Recipe Critique

[timmi9191]

Slow the flow of the sparge water into the malt pipe

 

[TheWiggman]

Hang on... the Robobrew looks like a budget Braumeister in that there is no need to sparge if you do a full volume mash. A lot of brewers do anyway for a few extra points (as do BIABers).
I'm not knowledgeable with this system. What volume do you mash in at? Say you're doing a 23l brew with 5kg of grain, do you start by heating ~28l of strike water and then do minimal sparging/rinsing to 'top up' to your desired pre-boil volume? Of would you start with 20l and use 8-10l of sparge water?

 

[PoN]

For 5kg of grain, the general consensus is a 20L mash in.

If the grain absorbs 5L of water then you will have about 15L of wort when you are ready to sparge, for a 19-20l (probably the upper limit of brew size with this seystem) brew you want a pre boil volume of around 26-27Litres so sparge volume ends up at around 12 Litres.

The robobrew is designed to sparge.

I have never tried a full volume mash before, so do you think I should try mashing with 25L or so of water and only do a small sparge?

 

[droid]

you may have to be mindful of pH but maybe doing it in a bag changes that

 

[TheWiggman]

Considering you're getting efficiency issues (this seems to have gone off topic sorry) you haven't got much to lose by varying your process. In a single-vessel system there is no need to sparge per-se but it's a common practice to get a few extra points out of the brew. If you mash in with too small a ratio (i.e. <1.5l/kg) you will run into more trouble that if you have a high ratio. There are exceptions of course but for a standard ale, full volume is 100% fine.
I would meet it halfway and do exactly as you say. Though looking at post #17 you sound like you've done quite a lot with the exception of recirculation (which isn't necessary if others are getting different results with the same process). I would still challenge how water pH could have that much of an impact on efficiency. 5% maybe, but 25%... can't see it.

 

[droid]

just to clarify - my reference to pH is about it's affect on the profile of the beer not eff

 

[contrarian]

You need to think about this more like BIAB than 3v brewing where your sparge is to get desired volume more than for efficiency.

You can try a longer mash, around 90 minutes is what I normally use. Also when you do sparge what water temp are you using?

Definitely try a few % of acidulated for lighter beers. From what you have said this should help.

I'm sure you can improve the efficiency of your system without adding more vessels. Or at least get your light beers up around the same level as your darker beers.

 

[PoN]

Water to grain ratio in this system is a lot different to a 3v system due to the malt pipe. I run with 4L/kg which is probably way too much in a 3v set up, but because your grain is contained in a smaller malt pipe in the robobrew the mash thickness is still quite thick and would probably be similar to 2.5L/kg in your standard mash tun.

Sparge water temp is 75 degrees.

So i am going to try a fuller mash with my next brew with minimal sparge. As you said it's essentially BIAB except the bag is the malt pipe.

 

[timmi9191]

isnt there a dedicated robobrew problem and guideline thread??

 

[PoN]

Yeah. This didn't begin as a robobrew thread though.

 

[Rocker1986]

I use a robobrew

So any lighter coloured beers I struggle to hit 50% total efficiency(mash efficiency around 60%) Darker beers I hit 60% total efficiency (mash efficiency 70%)

So far I have tried:

Different sources for grain and finer milled grain
Recirculating every 10-15 minutes
Longer mash time
Stirring the mash every 10-15 minutes
Using more water in my mash
Using less water in my mash
Different mash temperatures
Larger grain bills
Smaller grain bills

The red section could be an issue too. This is just from my own experience of brewing BIAB with an urn, but I found finer milled grain didn't work as well. My efficiency jumped quite a bit when I started milling the grains a lot more coarsely, so that might be worth a shot as well. Haven't had any issues with the water at my place so far; I generally hover around 75% brewhouse efficiency for most batches.

 

[PoN]

Ok so I brewed this today with a slight adjustment

2.5kg JWM Ale malt
2.5kg JWM vienna
.5kg Wheat
.15kg caramalt

1g gypsum
1ml Lactic Acid
(decided to go with less additions for the first time with water chem)

Tested Ph 15min into mash and it was 5.5. Albeit with test strips but whatever.

Went with a 75min Mash @66 and 15min Mash out @ 75

Also went with a 23L: mash instead of 20L with a 9.5L sparge insted of a 12-13L sparge.

So far my mash efficiency is at 64% so a good 10-15% higher than previous lighter malt brews.

There is fairly significant improvement, but still below where I want to be.

 

[timmi9191]

Glad you have found some improvements, but I think you could still achieve better eff.

If you are so inclined, brew the same beer again. Whats the max volume you can mash in the robobrew? Try a max volume mash for 90 mins.

Then drizzle the sparge water through the malt pipe as slow as possible. Try a saucepan lid or similiar to push down on the grain and squeeze the last of the wort from the malt pipe.

Get that Ph down a few more points. Use the Bru'n water spreadsheet, this should get Ph right on and also imporove the water profile for the beer type.

Try it and see what the eff is.

Just my $0.02

 

[PoN]

Well i did 23L today could easily do 26-27L mash, that would only require a 5L sparge.

I do plan on adding more salts and acids to my next brew, Bru n water did seem pretty accurate with where my mash ph would be at. Just wanted to test it out this time and not overshoot it.

 

[drsmurto]

Ok so I brewed this today with a slight adjustment

2.5kg JWM Ale malt
2.5kg JWM vienna
.5kg Wheat
.15kg caramalt

1g gypsum
1ml Lactic Acid
(decided to go with less additions for the first time with water chem)

Tested Ph 15min into mash and it was 5.5. Albeit with test strips but whatever.

Went with a 75min Mash @66 and 15min Mash out @ 75

Also went with a 23L: mash instead of 20L with a 9.5L sparge insted of a 12-13L sparge.

So far my mash efficiency is at 64% so a good 10-15% higher than previous lighter malt brews.

There is fairly significant improvement, but still below where I want to be.

What was the pH before you added the gypsum and lactic acid?

 

[PoN]

Not sure. Added it just before I added the grain. Bru n Water estimated it at 5.8 without any salt or acid additions.

 

[Rocker1986]

It would be worth measuring the pH more than relying on software estimates. I've never bothered with mine because my efficiency is fine, although I have noted an increase in efficiency when using a small amount of acid malt in pale beer grists.

In any case, I agree with Timmi, 64% mash efficiency is very low, this could be improved another 20% easily. My mash efficiency is usually in the mid-high 80s without doing anything spectacular.

 

[Ducatiboy stu]

Personally, I would get your efficiency up before playing with water.

There are so many things that affect eff %, and water is only a small part ( a very small part )

I never treated my water ( except the odd occasion when doing a Burtonised English Bitter ) and could get 80% with 3v AG without touching my water, which was mostly rain water

 

[drsmurto]

Not sure. Added it just before I added the grain. Bru n Water estimated it at 5.8 without any salt or acid additions.

This i don't understand. How do you know if you have a mash pH problem if you don't measure it?

 

[Ducatiboy stu]

This i don't understand. How do you know if you have a mash pH problem if you don't measure it?

I dont think he has a pH problem. He has a process problem

Get the process sorted before even think about water. Dont wag the dog