Sparge Water Temperature Understanding

I need some help concerning sparge water temperature. I am new to AG, and the learning curve is really steep right now.

I understand that if my sparge water is too high, I will extract tanins and other things that I don't want. I also understand that it is ideal to get the mash to 168F to stop the enzyme action. My question is why do you NEED to stop the enzyme action?

Hypothetical situation: If I mash for 60 minutes, and my sparge lasts another 60 minutes, and I sparge at 160F, how is that any different that mashing for 120 minutes (which I have read is not abnormal).

I have done a lot of reading, and may have covered this, but I can't seem recall seeing this covered. Thanks for the help. -John

The words you're using are leading me to believe you're fly sparging. In any case, I don't know anyone that mashes for 120 minutes unless it's a multi-rest mash schedule. Getting the temp up to 168F also helps with efficiency because the sugar becomes more soluable. In a fly sparge, you do this by infusing a small amount of boiling water before the vorlauf/sparge. It's called a "mashout.

I am fly sparging, and the disolving sugar makes perfect sense.

If you hit your mash with boiling water to mashout, you know exactly when your mash time ended. I suppose if your sparge was really consistent you could duplicate it from batch to batch but mashing out is probably easier.

You don't leach out as many tannins (etc.) if the pH is low, so if you really have to heat the mash up (which also leads to extracting nasty flavors) you may as well do it when the pH is in your favor.

I am a little worried that if I put boiling water on the mash that I will extract tanins. I realize that the entire mash will not be up above the critical temperature, but it will be in a localized area. I would expect that I would be extracting the tanins in this localized area. And once they are in solution, I assume they stay that way, and end up in the wort.

At worst case, if I have a cooler sparge, I will have a lower effeciency, but no tanins. Am I on track here, or am I way off. I am sure this has been discussed, so I apologize if I am beating a dead horse. I have done a search on mashout, but have not run across these specific issues yet.

BTW, I am using a cooler for a MLT, so I cannot add supplemental heat after the mash.

You start stirring right after you add the 200F+ water so it equalizes quickly. No need to worry.

There are three factors that affect tannin extraction.
There is the sparge temperature, the pH of the wort during the sparge, and time.
You will always get some tannin extraction during a sparge, and this is acceptable. What you want is to avoid excess tannin extraction.
As the sparge temperature increases, you will tend to extract more tannins, but this is not usually a problem until the sparge temperature exceeds 168F. It is therefore advisable to keep the grain bed down to this level.
As the pH of the wort increases, tannins become more soluble. Assuming that the temperature is below 168F, you will get very little tannin extraction if the pH is below 5.6 You are not likely to get excess tannins (unless you get the spare temperature too high).
The third factor is time. The longer you sparge, the more tannins will be dissolved. This is not usually an issue with batch sparging, but can be with fly sparging (which takes a lot longer).
I always mash for at least 60 minutes. (It takes that long to heat my sparge water).
With low temperature mashes (150F or lower), I will extend the mash up to 90 minutes if an iodine test shows that the mash has not completed. I've never needed to go beyond 90 minutes.
When fly sparging, I always mash out by adding some near boiling water to raise the mash temperature up to 165 - 168F. If I don't do this, the sparge temperature stays in the 150's - low 160's and reduces my efficiency by about 10%
I then sparge for 45 - 90 minutes with acidified sparge water to keep the pH down, and carefully monitor the gravity of the runnings with a refractometer towards the end of the sparge.
Occasionally I will get down to 2.25 brix (1.008 gravity) before I have collected the required volume, in which case I stop the sparge, and make up the volume with water.
Usually, I reach the required volume before the gravity has dropped to the cut-off point. If you sparge below this point (and some say that the cut-off point is 1.010 gravity), you will start to extract excess tannins because the pH of the runnings will be above 5.6.
I hope this hasn't confused you. It's really quite simple once you have done one or two batches

-a.

I understand that if my sparge water is too high, I will extract tanins and other things that I don't want. I also understand that it is ideal to get the mash to 168F to stop the enzyme action. My question is why do you NEED to stop the enzyme action?

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I hope someone can answer this because my limited understanding was that you DON'T stop enzyme action until you get to some higher temp (176 degrees F is the number popping into my head) and you don't WANT to stop enzyme action during the lauter/sparge (it will happen soon enough during the boil). But I could be totally wrong on this...which is why I wanted to bring this particular point back up.

In other words...I thought it was all about extracting the sugars.

enzyme action stops at 170 (mash out) witch is not really nessary unless you are trying to duplicate batches. really we are splitting hairs. The trick is not to sparge with water over 170, that's the point where you extract tannins. Batch sparging this is more critical but fly sparging its not because if done right the hotter water never leaves the mash tun.

hammer one said:

enzyme action stops at 170 (mash out) witch is not really nessary unless you are trying to duplicate batches. really we are splitting hairs. The trick is not to sparge with water over 170, that's the point where you extract tannins. Batch sparging this is more critical but fly sparging its not because if done right the hotter water never leaves the mash tun.

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I dont understand this... why would the hot sparge water not leave the MLT?

I mash for 60 mins almost always, turn up the HERMS to 173F for mashout for 20min. I then swap one hose and start the fly sparge with the 173F water from the HERMS HEX. My grain bed remains in the high 160s during the entire process.

I completely drain my HLT and MLT during the sparge so there are definately no sugars left in suspension in excess water.

I am a beginner that fly sparges in a water cooler. The first time I used 170 degree water and ended up with a 160 degree sparge. I almost met target gravity. The second time I used 180 degree water and had about 165 degree sparge. I exceeded target gravity by a bit. Is it risky to use this hotter sparge water? If I go to adding near boiling water to raise the temp, how much water should I add to get a 5 gallon batch near 170?

jgroeger said:

I am a beginner that fly sparges in a water cooler. The first time I used 170 degree water and ended up with a 160 degree sparge. I almost met target gravity. The second time I used 180 degree water and had about 165 degree sparge. I exceeded target gravity by a bit. Is it risky to use this hotter sparge water? If I go to adding near boiling water to raise the temp, how much water should I add to get a 5 gallon batch near 170?

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In decoction brewing a portion of the mash is removed and boiled. This does not extract tannins because the pH is too low. As long as your pH is where it should be (under 6.0) the temperature isn't critical.

Since you are fly sparging (I have to wonder why, but that's a different question) you need to bring the grain bed and all the wort in the mash tun to over 170 and keep it there for at least 10 minutes to stop the enzymes from continuing to break down the sugars into more fermentable pieces. Then you begin your sparging which should be done slowly to avoid channeling in the grain bed. I've heard mention of 45 minutes to over an hour to do a proper fly sparge.

You could make this much simpler by batch sparging. With batch sparging you drain the first runnings, add hot water, stir, and drain again. No worries about mashout, it isn't needed because you don't let the grains sit in the sparge water for very long. No worries about sparging too long so that the pH rises enough to extract tannins, just drain, sparge, and done.