What happens if I mash all at once?

[Patirck]

I was wondering why I need to do the mash in two steps - once for an hour or so and then again with less water for 15 minutes or so?

Can I doe this in one step if my mlt is big enough? (it is).

For instance:

I have a recipe with 8.25 lbs of grain. Using an absorbtion factor of .1 gallons per pound the grain will absorb .825 gallons of water. I want a pre boil volume of 6.25 gallons. Why not just put (6.25 + .825) 7.075 gallons of water at the appropriate strike temperature and let it stew for an hour, then vorlauf and put it in the bk all at once?

Given my equipment, this would make the process much easier.

 

[prosper]

it'll work. It's similar in concept to 'Brew in a Bag.'

The only real downside is that you're not going to extract as much of the potential sugars from your grains as you would if you'd sparged (rinsed) them, so you'll get a lower efficiency. But, given the cost of base malt, it should only amount to a dollar or so worth of extra malt to account for the lower efficiency.

The efficiency will get proportionally worse as you brew bigger (higher gravity) beers, too, so keep it to around 1.060 with this technique.

 

[FDillon00]

You can-ish.
First you have understand the process. The way you descibe it the "Second Mash" for the last 15 minutes or so isn't really a mash. It's more of a rinse to get the last bits of fermentables off the grain husks, this is called "Spargeing" or "The Sparge".

Now what you are want to do is a "NO-Sparge" brew. Which I have only just started reading about. Someone shortly will supply a link to it.

 

[FDillon00]

EDIT: Double POST, server lag.

Here's the link.

This seems in no way "Brew in a Bag", he is asking about mashing steps not the idea of putting grains in a fine mesh bag to reduce turb in the final product.

So my suggestion is read some more about traditional mashing techniques, and look at the link above for "No Sparge" help.

 

[prosper]

brew in a bag has nothing to do with reducing trub, it's all about minimizing the amount of equipment you need, by mashing in your full volume of water.

 

[Starderup]

If you taste a couple of grains after your initial lauter, you will know why sparging is useful. The grain still has a lot of sugar in it. Sparging gets that into your boil kettle.

 

[Patirck]

If you taste a couple of grains after your initial lauter, you will know why sparging is useful. The grain still has a lot of sugar in it. Sparging gets that into your boil kettle.

Wouldn't this get done if I vorlauf? I guess it seems to me that rinsing with plain water versus rinsing with wort wouldn't make a big (if any) difference.

 

[Starderup]

Vorlauf is to set the grain bed. That wort is saturated with sugars, and won't really pull any more from the grain. Hot water will.
If you do the same recipe both ways, and measure your O.G., I think you will see the benefit of sparging.

 

[Patirck]

What percentage of grain would I have to add to make up for the sugars not gotten in the sparge? If this is a matter of an extra pound of 2 row for a 8 or 9 pound grist I think that may be worth it. Also - what if I add a bit extra water and extend the boil so I boil off some of the water and end up with a higher sugar:water ratio?

I'm trying to see if there is some math out there that will allow me to end up with say 1.050 after boil with 5.5 gallons. If it is a matter of an extra $2 worth of grains, I'd say that is worth it. On the other hand, if it will be unpredictable, that may not be worth it.

 

[samc]

If you are going to do it that way you should really get yourself some fabric (voile) and make a BIAB bag. Then you can skip the vorlauf and just pull and drain the bag. Many BIAB'ers report similar efficiencies so the need for extra grain would be zero.

 

[novafire]

One of the main reasons that people mash with a set amount of water and then sparge is that it is recommended to mash with only about 1.25 qt water per pound of grain. If you mash with too much water, the enzymes are too diluted to get a good conversion from starch to sugar.

So with 1.25 qt/pound you would have a little over 3 gal of water used in a 10lb mash.

You can stretch that beyond 1.25 qt/pound to make a thinner mash, but only so far. You could search the forum for "thin mash" and probably find some good info.

Also, as mentioned before, if you skip the sparge, there will always be more sugar left in the grain. Look at it this way: you can rinse more dish soap out of a glass by rinsing it twice with a cup of water than by rinsing it once with 2 cups water.

 

[Starderup]

Water is cheaper than grain, so the sparging is a no brainer for me. Otherwise, the BIAB is a good option unless you are doing 10 gallon batches.

 

[Bobby_M]

You can mash with a ratio up near 4qts per pound if your water chemistry is conducive to a good mash pH. Of course this is a complex topic that can't be over generalized. It's a better idea to stick with 2qts/lb max and make up the remaining volume in sparge.

Assuming 100% conversion of starch to sugar, you can easily calculate your efficiency lost to no sparge. 10lbs of grain, capable of 36PPG is 360 points. In 7.5 gallons of water you have 360/7.5 = 1.048 gravity in the mash. If you run that off, you'll have 6.5g @ 1.048. You'll have one gallon of 1.048 locked in the grain for a max theoretical efficiency of 86.7%. This is assumes 100% conversion and no additional wort lost to dead space. In practice, the crush is going to be too coarse for 100% conversion/extraction.