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Time for the harder questions. Why?

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ilv4xn

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I have a couple batches of wine under my belt. Jumped from wine to AG brewing. Legged my first stout last week and my second batch is currently in a secondary ready for keg this weekend. My questions are
1. How dose mash temp affect grain?
I know too hot = tannins
What about 140deg or 130 for 90 min vs 151

2. With wine you degas to vent sulphur compounds that formed during ferment. Why don't we off has beer?

3. More grain = more alcohol
Depending yeast of course
 
lower mash temps = more fermantable wort.

there is nothing to degass in beer, you aerate with O2 at the start and the yeast makes CO2 which you need for carbonation anyway.

more grain = more alcohol but it also depends on efficiency.
 
I have a couple batches of wine under my belt. Jumped from wine to AG brewing. Legged my first stout last week and my second batch is currently in a secondary ready for keg this weekend. My questions are
1. How dose mash temp affect grain?
I know too hot = tannins
What about 140deg or 130 for 90 min vs 151

2. With wine you degas to vent sulphur compounds that formed during ferment. Why don't we off has beer?

3. More grain = more alcohol
Depending yeast of course

1. Certain enzymes are more active at certain temperatures. Mashing at 130 degrees would mean that the enzymes that break up proteins are active, but not the enzymes that change starches to sugar, so a 130 rest wouldn't "work" because it's not warm enough to really activate the temperatures for a saccrification rest. The most important enzymes are beta amylase and alpha amylase, active from about 140-165 degrees. Temperatures of 140-150 favor beta amylase, while higher temperatures favor alpha amylase. A good "Sweet spot" that uses both is 150-152. A higher temperature will favor a thick, dextrinous wort (due to more long-chained sugars resulting) while a lower temperature will favor a thinner, drier beer in the end.

2. I've only been making wine about 20 years so a "sulfur venting step" is news to me. Maybe that's something very new, or very old? I've never heard of that.

3. Well, yes. More sugars= more alcohol, as long as you don't exceed the yeast strain's alcohol tolerance.
 
If mashing at 152 I a good thing. Then why sparge at 170? Wouldn't this bring out the tannins?
I was under the belief that off gassing wine was to remove co2 as well as other ferment gasses. Am I wrong in that as well??
 
Sparge no hotter than 170°F, as husk tannins become more soluble above this temperature, depending on wort pH. This could lead to astringency in the beer. Sparging is one last rinse to extract sugar from the grain.
 
If mashing at 152 I a good thing. Then why sparge at 170? Wouldn't this bring out the tannins?
I was under the belief that off gassing wine was to remove co2 as well as other ferment gasses. Am I wrong in that as well??

The sparge question has been pretty well answered, I think. The mash makes the sugars, and the sparge rinses them out. That's pretty simplistic, but by the time you sparge, conversion is complete and then it's time to extract the wort from the grain. Rinsing the grain ("sparging") gets as much as possible of the sugars from the grain.

I don't usually degas wine, except for kit wines that are rushed to bottle. And the only purpose for that is to get rid of excess co2 in a hurry.

Occasionally, the wine is stirred at the beginning of fermentation (not kit wines, but fruit wines). That's for several reasons: to break up the "cap" formed by the fruit that sticks out and could try out and mold, to get some oxygen into the wine (again, only at the very beginning of fermentation), and to release some trapped co2. But releasing the trapped co2 is a secondary benefit, as the yeast will just produce more as fermentation goes on.
 
Besides making the sugar easier to get off the grain (as already mentioned) the hotter sparge also denatures the enzymes leaving the mash profile in tact
 
1. Certain enzymes are more active at certain temperatures. Mashing at 130 degrees would mean that the enzymes that break up proteins are active, but not the enzymes that change starches to sugar, so a 130 rest wouldn't "work" because it's not warm enough to really activate the temperatures for a saccrification rest. ......................

Not quite true. Starch converting enzymes are active at 130 F, just not at their maximal rate. All of the various enzymes we take advantage of in mashing are active at any temperature above freezing and below their denaturing temperature. Keep in mind that these are the same enzymes that the seed uses during germination, and barley is a cool climate crop, so all of the enzymes we take advantage of during the mash are fully active at 50 - 60 F. It just takes ~ 10 days for the seed to convert all of the starch to sugars for the developing embryo to use for it's growth. Then photosynthesis takes over

What is correct is that the various enzymes are acting at different rates. The goal in mashing is to pick a temperature (or temperatures) that creates the ideal environment to produce the wort profile (sugars and proteins/peptides) that you want. As the others mentioned, mashing at lower temperatures creates a more fermentable wort resulting in a lower Final Gravity, more alcohol, and a lighter body. As you increase the mashing temps, The FG and body go up and the ABV goes down
 
what do you mean by "degas to vent sulphur compounds"

I will have to go check my wine book as it sounds like I might be wrong. But I was under the impression that CO2 as well is other compounds sulphur being one of them became trapped in soultion. Tho is why you swirl your carboy or use a degassing rod I a drill prior to bottling. Having used the swirl method I know that a lot of gas is trapped even after 6 months or so. I know 6 months is not a long age for wine but hey I need my carboys for beer and more wine.
 
