90 min mash

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
When the kids were littler and I had less time I used to overnight mash so I could get everything done quicker in the morning. I had much better efficiency than a normal 60 min mash. I wouldn't say I had higher fermentability as my beers generally stop at 1010 whatever I do. I think they possibly had more body to them, but wouldn't say that was scientific ly proven.
Not "scientifically proven" you say, but a very good illustration of what's goin' on (or at least confirm my opinions ... I'm not "scientifically proven" either).

Many plant enzymes just act faster and faster with more heat. Up until the point the heat destroys them. So, the optimum temperature is the one that the job can be done the fastest before the enzyme expires. For beta-amylase that is relatively cool, alpha-amylase is much more resilient. So when overnight mashing, most beta-amylase (which is creating maltose) is destroyed before you go to bed, whereas alpha-amylase ("randomly" chopping up starch and longer chain dextrin into shorter chain dextrin) goes on, finding the hard-to-reach starches and thereby increasing efficiency, but not necessarily fermentability (producing more dextrin, although most - not all - brewery yeasts these days can ferment short-chain dextrin, or "malt-triose").


I was mentioning "Chavallier" barley malt earlier. Mashing longer to give, what appears to be, lower beta-amylase amounts time to act. I should have added I keep the temperature lower too (62-64C) to also give the beta-amylase more chance to do its job.
 
Interesting. What do you call the low side - 62 degrees C? Received wisdom seems to suggest that 66C is the usual mash temperature, but the recipe I have borrowed for a Brugse Zot clone calls for a mash at 62. Does that mean I'll get better efficiency at that slightly lower temperature?
Can you share the recipe? I enjoyed it when I had it at the brewery and wouldn't mind having a go at brewing it.
 
Can you share the recipe? I enjoyed it when I had it at the brewery and wouldn't mind having a go at brewing it.
Yes, Brugse Zot and the brun version are my favourite beers and I have been to the Halve Maan brewery many times where you can enjoy it unfiltered straight from the lagering tank! This is my recipe adapted from someone else's clone. I do BIAB method but do suffer from poor efficiency (55%) no matter what I try, hence the grain bill and final volume are adjusted to hit around 6.0 -6.2% ABV based on that efficiency. You may well have a better technique and will need to adjust for better efficiency. I substitute Golden Syrup for clear Candi sugar syrup as it is a fraction of the price and there is no noticeable difference. 90 minute mash in the bag, 10 minute dunk sparge, and 90 minute boil. Hope it works for you. Here's the link: Permission Error | Brewer's Friend
 
Yes, Brugse Zot and the brun version are my favourite beers and I have been to the Halve Maan brewery many times where you can enjoy it unfiltered straight from the lagering tank! This is my recipe adapted from someone else's clone. I do BIAB method but do suffer from poor efficiency (55%) no matter what I try, hence the grain bill and final volume are adjusted to hit around 6.0 -6.2% ABV based on that efficiency. You may well have a better technique and will need to adjust for better efficiency. I substitute Golden Syrup for clear Candi sugar syrup as it is a fraction of the price and there is no noticeable difference. 90 minute mash in the bag, 10 minute dunk sparge, and 90 minute boil. Hope it works for you. Here's the link: Permission Error | Brewer's Friend
 
I drink a lot of Bathams, bottle and draught. I’ve done GW’s recipe many times on a 60 min mash. If you are looking for a very close interpretation of the original, my humble opinion is that a 90 min mash is not needed
 
I’ve done GW’s recipe many times on a 60 min mash. If you are looking for a very close interpretation of the original, my humble opinion is that a 90 min mash is not needed

FV:
Yeah, agreed, thanks to all who replied. I brewed this a couple of years back with a 60/60 mash and boil. We used Holdens yeast and it was very close to draught and very very drinkableathumb.. still not sure about boiling cabbage for an hour though:vomitintoilet:
 
I know I'm late contributing here, but just in case someone looks back at this in future...

If you're using a longer mash time to boost beta-amylase action (more fermentable wort, drier finish in the mouth) then remember to keep the temp low because beta-amylase irreversibly degrades very fast above 61ºc. Don't make the temp too low though, otherwise the starches in the grain won't dissolve into the wort ('gelatinise') so the enzyme can reach them athumb..

It's useful to know that the reason beta-amylase works significantly slower than alpha-amylase is because it can only process the long chain starch molecules by clipping off simple sugar molecules one at a time from the end of the chain. That's why it gives you such a fermentable wort, because you end up with a lot of simple easily fermentable sugars.

In contrast alpha-amylase can break the links of the starch molecules at any point along their length, which means you end up with a higher proportion of complex un-fermentable sugars as well as the simple ones. If you continue mashing for an extended time then the alpha amylase can break down the complex sugars a bit more, but it takes time and the alpha amylase does wear out eventually.

The combination of alpha and beta amylase working together works really well, because the alpha chops up the long chains giving the beta more 'ends' to work on. But in practice it's actually quite hard to get both enzymes working at the same time because the beta burns out pretty fast (ie. 5-10 mins) at the temperatures needed to get the alpha working. So IMHO if you're mashing at normal temps (66ºc plus) then once you're 20mins into the mash you might as well take the temp up to 68-69ºc in order to boost the alpha activity, as the beta will be fully denatured by then.

Alpha vs Beta graph.jpg
 
All that alpha and beta is past my pay-grade! :D

But because my method is crude and basic, I always do 90 mins mash FWIW, and generally get around 68-72% BHE, so happy with that.
 
Back
Top