

Do not worry about what efficiency other people achieve. This often seems to end up as a competition as to who can urinate the highest up the wall. After 10-20 brews, by all means start comparing your efficiency to other brewers. This may highlight a problem you have with your techniques. Many recipes assume that you have 75% efficiency, just scale everything for your brew. The important point is to aim for what your brewery achieves, not what some pencil pushing 1000 all grain brews book writer achieves with their tuned setup.

The temperature conversions of sg can be very hit and miss. Take your sample, put it in a plastic bag, cool it to 20 deg in an ice bath, then do your hydrometer reading.

Some people use the amount of tannins in the runoff as to when to stop sparging. As you get near your expected cutoff point, run about 3 mouthfuls of the wort into a coffee cup (this has a large thermal mass and cools it quickly.) Taste it. Run some off and chill it, take an sg reading. You will soon start picking by taste when to stop sparging. Some people pick this point easier than others. Do not do this when drinking coke, or coffee or beer, this will make your tastebuds less attuned. Do not aim for the sweetness level. The sugars being extracted late in the sparge are the longer chain sugars and do not taste as "sweet" as the shorter chain sugars.

I find I can smell a change in the wort runoff and stop then. A refractometer also makes this step easy.

I do not recommend just sparging till you reach the required volume. If everything is not right, you WILL be sparging tannins into your brew. It is better to go a bit low on expected sg, rather than sparging that extra few points.

Thanks for activating an old thread rather than starting a fresh thread. These questions are very important to have a good background, rather than launching into a new thread and just repeating old stuff.
Thanks P O L, I will do a simple pale ale for my next brew and see just where I stand. Thanks for spending the time and writing a great reply.
There is no magic that says you will reach your boil vol just as the last of your sugars have been washed out of the grain. If you have to top up the boiler and you are still getting your target OG, then just be pleased that your lautering techniques are efficient. It is when it is the other way round and you've reached your boil vol and there is still too much sugar in the mash then you have to worry about your manifold design.
So if I have to add water to the boiler to get the correct OG, it's not a problem.

I really should be paying more attention to my boiler gravity mees think
It's better to add water to the boiler if you're in doubt. Don't let your runnings get below about 1.012 at the absolute lowest.

Once you've hit this stop the runoff. Trying to squeeze a couple more litres out of your grain is a false economy and a good way to get astringent, husky beers. :(

Had the same problem with my first few all grain beers. I used to just runoff till I hit the volume I wanted and got lazy about checking the gravity of the final runnings. Big mistake. :excl:

I stop even higher and just lash out for a little extra grain. My cutoff is usualy about 1.020, particularly for lighter coloured beers. For pale lagers I'll stop the runoff even higher at or about 1.025+.

Life is very easy for mashers who can get hold a refractometer. :super: Makes measuring gravity a piece of piss. Filling a hydrometer jar, cooling and taking readings, particularly towards the end where the gravity drops rather quickly a bit of a hit and miss affair.

Warren -

As POL sez, if U sparge to the correct vol, U might be getting the wrong flavours (tannin = bad). :(

Mate, it's all practice. May I suggest U keep some DME on hand to top up. So U lauter first, then top up to the required volume, then add DME to bring the sg up to the mark.

Yeah, I know it's not "all-grain", but sometimes U need to exhibit flexibility, and with such a piddling amount of DME, there prob won't be a detectable difference in the flavour.

"My preferred method" by Seth :p
If you brew a 1.045 25 IBU brew, there is plenty of leeway. If it is 5 sg points either way, there is no need to use some DME to top up with.

If you do feel the need to adjust the og higher, tap off some of your wort, say a litre or two, dissolve the DME in this, and put the solution back in the boil. This can be done during the boil, no later than 15 minutes before flameout. So 25 minutes from flameout, do the DME addition.

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