Oops. Starting mash temp too high!

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The Judge

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Made a mistake in starting my mash and walking away, only to return 15 mins later and see that I forget to reset my temp controller from last brew, and the temp was set to 72C.

Not sure of the side effects of mashing that high for a short period. It's currently dropping about 0.5degree per minute to target of 66C.

The beer is a Belgian Strong Ale, and I will be adding dextrose throughout fermentation to hit target ABV.

Can anyone say what the side effects of mashing above 70C for this duration is??

Thanks.
 
Yeah, temp dropped to 66C in 5 mins. But need to know if there's any impact to the mash - e.g. have the enzymes denatured?
 
Possibly some effect on Beta Amylase, why not add in an extra half kilo of crushed base and mash half an hour longer at your normal sacch. rest.
 
Not sure if it helps but if I overmash (only once though advised another brewer brewing my recipe to do this) - I increase bitterness accordingly.

Rule of thumb is 5 IBU per degree over mash. Mightn't be useful if you've corrected quickly but I reckon even for the minutes for yoy, a minor IBU adjustment is okay.
 
Ok cheers. Increased the saccharification rest time by the 15 mins that it was over temp, and will increase hop additions marginally. Don't have extra base malt unfortunately. Will post any lessons from this brew up in this thread in a month.
 
72 is a bit much, but sounds like it got down pretty quick - I think you'll be fine. Most of the sugars are dissolved in first 20 minutes of mash so just be a bit more vigilant with it. Its pretty easy to get hot water cold, but the opposite is more time consuming :)
 
If anything your FG could be a bit higher, but some extra sugaz can always fix up any drop in alcohol content :ph34r:
 
storeboughtcheeseburgers said:
72 is a bit much, but sounds like it got down pretty quick - I think you'll be fine. Most of the sugars are dissolved in first 20 minutes of mash so just be a bit more vigilant with it. Its pretty easiy to get hot water cold, but the opposite is more time consuming :)
I'm not quite sure what you mean about dissolution of sugars. A good amount of available starch is converted in 15-20 mins but that is quite diffetent.

To the OP- there are two enzymes responsible for saccharification. Your rest at high temps has favoured one over the other. Alpha amylase would be optimised at those temps and works quite quickly to convert starch to long chain sugars which contribute to mouthfeel and body. Beta amylase is capable of converting those long chains into shorter ones but is optimised at lower temps and takes a bit longer.

Yes the denaturing of beta amylase most likely commenced but it is not an instant process. Depending on who you read, beta is fairly rapidly destroyed around 75, alpha around 80. Below those temps, denaturing takes time.
Myself and a few other brewers often mash beers like uk milds at 70 for limited time to get finished beer with lots of body that doesn't attenuate too much. It is possible yours will do similarly depending on how much available beta remained, yeast strain and health, etc.
 
Update:
Took final gravity reading of 1.020.
From the OG of 1.089 that gave me an attenuation of 77.5%.
The Wyeast 1214 Belgian Abbey I used has a range of 74-78%, which is pretty much spot on.

So it looks like that initial high mash temp didn't have too great an impact on the short chain fermantable sugars. But here's hoping to some additional mouthful from those longer chains that might still be in there.

Note: I pitched a massive amount of yeast (probably close to 350-400 billion cells) for a 12 L volume) and it fermented out in about 2-3 days. It was a Belgian so I made sugar additions, and each one fermented out in about 8 hours.
 
Update:
Opened the first bottle of this stuff, tastes mellow and smooth, with a hint of heat from the alcohol. Thought I don't think the ca. 8%v/v alcohol content is there. Seems like a lot of those long chain sugars contributed to gravity but not to EtOH conversion which explains the big body. But really really smooth for only a couple of weeks old. Will put 2 dozen bottles away in the cellar to see how it comes out in 4-6 months.

In all, that super quick mashing at 72C seems like it has had a significant impact on the conversions. Not a disaster but not the intended beer either.
 

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