is a 4.5 F drop in mash temperature (after an hour) significant?

[Elysium]

We mash at 154.4 for 60 mins and by the end of this 60 mins, the mash temp drops to 149.9 F. I am wondering if in any ways this will affect the final product badly?
Any thoughts on this?

By the way.......we do BIAB. It is relatively difficult to cover the pot in something, because it tends to be too hot from the direct flame.

 

[rnm410]

I'd say no, your are still in the 150 F range for conversion. What are you mashing in?

 

[freisste]

It may have an effect, but it is likely a small one. Not something is worry about too much. The biggest thing is that your mash will convert starches pretty quickly (I think in ideal cases in less than 15-20 minutes, but don't quote me), so your temperature drop from the beginning to the point where starches are converted is more like 1.5deg. Later, you will make the wort a little more fermentable, but probably not much. Carry on; RDWHAHB.

 

[Cyclman]

It is always a range to convert, not a digital, exact number.

 

[jro238]

I disagree a bit with some of the other comments. Will a 4F difference make good beer into crappy beer? Hell no. Could it make great beer into good beer? Absolutely.

It will make it more difficult to hit your target final gravity and can definitely cause some headaches when trying to fine tune recipes (especially for beers like large belgians or IPAs that really need to hit their target FG).

I use a normal chest cooler for a mash tun and have found that it will lose somewhere between 3 and 5 degrees over 1 hour if left uncovered. When I cover it with a space blanket and a couple of towels I can hold temperature within 1 degree over an hour. It is a really easy (and cheap) way to eliminate this variable.

 

[butterpants]

I lose less than 1 degree/hr in my triple refletix wrapped keggle. I think you just need to insulate more.

 

[billsea]

I was wondering the same thing. I recently listened to a Beersmith podcast (can't remember which one) and someone said that the conversion from starch to sugar takes place in the first few minutes of the mash. This would be the critical phase to form the right kind of sugars. The rest of the mash time is used to extract the sugar from the grain. This means that only the first few minutes are really important. This is way different from what I have always thought. Not sure what to believe now.

 

[butterpants]

How can you convert starch to sugar if it hasn't been made soluble and extracted yet?

 

[billl]

4 degrees doesn't sound like much, but it is huge in brewing. Mashing at 152 would be a medium bodied brew. Mashing at 156 will be a meal in a glass.

Are you sure about your starting temp? You need to wait for the tun and grains to stabilize before you get an accurate reading. eg if you put 154 water/grain mix into a cold tun, it will drop temp pretty quickly the first 5 minutes or so while the tun warm and then hold pretty much constant after that.

 

[billsea]

How can you convert starch to sugar if it hasn't been made soluble and extracted yet?

Just passing along what I heard hoping that and expert might chime in and set me straight. I wish I could remember which podcast it was. But, starches can be converted to sugar in the grain. That is how they make crystal malt to the best of my understanding. They take the grain just after it has been malted and is still wet. Then they let the enzymes work a little longer to convert the starch into sugar in the grain. Then they roast the grain and that caramelizes the sugar.

 

[Clonefan94]

I disagree a bit with some of the other comments. Will a 4F difference make good beer into crappy beer? Hell no. Could it make great beer into good beer? Absolutely.

It will make it more difficult to hit your target final gravity and can definitely cause some headaches when trying to fine tune recipes (especially for beers like large belgians or IPAs that really need to hit their target FG).

I use a normal chest cooler for a mash tun and have found that it will lose somewhere between 3 and 5 degrees over 1 hour if left uncovered. When I cover it with a space blanket and a couple of towels I can hold temperature within 1 degree over an hour. It is a really easy (and cheap) way to eliminate this variable.

I agree with this. I've found the magic treatment for this is to throw one of those old style furniture blankets, the padded, quilted kind, over the top of it. I brewed a couple times this winter, where my garage temps were in the mid 30s and I lost only 1/2 a degree in the mash over an hour.

Without it I have lost up to 3.5 degrees.

 

[Queequeg]

I have a cooler mash tun. I wrap the ball value in bubble wrap, then a few fleece blankets. I then cover the whole tun with a quilt. I get about 1 degree F or 0.5C temp loss

 

[Pie_Man]

Don't sweat about your beer, it will be fine. I have heard of some craft breweries losing 8-10 degrees during the mash by design.

As you probably want as much control over your mash temp, I would preheat your tun. The simple way to do this is to add strike water into your empty tun that is about 5 degrees F higher than needed and cover. The water will cool fairly quickly without the mass of the grains and your tun will heat up to maintain mash temps better. As mentioned, wrapping the outside of the tun will also help.

 

[Elysium]

4 degrees doesn't sound like much, but it is huge in brewing. Mashing at 152 would be a medium bodied brew. Mashing at 156 will be a meal in a glass.

Are you sure about your starting temp? You need to wait for the tun and grains to stabilize before you get an accurate reading. eg if you put 154 water/grain mix into a cold tun, it will drop temp pretty quickly the first 5 minutes or so while the tun warm and then hold pretty much constant after that.

Well, we take quiet some time to finish the dough in. I pour the malts in, while my mate is stirring. I think it is pretty much accurate what we normally measure (talking about the temp.)

 

[Queequeg]

^^ when I dough in I leave about 2 litres of the mash water out, then take the temp and add the remaining 2 litres as a combination of 90C, 20C or strike temp water so that I can dial in the mash temperature progressively.