What is your preboil volume?

[HighHops]

I always tend to stop sparging after collecting 27L for the boil for a 5 gallon batch. Just wondered if this is about average, because I never get more than 75% efficiency, but am worried about extracting tannins from the last runnings.

[Normski]

Hi HighHops
Pretty much the same for me. I used to do a lot of testing and cooling and measuring and always came to about the same.
So I now start with 32L. I boil with around 24-25L and top up after the hot break to keep it at around 25-26l. To end with around 23L in the FV.

[Wolfy]

30-32L pre-boil is usually what I aim for, then usually end up with 22-24L into the fermentor.

[Horatio]

30-32L pre-boil is usually what I aim for, then usually end up with 22-24L into the fermentor.

+1 for me when doing a 23l batch.

[weiht]

I start with 29l of wort and end with 23l after 90m boil. But I'm thinking of going for another 2 litres as I do lose abt 2-3 litters to hops n protiens left behind in the kettle, esp on those really hoppy brews. I try to aim for 23l into the fermenter, or at least 21l so I end up with a full keg.

I do add bottled water if i lose alot to evaporation or I overshot efficiency(no more than 1.5l to avoid diluting the hop aroma n bitterness)

[mark4newman]

Hi

I start with about 42 litres in the boiler, to end up with about 25 litres in the fermenter (90mins boil).

[weiht]

Hi

I start with about 42 litres in the boiler, to end up with about 25 litres in the fermenter (90mins boil).

WOW!!!!

Do u sparge all the way for the 42l or u collect until 1008 and top up with water? I see that 25L is into the FV, how much do u loss in the kettle? I hate to sound rude but i think the boil may be a little too vigorous. Once boiling, it doesnt have to boil full throttle and just need a rolling boil as u wanna avoid kettle caramelisation (unless thats something u want in ur brews). This is why many breweries prefer steam to direct fire to have a more gentle and controlled boil... thats alot of evaporation

[mark4newman]

Hi

I batch sparge. Normally I start with two lots of 24 litres. Then divide this into two equal run offs, and give the grain about 6 litres

I suspect kettle losses are no more than a litre or two.

My boil may be a "little" more vigourous than most, but it seems to work fine by me. I like the results that I get. Also I don't get caramalisation, apart from the time I wanted it, with a scottish 60/

[Kev888]

I tend to work backwards to get my estimates; it varies on the quantity of hops of course but for a typical beer I lose about 15% in the boiler through evaporation, the hops retaining some, and dead space - so (to use round numbers) for a brew length of 85L I'd want to collect 100L pre-boil.

I worked out through trial and error that I normally get a total 'brew house' efficiency of about 75% (or more like 70% in wheaty brews) so thats how I determine my grain bill for the desired gravity. Say it was around 22.5kg; I mash at 2.0L/kg (I'd like it slightly looser but my MT isn't big enough), so the mash will use about 45L of liquor and the sparge must therefore make up the remaining 55L needed plus losses of about 20L to the 20kg or so of grain retaining it, so around 75L in total for the fly sparge.

I do measure the gravity of the last runnings but generally they seem okay without me needing to worry about it, though maybe it would be closer to the mark if I was trying for low gravity brews or managing higher extraction efficiencies.

Cheers
Kev

[gregorach]

I suspect kettle losses are no more than a litre or two.

You might want to double-check that - you can easily lose more than that to hop absorption.

[GrowlingDogBeer]

I reckon you lose 1.5 litre of wort per 100g of leaf hops.

I also lose about 10% over the course of an hour which for me is 5 Litres.

I usually start my boil at 50 Litres to end up with 40 Litres in the fermenter (I use a lot of hops).

[mark4newman]

Hi Dunc

You might want to double-check that - you can easily lose more than that to hop absorption.

You might well be right, I have never measured what the hops absorb, although I do add on a couple of litres to the brew if I am doing a hoppy brew (Ie 250grams or more)

[HighHops]

Sounds like I am under sparging, stopping at 27L in the kettle! I probably lose 4-5L on the boil and then usually top up the kettle after cooling with another 4-5L of preboiled cooled water to 25-26L again in the kettle to allow for hop absorbtion. This also helps get the temperature down that last few degrees for pitching temp. I was worried about extracting tannins by over sparging. I will have a look at this next brew and push it up to 30ish L in the kettle. It's probably costing me brew efficiency.

[Brotherton Lad]

I fly sparge and usually end up with about 32l in the boiler for 90 mins.

This gives me 23l for the fermenter and depending on efficiency, hops etc another 2 to 4l which I ferment in a demi-john.

I like to do it this way, because the demi-john gives me a control brew. I then usually keg from the fermenter and bottle from the demi-john. I look upon the bottles as a little present to myself and a reserve supply.

[GrowlingDogBeer]

Sounds like I am under sparging, stopping at 27L in the kettle! I probably lose 4-5L on the boil and then usually top up the kettle after cooling with another 4-5L of preboiled cooled water to 25-26L again in the kettle to allow for hop absorbtion. This also helps get the temperature down that last few degrees for pitching temp. I was worried about extracting tannins by over sparging. I will have a look at this next brew and push it up to 30ish L in the kettle. It's probably costing me brew efficiency.

Get yourself a refractometer then it's really easy to check the gravity of your runnings as you sparge.