First Partial Mash. Don't understand instructions.

[HokieHomeBrewer]

First off, I've looked at the great Partial Mash Walkthrough tread on HBT.

Here are the vague instructions for my 5 gallon partial mash recipe.

Place crushed grains in a steeping bag. Steep the grains at 155 F in 3.0 qts of water. OK I understand so far but for how long?30-45 mins?

Remove bag and place it in colander over the brewpot. Rinse the grains with approximately 2 qts of 170 F water Understood , bringing volume to at least 3 gallons. I don't understand this. 5 quarts equals 1.25 gallon. Do I then pour in another 1.75 gallons of water and then reheat to a boil???

Add extract hops etc...I understand the rest. But I don't understand the first part.

The recipe calls for 1 lb of 2 row and 8 oz of crystal. I'm assuming I heat up 3 quarts of water to 155 (or higher), then line the pot with a big strainer bag and add the grains....but how long do I leave them in there? On my other burner I'll be heating up 2 qts of water to 170 and then I'll be pouring that over the grains into the 3 qts below correct?

So then what? Top up to 3 gallons and then extract, hops, etc?

Please help.

 

[Demus]

Your question requires a book to answer. Fortunately John Palmer's "How to Brew" is free on line. Not trying to condescend, but you're asking about the entire mashing process which is a bit more involved than a quick forum post. I've been brewing all grain for a few years now and continue to learn. I recommend reading at least 2 books on the subject before attempting a mash, even if it is partial...

 

[KepowOb]

I agree that more reading will definitely help you out... and also understand that I haven't done a partial mash, so please take what I say with a grain of salt (the only reason I am commenting is I've done a ton of reading and at least understand the basics of it, in theory...). Someone else will likely chime in with better advice soon (or already has, as I write this).

I do find a few things in the instructions a bit strange though. If you are to heat your water up to 155F, when you put your grain in, it's going to drop in temp. Mashing is usually done at 148-152, and I believe that you normally get your water up to about 160+, since it's going to drop down when you add your grain. There are calculators to help you figure this out though, including one built into BeerSmith if you have it. You'll want to be pretty precise (and keep a very close eye on the temp while you mash) with this though, as small differences can have a big effect on the conversion.

You're right when you say you won't have 3 gallons, and I'm pretty sure you'll just need to top off from there to get to 3 (or more?). Is it a 5-gallon kit and you'll be doing a partial boil?

 

[HokieHomeBrewer]

I agree that more reading will definitely help you out... and also understand that I haven't done a partial mash, so please take what I say with a grain of salt (the only reason I am commenting is I've done a ton of reading and at least understand the basics of it, in theory...). Someone else will likely chime in with better advice soon (or already has, as I write this).

I do find a few things in the instructions a bit strange though. If you are to heat your water up to 155F, when you put your grain in, it's going to drop in temp. Mashing is usually done at 148-152, and I believe that you normally get your water up to about 160+, since it's going to drop down when you add your grain. There are calculators to help you figure this out though, including one built into BeerSmith if you have it. You'll want to be pretty precise (and keep a very close eye on the temp while you mash) with this though, as small differences can have a big effect on the conversion.

You're right when you say you won't have 3 gallons, and I'm pretty sure you'll just need to top off from there to get to 3 (or more?). Is it a 5-gallon kit and you'll be doing a partial boil?

Correct it's a 5 gallon batch and I'll be doing a partial boil....I'm guessing I'll just top off with 1.75 and bring to a boil. You're also correct about the grains cooling down down the temp of the water so I'm going to probably heat it up to 160 and add the grains which will drop it to 150-153ish I'm thinking...then I'll just heat it up a degree or two.

I'm surprised they don't mention how long to let the mash sit for but from what I've read it seems 30-45 mins is the norm.

 

[signpost]

Heat the water to about 160F. Then add the grains. If that drops the temp to anywhere around 152-155F you are fine. No worries. Let it sit there for 45 or so, and the enzymes should have finished their work of converting the starches to sugars (people normally mash for an hour when doing all-grain, but for such a small amount of grain 45 min. should be plenty).

That is when you pour the 170F water over the grains to rinse out as much of the sugar as possible.

Then you top it up to whatever you want your boil volume to be, bring it to a boil, add extract and follow your hop schedule per the recipe.

Many kits have really terrible instructions. When the instructions are stupid, do what you think makes sense.

 

[HokieHomeBrewer]

Heat the water to about 160F. Then add the grains. If that drops the temp to anywhere around 152-155F you are fine. No worries. Let it sit there for 45 or so, and the enzymes should have finished their work of converting the starches to sugars (people normally mash for an hour when doing all-grain, but for such a small amount of grain 45 min. should be plenty).

That is when you pour the 170F water over the grains to rinse out as much of the sugar as possible.

