49 replies to this topic

[chuck_d]

Ah - the good ole intertubes e-penis posturing. Oh you guys...

I mean, that's good info for directing your searches to learn more. That's why I posted. But yeah, I like to nerd out.

[3rd party JKor]

Chuck, care to find us the reaction rate constant for denaturation of β-amylase at 165°F?

[Stout_fan]

Grains to water.I find that you get more doughballs if you go water to grain.BrewBasser

Yea, surface tension is a PITA.Actually I've gotten doughballs going grain to water as well.But only if I add the grain too fast.And if you don't ever see doughballs, you aren't milling fine enough.However, I underlet and add water to the bottom of the tun.Turn on the pump and pump over the premeasured volume from the HLT.Nary a doughball. The grain just wicks it right up and hydrates perfectly.Capillary action is your friend.All batches converted just fine.

[3rd party JKor]

Here's a paper (looks like a college level Bio lab report) on temperature dependence of Amylase. Not very in-depth, but it does show that the amylase (no distinction between alpha and beta in the paper) is completely denatured at 80°C (176°F) almost instantly.https://www.associat...lase.html?cat=5

[chuck_d]

Chuck, care to find us the reaction rate constant for denaturation of β-amylase at 165°F?

I struggle with chem honestly, it'd probably easier if my bookshelf was stacked with chem books instead of math, physics and computer ones.

[MtnBrewer]

What if they bring in a new pitcher in the middle of the at-bat? It happens.

That's the beauty of batting from both sides of the plate at once. It doesn't matter.

[3rd party JKor]

That's the beauty of batting from both sides of the plate at once. It doesn't matter.

add the grains with your left hand, and water with the right?

[MtnBrewer]

add the grains with your left hand, and water with the right?

Pretty much. I've found that I don't really have to "add" the water. Because of gravity, it will add itself so all I have to do is add grains while the tun is filling up.

[AiredAle]

My take on the cautions about "shocking enzymes" with too hot water is based on the knowledge that when the enzymes are dissolved in water they will denature at too high a temperature. This temperature sensitivity is different for enzymes that are still in the solid state in the ground up malt. After all, pale ale malts, for example, are dried and roasted at temperatures up to 220 F with no serious loss of enzymatic power. Since the enzymes are in the undissolved, dry state when grain and water are mixed, they should suffer no damage in the few minutes that it takes to get the grain and water mixed and at temperature equilibrium. Only after the grain is hydrated do the enzymes start to dissolve and become vulnerable to denaturation at lower temperatures.

[3rd party JKor]

My take on the cautions about "shocking enzymes" with too hot water is based on the knowledge that when the enzymes are dissolved in water they will denature at too high a temperature. This temperature sensitivity is different for enzymes that are still in the solid state in the ground up malt. After all, pale ale malts, for example, are dried and roasted at temperatures up to 220 F with no serious loss of enzymatic power. Since the enzymes are in the undissolved, dry state when grain and water are mixed, they should suffer no damage in the few minutes that it takes to get the grain and water mixed and at temperature equilibrium. Only after the grain is hydrated do the enzymes start to dissolve and become vulnerable to denaturation at lower temperatures.

Good point. There are many heat and mass transfer processes going on. The enzymes not only have to become dissolved in the water, but they must do so fairly quickly to be exposed to temperatures more than a few degrees above the mash temperature. Further, the grains themselves are at room temperature when added. Even if the kernel becomes completely wetted at the instant it contacts the water, the temperature within the kernel is significantly below the strike temperature at that time. The moral of the story is that it's not that easy for the enzymes to be exposed high temperatures at mash-in. Although, it would be interesting to see data for β-amylase activity using the two different methods.