Raising mash temp

[Martin the fish]

The Durden Park recipe's all call for a long mash and then raising the mash temp after for a while. No other home brew recipe's recommend this. Why are the DP recipes like this? Please don't say 'it's cos how they used to do it' cos OBVIOUSLY i know that.

Or is it really because no-one knows and thats how they used to do it.

I don't like doing things just cos thats how it says in the book. I'd rather ask why they do it like that if i don't understand-and i don't. I'm happy to brew like that but i'd really like to know why i am.

[Andy]

It's a "mash-out" step to stop the mash conversion by killing off the enzymes. Some people do this as a matter of course, others don't bother. You can do it by adding a quantity of very hot liquor to the mash.

Edit: With the Durden Park recipes it's also probably in there to thin out the mash a bit ready for the sparge such that the sugars can be run off easily. The Durden Park method does call for stiff mashes.

[Martin the fish]

So i could do this on my normal brews?

Whats the advantage?

[steve_flack]

Whats the advantage?

You denature the enzymes so they can no longer convert the mash. By the time your mash is over the starches should be converted to shorter chain length sugars. The process of degrading these into more fermentable sugars can still continue though gradually making the beer more fermentable and drier. If you do a mash out then both processes are halted - possibly leading to a fuller bodied beer.

Also raising the temperature reduces the viscosity of the mash making it easier to sparge.

[Andy]

So i could do this on my normal brews?

Whats the advantage?

You could.

I think that if you were after a beer with "body" then the mashout stops your "body" sugars (dextrins) continuing to get converted into fermentable sugars (maltose) after the mash has ended.

[Martin the fish]

Wow.

Thanks guys. That now makes sense to me. It's definately something i'm going to try on my next brew.

I never thought brewing would be so much fun and such an interesting learning curve. Wish i'd started 20 years ago

[flytact]

I like to do a mash-out if I can get the temp up with less than 2 gallons, any more than that and it becomes a pain.
Also, if the mash is already thin then I skip it.

General all grain question/statement: Are todays grains getting more and more modified that all the "old" ways of mashing are becoming obsolete, making it easier for us?