90min vs 60 min boil - from a practicality standpoint

[Bassman2003]

I have been changing and learning a lot regarding the boil - length, intensity and the overall role it plays. Overall, shortish and low intensity is where it is at. There are a lot of homebrew dogma sticking points like the need for a vigorous boil or 60min vs 90min & DMS. Basically my view is that the boil damages the wort, so you want to limit that damage. If you boil the snot out of wort for 90 minutes, there is nothing magical that will happen other than beat the wort up by overexposing it to thermal load.

DMS is a tricky topic as many do not even taste it. But, a lot of the threat of DMS is taken away with sound process leading up to and after the boil. I would recommend research on the entire chain of SMM formation through DMS as it is not really what I came to learn over the years in the homebrew world. Basically, DMS is not an issue in a 60 min boil. Dimethyl Sulfide

A lot of the folks on podcasts are pointed towards the commercial world, so their practices are not on the same scale as homebrewers. Boiling is an area where we have an advantage in not needing so much energy. So my advice is 60min and aim for ~5% - 8% evaporation. And chill as quickly as you can.

 

[CascadesBrewer]

More of a related question to the shorter mash/boil time. Do you need to make any special adjustments in BeerSmith when crafting the recipe, or does software automatically adjust when you change the mash and boil times?

I don't do 30 minute mashes myself, but I have seen evidence that might mean a few points lower efficiency. If you normally get 75% efficiency, but the short mash drops you down to 73%, you would have to update that value in the software.

As long as you have the boil off rate set as a "per/hr" rate (vs a fixed amount) then BeerSmith calculates the boil off rate and reduces the calculated strike water volume. Note that it does not stop you from entering hops with a "60 minute boil" even though you are only going to boil for 30 minutes.

Moving to a 30 minute boil reduces the amount of strike water which could (should?) lower my efficiency a little. I have not noticed this. It could be that with full volume mashing BIAB, the slight difference in water does not have an impact. Or it could just be small enough that I don't notice. I could see this having more impact with a fly sparge process.

 

[CascadesBrewer]

I’m not trying to be argumentative. I just wonder how they used to do it before extract.

I am not sure what the max gravity value for runnings from an all-grain batch would be. I would be curious what would come out of a no-sparge 1 qt per lb mash.

I did a full volume mash BIAB for a Barleywine and came in at 1.100. I brewed a 1.118 Imperial Stout with BIAB plus a sparge step. I think both of those batches were 60 minute boils with a 1/gal per hour boil off rate. I calculated the Barleywine to be 1.8 qt/lb (so fairly thin) with around a 70% overall efficiency.

 

[VikeMan]

If I put 100 lbs of grain in a big mash tun and 100 quarts of water (1qt/lb) I would get more wort but not higher gravity. To get higher gravity I would need to use less water in the same amount of grain right? 1 qt/gallon is some pretty thick mash. At some point the grain will just absorb water and not give it back any wort. How thick can one really mash?

I’m not trying to be argumentative. I just wonder how they used to do it before extract.

Yes, you'll use less total water per pound of grain, causing mash efficiency to drop with each increase in grain bill size. But as that happens, OG is still increasing. The magic behind this is that all of your lautered sugars/dextrins are going into the same volume of wort. And that wort volume is always a part of your total water volume.

I would recommend experimenting with @doug293cz's spreadsheet if you need a demonstration.

ETA: I make no claims as to overall cost effectiveness. Just talking theory. Also, yes, you'll reach a point where the thickness of the mash becomes a problem. But you can reach RIS/Barleywine OGs before that happens.

 

[doug293cz]

Yes, you'll use less total water per pound of grain, causing mash efficiency to drop with each increase in grain bill size. But as that happens, OG is still increasing. The magic behind this is that all of your lautered sugars/dextrins are going into the same volume of wort. And that wort volume is always a part of your total water volume.

I would recommend experimenting with @doug293cz's spreadsheet if you need a demonstration.

ETA: I make no claims as to overall cost effectiveness. Just talking theory. Also, yes, you'll reach a point where the thickness of the mash becomes a problem. But you can reach RIS/Barleywine OGs before that happens.

The spreadsheet.

Brew on

 

[doug293cz]

I am not sure what the max gravity value for runnings from an all-grain batch would be. I would be curious what would come out of a no-sparge 1 qt per lb mash.

I did a full volume mash BIAB for a Barleywine and came in at 1.100. I brewed a 1.118 Imperial Stout with BIAB plus a sparge step. I think both of those batches were 60 minute boils with a 1/gal per hour boil off rate. I calculated the Barleywine to be 1.8 qt/lb (so fairly thin) with around a 70% overall efficiency.

The max pre-boil SG for a no-sparge mash @ 1.0 qt/lb mash thickness, 1.037 average potential, 4% grain moisture, and 100% conversion efficiency is 26.9°P or 1.1147 SG.

Brew on

 

[CascadesBrewer]

The max pre-boil SG for a no-sparge mash @ 1.0 qt/lb mash thickness, 1.037 average potential, 4% grain moisture, and 100% conversion efficiency is 26.9°P or 1.1147 SG.

Interesting. It is a little lower than I would have guessed, but it makes sense. So really, anything above 1.110 will require a boil to concentrate the sugars, or an addition of sugars.

 

[VikeMan]

Interesting. It is a little lower than I would have guessed, but it makes sense. So really, anything above 1.110 will require a boil to concentrate the sugars, or an addition of sugars.

Luckily, most worts are boiled, so it's not like something special necessarily has to be done. With @doug293cz's no sparge, 1 qt/lb, max conversion example, 6 gallons @ 1.110 boiled down to 5 gallons (fairly average boil off, I'd say) becomes 1.132 post-boil.