First AG questions

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PalmBeachPaul

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Hi Guys, I’m planning to brew my first AG this weekend and a have some questions.
I never understood the OG issue; the recipe calls for OG: 1.051, should I take the reading before boil or after?
To calculate my efficiency, which OG reading should I use? Pre boil or post boil?
Let say I missed my OG, just for example I hit an OG: 1.045. How much DME should I use to compensate on a 5.5g batch? 1 cup = 2 points? Something like that?
I’m worried about propane. I’m using a Bayou classic. Half a tank is enough for a 5.5g brew day?

Thanks a lot for your help and advice. I love this forum.

Cheers :mug:
 
OG = Origional Gravity
You measure OG at the end of the boil. The liquid volume matters because the smaller it gets the higher the sugar content.

If you do not get the OG you desire just try to do better next brew day. Unless you are really not paying attention you should be very close anyway. The beer will be good. I do not believe in adding DME to make up lost gravity points. I believe that should give you incentive to correct the problems that are causing it. Otherwise why bother to improve your process.
 
Hi Guys, I’m planning to brew my first AG this weekend and a have some questions.
I never understood the OG issue; the recipe calls for OG: 1.051, should I take the reading before boil or after?
To calculate my efficiency, which OG reading should I use? Pre boil or post boil?
Let say I missed my OG, just for example I hit an OG: 1.045. How much DME should I use to compensate on a 5.5g batch? 1 cup = 2 points? Something like that?
I’m worried about propane. I’m using a Bayou classic. Half a tank is enough for a 5.5g brew day?

Thanks a lot for your help and advice. I love this forum.

Cheers :mug:

Hi there. The original gravity is always taken post boil. A lot of people will check their gravity pre-boil and use that to adjust their hops schedule to fit the gravity at that point. But the OG will be the gravity of the wort going into the fermenter.

I never add DME to get to gravity. I just sort of go with whatever I end up with, but at this point I know my system and I get the same efficiency pretty much every time. So I take that into account when I am making my recipes and I adjust there.

Do you have a program for recipes? Beersmith will tell you what your pre-brew gravity should be if you want to know it. Regardless of which one you might have, they're all useful in showing you the numbers. They will also tell you how much DME to add if you want to.

And 1/2 a tank will be more than enough. I get through 4-5 beers on a tank.
 
You take your gravity before you boil. 1.051 is the gravity before you boil, however you should have a gallon or so more than you are making so that when your boil is complete you have 5 gallons of 1.051, so your preboil graviy at 6 gallons should be 1.040 or so. You should have enough propane, but with an all grain, you have to heat your strike water rather than just brewing an extract, and depending on if you are batch sparging or fly, but you should have enough Propane. How many pounds of base grain are you using?
10pounds of grain
10(35)=350(.75)=262.5/5.5=47.72 or 1.047
The 75 is assuming you get 75%. Then the 5.5 is your finished gallons.
35 is the max potential gravity of most basemalts per pound at 100% efficiency
 
You take your gravity before you boil. 1.051 is the gravity before you boil, however you should have a gallon or so more than you are making so that when your boil is complete you have 5 gallons of 1.051, so your preboil graviy at 6 gallons should be 1.040 or so. You should have enough propane, but with an all grain, you have to heat your strike water rather than just brewing an extract, and depending on if you are batch sparging or fly, but you should have enough Propane. How many pounds of base grain are you using?
10pounds of grain
10(35)=350(.75)=262.5/5.5=47.72 or 1.047
The 75 is assuming you get 75%. Then the 5.5 is your finished gallons.
35 is the max potential gravity of most basemalts per pound at 100% efficiency

Original gravity is a post boil measurement.
 
OG = Origional Gravity
You measure OG at the end of the boil.
--cut--
I believe that should give you incentive to correct the problems that are causing it. Otherwise why bother to improve your process.

First to the OP - Yes, overall efficiency and recipes call for the post boil, adding yeast to make beer measurement, after all that is where your job ends and the yeast take over. After that your just the manager trying to make them happy to do the voodoo that they do, soooo well.

WBC Hit it on the head, I have had three AG batch's and even though my efficiency is horrible, I end up with fantastic AG light beer, and I'm working my a$. off to get where I think I should be.
The purpose of detailed measurements is to determine where you are, and to help you get where you want to be.
 
I'm just going to respond about the Propane situation because I actually figured it out this past brew.

I too use a bayou classic and was worried about propane usage. So I filled the tank, took an initial weight, got around 33.4lbs, took a weight after hour long full boil & got 32lbs. So for a 60min full boil, I only used 1.4lbs of Propane. The tank has a tare weight of 18.8lbs stamped on the handle, so that's almost 10 brew's for my setup.
 
Do you have a program for recipes? Beersmith will tell you what your pre-brew gravity should be if you want to know it. Regardless of which one you might have, they're all useful in showing you the numbers. They will also tell you how much DME to add if you want to.

And 1/2 a tank will be more than enough. I get through 4-5 beers on a tank.

I downloaded Beersmith trial version, but I can’t find the pre boil gravity calculation, same with the DME. I’ll keep playing with it, looks very useful. I guess my ½ tank of propane should be fine.

“The 75 is assuming you get 75%. Then the 5.5 is your finished gallons.
35 is the max potential gravity of most basemalts per pound at 100% efficiency”

In John Palmer’s book it says that some grains have different potential gravity, should I take 35 as a general rule or is it better to calculate efficiency using every grain potential??
I’m just worried about efficiency because if I hit a really low OG I don’t know how the beer is going to turn out.

Thank you so much to everyone for taken the time to answer this post, it really help me a lot. Thanks. :)
 
Bulk Priming with Other Forms of Fermentables
Sugar Type 5-gallon Batch of Beer
CORN SUGAR (dextrose) 3/4 Cup
brown sugar 2/3 Cup
cane or beet sugar 2/3 Cup
dried malt extract 1 1/4 Cup
honey 1 Cup
maple syrup 1 1/4 Cup
molasses 1 Cup



I do not like DME for fermentation - Local Honey is my choice!

BeerGrills
 
I downloaded Beersmith trial version, but I can’t find the pre boil gravity calculation, same with the DME. I’ll keep playing with it, looks very useful. I guess my ½ tank of propane should be fine.

“The 75 is assuming you get 75%. Then the 5.5 is your finished gallons.
35 is the max potential gravity of most basemalts per pound at 100% efficiency”

In John Palmer’s book it says that some grains have different potential gravity, should I take 35 as a general rule or is it better to calculate efficiency using every grain potential??
I’m just worried about efficiency because if I hit a really low OG I don’t know how the beer is going to turn out.

Thank you so much to everyone for taken the time to answer this post, it really help me a lot. Thanks. :)

Well, if you already have the trial of beersmith on your computer, put in the grain you are using and then play with the efficiency field.

As for the pre-boil... It is on the pbrew sheet. If you click the "preview brew sheet" button it will come up there.
 
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