Mash Temperatures

[mitchar19]

If I mash in a beer at 154 then drain off into a kettle. If the wort I drain off into the kettle starts to drop below 154, does conversion still take place in the kettle? Is it creating a more fermentable wort if the temperature of the wort in the kettle drops into the upper 140's?

 

[PupThePup]

Conversion is done in the mash tun, not the kettle.

You shouldn't drain your wort unless it passes an iodine test, meaning that it has fully converted.

However, if you were to drain your wort @154, without full conversion, conversion would still be taking place in the kettle until the wort cooled to ~145.

Why would you drain your wort before full conversion?

 

[mitchar19]

No I always wait at least 60 minutes in the mash tun for full conversion. My fear is that if I drain the wort into the kettle and it cools off in the kettle that I'm going to end up with a more fermentable wort than intended.

 

[TopherM]

That's a prime reason to do a mashout. If you mash in a kettle, heat it up to 170F for 10 minutes to stop conversion and lock in your body profile. If you mash in a cooler, you can sparge with 170F water to get the same effect.

The mashout stops all enzymatic activity permanently, so no more conversion post-mashout no matter what the temp. Just make sure you have full conversion prior to the mashout. 60 minutes of a solid mash temp with +/- just a few degrees from start to finish does it everytime!

 

[PupThePup]

No I always wait at least 60 minutes in the mash tun for full conversion. My fear is that if I drain the wort into the kettle and it cools off in the kettle that I'm going to end up with a more fermentable wort than intended.

Not likely as when you sparge with 168+ water the conversion is halted and since you checked that the conversion was complete in the mash tun your pre-boil specific gravity shouldn't change due to minor temperature flucuations.

I've heard of wort being mashed one day and boiled the next, never tried it myself so I can't speak for the results. Liquid/Dried malt extract is just wort that has been continuously boiled to drive off the water (simplified but you get the idea...) leaving the sugars behind.

Brewing is a process and every decision made during that process affects the end result, so it may very well be that your wort specific gravity goes up a tad while cooling and then again while heating, but I don't believe that it would be a significant amount.

Things like fining/hop additions may be more affected than the specific gravity.

 

[Yooper]

That's a prime reason to do a mashout. If you mash in a kettle, heat it up to 170F for 10 minutes to stop conversion and lock in your body profile. If you mash in a cooler, you can sparge with 170F water to get the same effect.

In theory, that's the case. But if the FG is where it should be, then I wouldn't worry too much.

For me, I do mash out when I fly sparge, but I still have my runnings on to heat while draining the MLT. For when I batch sparge, I don't mash out but I use a hotter infusion to get the grainbed to 168 and then also start the first runnings on to boil right away.

So, I guess the answer is "it depends". If you're not starting the first runnings onto boil as the MLT is draining, and it will be held at a while before that, then a mash out is a good idea.

 

[toxdoc49]

I wondered if 154 F mash temperature was high enough. Just asking since I have used higher mash temps. But it probably depends on the style that is being brewed? I suppose the lower mash temp results in less conversion, for lower ABV such as a session IPA.

 

[CascadesBrewer]

I wondered if 154 F mash temperature was high enough. Just asking since I have used higher mash temps. But it probably depends on the style that is being brewed? I suppose the lower mash temp results in less conversion, for lower ABV such as a session IPA.

hmmm...not sure what you are asking about is related to the thread you resurrected...or if you are asking anything...but...

• Higher mash temps (say 158F) create a wort that has more unfermentable sugars which will have a higher final gravity resulting in a lower alcohol beer.
• Lower mash temps (say 148F) create a wort that has more fermentable sugars which will have a lower final gravity resulting in a higher alcohol beer. Due to the lower temps, the conversion takes place slower so it is common to do longer mashes at lower temps.

 

[kh54s10]

Also, anything higher that 158 is getting too close, for my tastes, to the temperature that will stop enzymatic activity and drastically slow or stop conversion.

The highest I have ever mashed was 156. Temperature is also for flavor. Higher temperature is good for malty flavored beers like Stouts, lower temperatures will give you a drier beer, less sweet. I go as low as 148 for APAs and IPAs and the like.

 

[McKnuckle]

To answer your question, if you’re mashing at 154 for a typical hour, you’ll denature most of the beta amylase which is the enzyme that operates at lower temps. Therefore when you drain the wort and it cools, beta will be very minimally active if at all. So no - it won’t continue to convert.

 

[Beerfly]

I've also heard most of the magic happens in the first 15 minutes with today's malts.

 

[kevin58]

The only negative you will get by letting your wort sit in the boil kettle long enough that it cools below mash temps is that it will take that much longer to reach a boil. Nothing to worry about.

 

[toxdoc49]

hmmm...not sure what you are asking about is related to the thread you resurrected...or if you are asking anything...but...

• Higher mash temps (say 158F) create a wort that has more unfermentable sugars which will have a higher final gravity resulting in a lower alcohol beer.
• Lower mash temps (say 148F) create a wort that has more fermentable sugars which will have a lower final gravity resulting in a higher alcohol beer. Due to the lower temps, the conversion takes place slower so it is common to do longer mashes at lower temps.

Thanks that’s what I was wondering about. Makes sense since this is a session ipa recipe.