Step Up Temperatures?

[telp]

This has probably been asked around many times but reading some other threads made me think to ask this. I attempted a step up mash on my last BIAB brew on a gas range. It took about 10 minutes to get from one temperature to the next one.

For a 60 minute mash, do I count the time it takes to get up to the next temperature as part of the 60 minutes, or should I 'pause' until I get to the next temperature.

Thanks

 

[RM-MN]

The enzymes that convert starch to sugars work at a specific temperature range with beta amylase working at the low end of the range and alpha amylase at the upper end. These ranges overlap somewhat. The enzymes are denatured fairly quickly at temperatures above their range but not immediately (I can't find just how fast).

I did a couple of experiments to see how fast conversion occurs using iodine as the reactant which turns blue if starch is present. with my grains milled very fine for BIAB, I found no evidence of starch remaining within 2 minutes. That may not mean that the beta amylase wasn't still working on making shorter chain, more fermentable sugars but it does hint at how fast the reaction is. Since you will be ramping up the temperature through the range where beta amylase is active first before the alpha amylase even starts, how fermentable will your wort become? I don't know the answer to this. It has been stated that beta amylase works slower than alpha but just how much slower is never stated that I can find.

That whole mess I just posted never answered your question, did it? I think the answer you were looking for is that the clock stops while you are bringing the wort temperature up and starts the 60 minutes when you reach your target temperature.

 

[telp]

I don't think it did...but it was very interesting, and I did not know that information either. Half the reason I started brewing was for that technical side so I do love learning, so thank you for that !

For my last brew, the initial mash temperature was 125º for 15 minutes, then stepped up to 145º for 15 minutes, and then 163º. My question was when stepping up from 125ª to 145º and then to 163º, do I count the time it takes to get up to each temperature as part of each of those time slots? For instance, after 15 minutes at 125º do i bring it up to 145º and then start the next 15 minutes, or do I found the time it took to get to 145º as part of the next 15 minutes.

 

[RM-MN]

Since the enzymes you want to work on the grains have a very specific temperature range that they work in I think that you have to start the clock when you reach that temperature. During part of the temperature ramp up the enzyme for the lower temperature will still be active for a little while as the mash temperature goes up past its upper limit but the next enzyme of interest doesn't start until you get within its temperature range. If you overshoot its range I think that enzyme is done so you can't go back down and get more activity from it.

 

[telp]

Since the enzymes you want to work on the grains have a very specific temperature range that they work in I think that you have to start the clock when you reach that temperature. During part of the temperature ramp up the enzyme for the lower temperature will still be active for a little while as the mash temperature goes up past its upper limit but the next enzyme of interest doesn't start until you get within its temperature range. If you overshoot its range I think that enzyme is done so you can't go back down and get more activity from it.

Thank you RM-MN. That was kind of what I was thinking, but it's good to get a more definitive answer.

 

[telp]

And then I guess a followup question, will the longer mash temps be bad, or will it not really effect it?

 

[FortRock]

Holding your mash 30-45 mins between 140 - 149 will produce very fermentable sugars which will result in a lighter body, dry beer. 150- 158 will produce less fermentable sugars and result in a fuller body with some residual sweetness. If you want lighter body, drier, higher alcohol, mash longer in the 140-149 range, if you want the opposite, spend more time in the 150-158 range. Or you can keep it at 152 for 60-75 mins and be somewhere in between. Your choice.

If you do a targeted 2-step mash, you can probably get away with 60 mins total time for both. If you do a single step mash, then I'd go for 75 mins since both enzymes are not in their 'ideal' range and will take longer to do full conversion.

I wouldn't over do the mash time though, you may end up pulling out tannins and other off flavors from the beer. Most of the starch will be converted to their various sugars after about 60-75 mins total time. You can heat to 168 to get the wort to drain better, but never go higher than that or you will start pulling tannins out of the grains.

All of this assumes that the PH of your mash is in the 5.0-5.6 range-which it usually will be. (Unless you are brewing a stout with soft water, or a pilsner with hard water).

I personally consider the mash timer as ticking when I'm in the mash temp range. Even if I'm heating through.