Adding water during the boil?

[cassa]

My next batch uses 75% Pilsner malt and I'd like to do a 90-min boil, instead of my normal 60-min, to get rid of some DMS. The extra 30 minutes means more boil-off losses, so I plan to use more water. Problem is that I don't want to take the extra risk of a boil-over.

So, my thought is to add the extra water after 30 min of boiling, bring the wort back up to boiling, and then boil for the remaining 60 min.

Any problems with this? Will it work as well as a full 90-min boil? Should I handle the problem a different way (other than buying a larger kettle)?

In case the specifics matter, I'm brewing 2 gallons of a Saison using a 3 gallon kettle. In my system, I boil off 1 quart every 30 minutes, so the difference between a 60-min and 90-min boil is 1/2 gallon of room for the boil vs only 1 quart of room for the boil.

Thanks in advance for any advice.

--Aaron

 

[Ozarks Mountain Brewery]

first all grain ? or extract, extract you don't get dms like all grain

thats really not going to achieve what your looking for, but its not going to hurt either !. I would suggest getting a bigger pot and doing a full boil with all the water, if possible.

also if all grain and you do a 90 minute boil add it to the recipe editor, then set your mash percent , put the exact boil volume and ending to fermenter in then save the recipe then look at the tools/quick water requirments calculator. there it should say how much water you need

 

[Nosybear]

Aside from the fact that your hop utilization will be almost impossible to predict and you'll get more kettle caramelization (Maillard reactions, actually), I see no problem with your idea. Be sure you boil at least ten minutes to sanitize the water, although when I was doing small batches and diluting directly with our admittedly very good tap water, I had no problems. You may have to do some tests to see how your hops work with the regime.

 

[cassa]

Aside from the fact that your hop utilization will be almost impossible to predict and you'll get more kettle caramelization (Maillard reactions, actually), I see no problem with your idea. Be sure you boil at least ten minutes to sanitize the water, although when I was doing small batches and diluting directly with our admittedly very good tap water, I had no problems. You may have to do some tests to see how your hops work with the regime.

I'm not worried about hop utilization, because my recipe has the first hop additions at 60 minutes, so I'll just put the first hops in after the wort comes back up to the boil and then boil for 60 minutes. Am I missing something?

 

[cassa]

first all grain ? or extract, extract you don't get dms like all grain

thats really not going to achieve what your looking for, but its not going to hurt either !. I would suggest getting a bigger pot and doing a full boil with all the water, if possible.

also if all grain and you do a 90 minute boil add it to the recipe editor, then set your mash percent , put the exact boil volume and ending to fermenter in then save the recipe then look at the tools/quick water requirments calculator. there it should say how much water you need

Sorry, wasn't clear. This is my fourth all-grain batch. I brewed extract 20 years ago and have recently gotten back into it, but with small batches and all-grain because it's more fun for me. A bigger pot isn't in the cards in the short term.

I've already played around with the water requirements in the recipe editor. Given my system and my experience with the previous 3 batches this year, I'm confident about the amount of additional water needed for 90 minutes.

Another option is to just brew a 1.5 - 1.75 gallon batch, but I'd rather brew 2 gallons.

 

[Nosybear]

A more concentrated wort does affect utilization - you'll get lower utilization from the process you describe. It may not be a factor but using the same amount of hops, a more concentrated wort will be less bitter than a less concentrated wort given the same boil time. The answer is simple - use a bit more hops, start at 10% more and see if you get the results you want. Your beers will be darker but that's unavoidable given the concentrated wort.

 

[cassa]

A more concentrated wort does affect utilization

I must be dense, but I don't understand why the wort would be more concentrated while the hops are in it.

With a 2.75 gallon, 90 minute boil, I think I would have 2.5 gallons with 60 minutes remaining (when the first hops go in). With my alternate plan, I'll start with 2.5 gallons, boil off .25 gallons, and then add .25 gallons of water; so, I'll still have 2.5 gallons of wort with 60 minutes remaining. Won't I have the same amount of sugars in the wort, and therefore the same concentrations, in both situations?

I must be missing something.

On the other hand, if the only downsides is that the beer is a little less bitter and a little darker than designed, I can live with that. I can adjust the next time I brew the same recipe.

 

[The Brew Mentor]

Cassa,
What you're planning will be perfectly fine. You may get a slight darkening of the wort but nothing too significant.
If I were doing it, I'd have the additional water hot and as soon as you get past Hot Break, I'd start adding it to the maximum amount I could without boiling over. Another option would be to collect the entire pre-boil amount, and boil it in 2 separate pots for the first 30 minutes and then combine them prior to your 1 hop addition.
Hope this helps,
Brian

 

[cassa]

If I were doing it, I'd have the additional water hot and as soon as you get past Hot Break, I'd start adding it to the maximum amount I could without boiling over.

Sounds like a nice process improvement. I like the idea of being able to add it earlier to reduce the risk of hop utilization issues like Nosybear mentions. I had forgotten that after hot break, my risk of boil over is pretty low anyway.

Thanks Ozarks Mountain, Nosybear, and Brew Mentor for all the wisdom shared here.