Rest between mash and boil

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yochris77

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What would the possible implications of not immediately transferring the mash to boil?

In an attempt to avoid death by SWMBO I had to walk away from brew after mash complete. Tun (cooler esky) has a well fitting lid on it with minimal head space. Grain has been removed.
 
Generally not much. Depends somewhat on time spent before boiling, temp/time reached of final mash, storage of wort preboil and final desired results. You want a general assurance or a breakdown of enzymatic activity?

I have (and know others who have) mashed, stored and boiled the next day. Not my usual or recommended practice but can be employed in a pinch if you understand what can go wrong and how to reduce/avoid.
 
I regularly mash at night then boil the next morning-night and have never had any noticeable negative effects. Once I got 10 minutes into the boil and had to turn it off to tend to a grumpy toddler, first round of hops were in, restarted the next day and it was a cracker. It's a great way to brew With 2 kids and keep the wife happy.
 
I regularly mash at night then boil the next morning-night and have never had any noticeable negative effects. Once I got 10 minutes into the boil and had to turn it off to tend to a grumpy toddler, first round of hops were in, restarted the next day and it was a cracker. It's a great way to brew With 2 kids and keep the wife happy.

Nice dog Mitch.
Is it a Greyhound or Whippet, or something else?
 
Mash temp was 66 for 60 mins. Sparged at 75 then stopped. It is destined to be an Irish red.

Thanks for the replies. I am feeling relieved. [emoji106]
 
Nice dog Mitch.
Is it a Greyhound or Whippet, or something else?
Haha, it's a whippet, we'd love a greyhound but we don't have the space. That picture is pre kids and I can't figure out/have time to update it.
 
Not best practice, there are a couple of reasons.
One is that unless you have mashed out - that is to say heated the mash or wort hot enough to stop all the enzyme activity (call it 80oc) the enzymes will keep chipping away and will change the fermentable profile of the beer.
The other being that you haven't sterilised the wort, even grist that has been heated to the same temperature as the wort is still full of live lacto (as anyone who has left malt in the tun overnight will know). Without heating to a boil the odds of having an infection go through the roof.

If something happens and you cant stay to finish the job, OK shit happens you do what you need to, and you might save the brew by getting back to it as soon as you can. As a way to plan your brew day, its not a very smart idea.
Mark
 
I've frequently done overnight mashes to achieve a drier beer, and it was quite common in the 1970s as recommended by Dave Line in his Big Book of Brewing. However anything longer than say 9 hours would definitely be stretching things. Haven't done one for a long while, if I had to do it again but as an emergency situation, I'd heat to mashout, say 78 degrees and then lag it up for the overnight rest.
 
I've often done overnight mashes and like what it brings to the table, beers attenuate that bit better and I gain a little efficiency.

However, Mhb comment holds true for me on the longer term. I left a beer 24 hours in the urn including bag and grain and ended up with a slight lacto sourness in it.

It was a Saison with 3724 and was awesome but it would have been a disaster with another beer.
 
Mash temp was 66 for 60 mins. Sparged at 75 then stopped. It is destined to be an Irish red.

Thanks for the replies. I am feeling relieved. [emoji106]


By temp/time of final mash I mean what was the highest temp it hit at the end (or during) and for how long. If it was 66 and you added 75 deg water, final temp would be somewhere between 66 and 75.

MHB referred to 2 things that are pertinent to this point - wort sterilisation (function of temperature and time) and fermentability/mash profile (also function of temp and time). If you were to hit 80 (actual mash bed/wort) and hold for 10 mins, then stored wort in a well sealed container or even brought to a boil and racked to nc cube, you'd vastly reduce the risk of infection or changing profile. Even an improperly sealed cube after a fully boiled wort enters it, can result in badly infected wort so the storage bit is also important.
 
Thanks guys. I don't think it would have got sterilized. Can't imagine it would have gone over 75 for long enough. It sat in tun for 6 hours maybe? Then straight to kettle for boil. Everything else went well. Fingers crossed.
[emoji482]
 
Good read.

Forgot to add that when I overnight, I set the urn to hold temp.

When I had the lacto slightly soured mash, I turned it off after overnight and let it cool over the day.
 

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