Topping off during boil

[gyllstromk]

I have a slightly smaller kettle than I'd like. It's the bottleneck of my process, that ultimately dictates my batch size. The actual volume of the kettle is OK, but of course, after an hour boil of evaporation and shrinkage, it gets smaller.

I was thinking of solving this problem by topping off throughout the boil. Is there anything wrong with this?

 

[Walker]

nothing wrong with it. You could also just wait until the end and top it off in one shot.

 

[bsdx]

If you want to avoid stalling the boil with cold water, you could boil small amounts of water and add those. Cold water really kills a boil. Bringing a small amount of water to boil on the range top takes very little time.

 

[gyllstromk]

Is tap water considered sanitary enough to add without boiling, after the boil is complete?

 

[frazier]

I wouldn't add a lot of tap water at the end. Bsdx had a good suggestion.

I keep a jug of Ice Mountain handy, should I need some water at the end.

 

[gyllstromk]

One potential advantage to the cold top off is the cooling power. I wonder if I can start a smaller water boil alongside the wort boil, then kill it quickly and let it cool for the remaining 45 minutes of wort cool, then dunk it in the wort at the end.

 

[Walker]

If you're topping off 4 gallons with 1 gallon of tap water, I'd bet you are at a very LOW risk for any problems. Just add the tap water before you start your regular chilling and give it a few minutes to sit there. The 4 gallons of >200*F wort you added the top-off water too will clean anything out of the water.

 

[iijakii]

Yeah I have the same problem. I can only do half batches because of my 20qt boil pot. I've never wanted to top off though because I'm always right on my aimed SG.

 

[Special Hops]

Is tap water considered sanitary enough to add without boiling, after the boil is complete?

When I did extract I always topped off the fermenter with water straight out of the tap.

 

[rexbanner]

Keep in mind that whatever you add needs at least 15 minutes of boiling to sterilize. So, don't add any water past that point. Otherwise, feel free to.

Also, don't use tap water unless you run it through a brita or add some campden. Tap can contain chloramine which does not boil off and inhibits yeast.

 

[Walker]

Keep in mind that whatever you add needs at least 15 minutes of boiling to sterilize. So, don't add any water past that point. Otherwise, feel free to.

LOADS of bacteria will die in temps over 110*F. Others need more heat, but 180*F is hot enough to kill almost everything.

 

[joel6615]

Have some preboiled water ready for your brew day. Problem solved.

 

[rexbanner]

LOADS of bacteria will die in temps over 110*F. Others need more heat, but 180*F is hot enough to kill almost everything.

True. Back when I did partial boils I used to mix my extra 2.5 gallons of water straight in to the wort, and I never had any bad brews. Nowadays I just prefer to err on the side of caution.

 

[weirdboy]

Also keep in mind that if you are "topping off" to 5 gallons while boiling, you still aren't really getting 5 gallons into the fermenter that way because of thermal expansion.

 

[rcrabb22]

Also keep in mind that if you are "topping off" to 5 gallons while boiling, you still aren't really getting 5 gallons into the fermenter that way because of thermal expansion.

The "accepted normal" shrinkage from hot to cold is 4%. 1 gal (128oz) * .04 = 5.1 oz. Add a gal and a cup.

FWIW - I measure my water for brewing at cold tap temperatures, 48F winter to 69F summer

 

[Walker]

The "accepted normal" shrinkage from hot to cold is 4%. 1 gal (128oz) * .04 = 5.1 oz. Add a gal and a cup.

The whole volume in the kettle shrinks when cooling, so you would need to make sure you top off to 5.0 * 1.04 = 5.2 gallons... so add a gallon and a quart.

but we're really splitting hairs here, aren't we?

 

[rcrabb22]

The whole volume in the kettle shrinks when cooling, so you would need to make sure you top off to 5.0 * 1.04 = 5.2 gallons... so add a gallon and a quart.

but we're really splitting hairs here, aren't we?

Yes, Yes we are

 

[Scimmia]

but we're really splitting hairs here, aren't we?

Isn't that what we do here?

 

[Walker]

unfortunately, yes... it happens more than it needs to.