mash temp too high, can I let it cool and then start timer?

Had an error in my water measurement (too much water) and my mash temp after adding the grain and stirring is 158 instead of 154 F. I was thinking of just letting the mash cool to 154 F and then start my timer. Anyone have an opinion on this fix it process?

Add a little cool tap water.

Normally I would add water or ice cubes but the water level is 1/4 inch from the top of the kettle after adding in the grain. I assumed that the 5 gallon water bottles purchased from Walmart would hold 5 gallons but they actually hold more like 5.75 gallons and this is the source of my error.

Chemistry doesn't care when your timer starts. It starts doing its thing right away. Higher temps will speed up the denaturing process of the proteins and cause the mix of enzymes to do different things at different speeds. I'd get the temp down within 10 minutes and if letting it sit will drop the temp within 10 minutes, you need to work on insulating your mash tun.

msa8967 said:

Normally I would add water or ice cubes but the water level is 1/4 inch from the top of the kettle after adding in the grain. I assumed that the 5 gallon water bottles purchased from Walmart would hold 5 gallons but they actually hold more like 5.75 gallons and this is the source of my error.

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Probably late now but i would have dumped some wort and added cold water.
(Next time maybe)

SkiNuke said:

Chemistry doesn't care when your timer starts. It starts doing its thing right away. Higher temps will speed up the denaturing process of the proteins and cause the mix of enzymes to do different things at different speeds. I'd get the temp down within 10 minutes and if letting it sit will drop the temp within 10 minutes, you need to work on insulating your mash tun.

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This was a brew in the bag recipe in my 10 gallon pot. I kept gently stirring the wort and it dropped to 154 F within 10 minutes. I'll see how it will taste in 6 weeks.

bazowie said:

Probably late now but i would have dumped some wort and added cold water.
(Next time maybe)

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I will keep this in mind if this happens again. It seems to be a very practical solution which may be why I didn't think of it at this time.

It is always a good idea to keep some boiling water and some cool water on hand when mashing in a cooler to make temperature adjustments. Monday I was shooting for 148 and hit 158. Took a temperature reading and I dumped cold water immediately.

Don't wait to start the timer. The mash is working anyway. You can cool it with cool water as suggested or if you are using Beer Smith or similar, plug in the temp and possibly use a shorter mash time. It would change the result a little bit though.

msa8967 said:

This was a brew in the bag recipe in my 10 gallon pot. I kept gently stirring the wort and it dropped to 154 F within 10 minutes. I'll see how it will taste in 6 weeks.

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You're most likely fine then. I was under the assumption it was a traditional mash.

The wort was meant to have a SG of 1.052 and volume of 5 gallons but came in at 1.041 with 6 gallons instead. I split this between two 5 gallon buckets (actual maximum volume) and then boilled 2 lbs of extract to add 1 lb to each bucket to try to bring this closer to where it needed to be.

If you had boiled off the extra gallon, you would have been darn close to your target - 1049 instead of 1052. Sounds like you just need to measure your water better and you'll be in good shape.

I had volume issues, then I bought a gallon measuring pitcher from a restaurant supply store for $15 and haven't had any more problems.

Another thing I do, and this may not be of great help to anyone but I am going to throw it out there regardless, is I will typically:

1. Heat my Strike Water to about 2-3 degrees over what BeerSmith or any calc tells me I should.
2. Add it to my tun and stir until I am about 1-2 degrees above my Strike Temp, usually doesn't take much.
3. Once I dough in, following this method, I am typically a couple degrees high on my mash temp so I leave the lid off my tun and stir like the dickens to a) break things up and get a good mix and b) release some of the heat in the mash and bring it down to my mash temp.

After trying a couple times to follow the temps I was given and missing my mash temp and playing the juggling water game to hit the right temperature and throw my water to grain ratio off, I find overshooting by a few degrees and stirring to cool things off works the best. If you overshoot each step by about 3 degrees you never have to spend more than 5 minutes stirring to get things where they should be. And what is 5 minutes in the scheme of a 60+ minute mash.

Just my 2 cents. Happy Brewing!

QuercusMax said:

If you had boiled off the extra gallon, you would have been darn close to your target - 1049 instead of 1052. Sounds like you just need to measure your water better and you'll be in good shape.

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I agree. I use a hop spider (hop sack) for adding my hops to the boilling wort. I wonder if knowing that I needed to boil off an extra gallon at the end means I could remove the hops and boil until I reach 5 gallons w/o changing the hop profile (IBUs) of the beer.

msa8967 said:

I agree. I use a hop spider (hop sack) for adding my hops to the boilling wort. I wonder if knowing that I needed to boil off an extra gallon at the end means I could remove the hops and boil until I reach 5 gallons w/o changing the hop profile (IBUs) of the beer.

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You wouldn't extract any more IBUs but you would most likely boil off more flavor and aroma. Not sure this is backed up by science but I believe that is what would happen since it would further cooked down whatever hop oils have been extracted at that point.

I think you could probably leave the hops in. The difference in bitterness between 60 and 90 minutes is pretty minor, from what I understand. A 90 minute boil will give more caramelization, so you might want slightly more bitterness to compensate. Sounds like a good experiment.