Then you top it up to whatever you want your boil volume to be, bring it to a boil, add extract and follow your hop schedule per the recipe.

Many kits have really terrible instructions. When the instructions are stupid, do what you think makes sense.

Thanks so much! This is pretty much what I assumed I should do but I was just taking a somewhat educated guess. Thanks for confirming!

 

[Demus]

Grain converts the starches to sugar based on many factors, amount of grain is not one of them. If a mash takes an hour, a mash takes an hour. The enzymes in the grain have no idea you are doing a "partial mash" and work at the same rate they do on an "all grain" recipe. The main control point is temperature, followed by water/grain ratio and water chemistry. Also the types of grains being mashed have different properties that affect the rate and efficiency of conversion. This is why I advise reading. You are as likely to get bad information on this site as you are to get good, so you need a foundation to sort through it. All brewing is trial and error to some degree, but knowledge and information help minimize the error part...

 

[signpost]

Thanks for correcting me, Demus.

And yes, there is no substitute for reading credible sources about this kind of stuff. But at the same time, don't be afraid to try something just because you haven't read every text on the subject.

 

[HokieHomeBrewer]

Grain converts the starches to sugar based on many factors, amount of grain is not one of them. If a mash takes an hour, a mash takes an hour. The enzymes in the grain have no idea you are doing a "partial mash" and work at the same rate they do on an "all grain" recipe. The main control point is temperature, followed by water/grain ratio and water chemistry. Also the types of grains being mashed have different properties that affect the rate and efficiency of conversion. This is why I advise reading. You are as likely to get bad information on this site as you are to get good, so you need a foundation to sort through it. All brewing is trial and error to some degree, but knowledge and information help minimize the error part...

So with a recipe that calls for 1 pound of 2-row and 8 ounces of Crystal 40 in 3 qts of water at 155 f....how do I determine the mash time? I read Palmers last night and I came across lots of information regarding what's happening while it's mashing and why we do it, but I still have no clue how long I'm supposed to do it for. Like, how do I know when I'm done? I read you can taste it....or use iodine...but is there a number I'm looking for or a formula I can use?

With the fermenter you've got an air lock and a hydrometer and an FG you're looking for to know your finished. What is my target here?

If I let it sit for 60 minutes as opposed to 45 will that extra 15 minutes harm my beer? Or at worst am I just wasting 15 minutes? I always err on the side of caution so if wasting 15 minutes is worst case scenario then I'm fine with that.

Thanks.

 

[Demus]

So with a recipe that calls for 1 pound of 2-row and 8 ounces of Crystal 40 in 3 qts of water at 155 f....how do I determine the mash time? I read Palmers last night and I came across lots of information regarding what's happening while it's mashing and why we do it, but I still have no clue how long I'm supposed to do it for. Like, how do I know when I'm done? I read you can taste it....or use iodine...but is there a number I'm looking for or a formula I can use?

With the fermenter you've got an air lock and a hydrometer and an FG you're looking for to know your finished. What is my target here?

If I let it sit for 60 minutes as opposed to 45 will that extra 15 minutes harm my beer? Or at worst am I just wasting 15 minutes? I always err on the side of caution so if wasting 15 minutes is worst case scenario then I'm fine with that.

Thanks.

First, 3 quarts would be a little thin for 1.5 pounds of grain. Most use a ratio of 1.25-1.5 quarts per pound of grain.
You can't really predetermine mash time. Like I said before, it has many influences. Personally I just mash for an hour, put a drop on a white plate and add a drop of iodine. If it turns purple, starches are present which are not fermentable so the properties of your beer will be affected. Wait another 29 minutes and repeat. You could do this iodine test sooner if you wanted to save time, but there are intermediate stages of the process that the iodine test wouldn't reveal. In other words, it's not like one minute you have starch, the next you have perfectly fermentable sugars. It's a process. There's no real downside to waiting an hour if it was done in 45 minutes. But rush it and you'll get starches, unfermentable sugars and poor extraction....

 

[HokieHomeBrewer]

First, 3 quarts would be a little thin for 1.5 pounds of grain. Most use a ratio of 1.25-1.5 quarts per pound of grain.
You can't really predetermine mash time. Like I said before, it has many influences. Personally I just mash for an hour, put a drop on a white plate and add a drop of iodine. If it turns purple, starches are present which are not fermentable so the properties of your beer will be affected. Wait another 29 minutes and repeat. You could do this iodine test sooner if you wanted to save time, but there are intermediate stages of the process that the iodine test wouldn't reveal. In other words, it's not like one minute you have starch, the next you have perfectly fermentable sugars. It's a process. There's no real downside to waiting an hour if it was done in 45 minutes. But rush it and you'll get starches, unfermentable sugars and poor extraction....

Perfect, this is exactly what I was looking for. I'll do that then. So you're suggesting drop the 3 qts. down to around 1.9-2.25? Will do.