In brewing beer, the natural sulfur compounds end up as Dimethyl Sulfides (DMS) during the boil and are driven off with the water vapor. That is the primary reason you shouldn't keep the lid on when boiling wort.
 
To touch on the sparging thing again, keep in mind that sparge water pH plays an important role in tannin extraction. However, if the temp is below around 170, it's not a problem. So for simplicity they recommend sparging at or below 170.

But, think about Decoction mashing, where the actual mash (grains and wort) are boiled and added back to the mash to raise the temp of the mash. Why does the boiling temp not cause tannin extraction? Because the pH is low enough to prevent it. The 170 guideline allows people to sparge without worrying about whether the pH is dropping due to the acids from the grains being rinsed away. The more you sparge, the closer the pH gets to the water's pH, which is way too high to prevent tannin extraction at high temps.

I think it was Kai who had a nice little experiment in sparging with colder water. I think the result was that it didn't significantly harm the extraction of sugars. I have sparged at around 150 because I was lazy and that was what my sparge water was when I wanted to sparge. I don't' recall an issue with efficiency.
 
To touch on the sparging thing again, keep in mind that sparge water pH plays an important role in tannin extraction. However, if the temp is below around 170, it's not a problem. So for simplicity they recommend sparging at or below 170.

But, think about Decoction mashing, where the actual mash (grains and wort) are boiled and added back to the mash to raise the temp of the mash. Why does the boiling temp not cause tannin extraction? Because the pH is low enough to prevent it. The 170 guideline allows people to sparge without worrying about whether the pH is dropping due to the acids from the grains being rinsed away. The more you sparge, the closer the pH gets to the water's pH, which is way too high to prevent tannin extraction at high temps.

I think it was Kai who had a nice little experiment in sparging with colder water. I think the result was that it didn't significantly harm the extraction of sugars. I have sparged at around 150 because I was lazy and that was what my sparge water was when I wanted to sparge. I don't' recall an issue with efficiency.

How do I calculate efficiency?
 
That is a difficult answer to give. There are threads about it and many of the books have it wrote down.

It's just comparing your gravity against a theoretical gravity with a given grain bill and mashing technique. You have to measure volumes very carefully and do the mash, then compare against what your potential would have been. People in labs crush different types of grains extremely finely and perform a mash to come up with a maximum amount of fermentables for that pound of grain.

You compare against this theoretical maximum. You have consider things like deadspace (wort left in the grain or mash tun) as part of it as well, so you are not just calculating the mash efficiency, but an overall brewhouse efficiency.

Having a consistent efficiency is important to being able to hit the Starting Gravity you are aiming for. Some people like to "Hot Rod" their system so they can get the highest efficiency they can, and while that may be fun for them, I personally don't think think it's important for making great beer. You can save a bit of money by using a small amount less grain, but IMO 79-80% or so efficiency is fine. Anything less than 70% should not be hard to improve. Once you start going over 90 it might be very difficult to improve, and there may be a downside in flavor in the finished beer.

So what I mean to say in my last post is that using water that is a bit colder than normal doesn't lower the efficiency much compared to what you would normally get.
 
How do I calculate efficiency?

(Potential sugar in your grain in points above 1.000 x pounds of grain / volume of water in gallons)

So, if you're using:

8 pounds of grain with a potential of 1.035
2 pounds of grain @ 1.028
and 5 gallons of water your max potential =

(35 x 8) + (2 x 28) / 5 = 67 or a potential of 1.067.

You measure what you end up with - and compare it to the maximum theoretical - so in this case let's say you got 5 gallons at 1.047 - that would be an efficiency of 70% (47/67).

make sense?

It's all simple algebra.
 
"How do I calculate efficiency?"

Easy answer - use one of the online calculators. Plug in your grain bill and then scroll through the efficiency numbers until you hit your starting gravity.

Yes, there are lots of technical things behind it and it might not even be your "true" efficiency, but that doesn't really matter. As long as you are consistent in process, you can plug in that efficiency number for your future brews to predict their OG. If you were a trying to make a profit making beer, maximizing your efficiency would be critical. If you are just trying to make tasty beer, consistency is sufficient.
 
.

What is correct is that the various enzymes are acting at different rates. The goal in mashing is to pick a temperature (or temperatures) that creates the ideal environment to produce the wort profile (sugars and proteins/peptides) that you want. As the others mentioned, mashing at lower temperatures creates a more fermentable wort resulting in a lower Final Gravity, more alcohol, and a lighter body. As you increase the mashing temps, The FG and body go up and the ABV goes down

Is there a chart or a list that shows this relationship. What temp range are we talking?
Mashed at
140 my beer will taste?
150 my beer will taste?
What kind of ABV difference will there be?
 
Generally you will mash at between 149 and 160.

At 149 your beer ought to be drier and have more fermentables, therefore a higher ABV.

At 160 you will have more sweetness or maltiness and more mouthfeel, with a lower ABV.

I highly suggest you go to www.howtobrew.com and have a look at that website. It's the "free" version of John Palmer's book on brewing. He's got a newer edition out now, but there is still plenty you can discover on that site. He talks about alpha and beta amylase and some other stuff that might help clear it up some.
 
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