Rookie All Grainer - High Gravity Reading?

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donerj03

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Ok, so I have done 3 all grain batches now and I'm trying to hone in my skills...I'm currently using a 52qt Igloo cooler mash tun trying to achieve at least 6 gallons of wort to boil down to a total of 5 gallon batches. My problem is hitting my hydrometer readings. I suck at that! I'm new to taking hydro readings because it wasn't a priority when I was doing extract brews...so I'm not really sure when I should be taking the reading and what the readings actually mean.

I brewed last weekend a Red Rye PA from Midwest. I really love Rye beers so I wanted to make sure I hit my numbers on this batch. So I took readings from my sparge runnings when the wort is about 168 degrees and the hydro reading is very low (1.0000, I think thats the same as water...). However, when I collect all the wort in my pot to start boiling the reading is different (1.033 @ 155 degrees). So my initial though is that since the beer needs to be at 1.042 and I'm currently at 1.033 I need to boil down some of the water to get a higher gravity reading (not sure if that is correct philosophy). After I finish my 60 minute boil my wort dropped from 6 gallons to 5 and I took another hydro reading. The reading at 80 degrees was 1.060! Either I really suck at taking hydro readings or I boiled the crap out of my beer...

Can somebody give me the base ground work of what the hydrometer tells you and when during the all grain process should I be taking readings? Typically do you have a lower reading pre-boil and then you try to increase the gravity through evaporation of water post-boil? I know temp of the wort makes a difference in the hydro readings so do I have to cool the wort before I take a reading (that sounds like a pain in the @ss and would slow my process). What is the easiest way to make sure my beer hits its gravity readings? Please let me know your thoughts.

Thanks!
-newbie
 
Yes your reading will go up after the boil due to evaporation. There are free brewing calculators you can search for online to correct your hydro reading for temp.
 
Your hydro reading should be 10-20% lower than target OG at begining of boil. It must be cooled because of thermal expansion. The correction is huge and inaccurate for boiling wort.

My newest methos is to start with 6.5-7.0 gallons and I will end with 5-5.5 gallons. Easiest is to get a refractometer to measure gravity. It does not need to be corrected for temperature if it has an ATC (About $35 on ebay). This is not as accurate as a hydrometer, but will be close for OG. I use it so see if I need to add a little more wort or water to keep the OG from being way to high. Caution, the refractometer will measure FG very poorly. It must be corrected as the alcohol produced messes it up. Most beer software will correct it, but I use a hydrometer for FG. Refractometers are used for measuring sugar in fruit, so alcohol messes up the reading.
 
Hydrometer readings (half for repeatability)

I take one at the end of the sparge runnings.
One pre-boil, (after it is mixed in by all running out into the pot)
One Post Boil (Post Aeration, so it is mixed in well)
One post-primary
One post-secondary

Works well for my records. HOWEVER, you NEED TO MAKE SURE you correct the hydrometer reading for temperature. Hydrometers are calibrated to be accurate within a specific temperature range. Yours will be quite accurate around 60-75 most likely. YOU must adjust these readings in order to get a true SG.

There is a calculator for adjusting this within most brewing programs and you can find web tools at the following links:

Here
Here
Here is a table


The easiest way to make sure your beer hits SG as you want it to, is to figure out your efficiency and have it calculated right in the beginning so that you aren't using too much, or too little grain. Also to refine your process and find stability, and adjust your process from there.
 
This is awesome information! Thank you dbhokie and brauerei for the info!

So I have one more question for you. what does it mean if I miss the hydro readings according to taste? If I'm low on the hydro reading does it correlate with a specific taste to my beer? If I'm high on the hydro reading what will it mean to the taste?

I guess hydro readings are indicators of sugar in the wort, correct? So if I'm high on the hydro reading then it will have more of a sugary, sweet taste with more alcohol? If I'm low on the hydro reading then it will not be as high alcohol content and will taste not as sweet?

I'm hoping to use this information to figure out what my beer actually should taste like. All my beers are drinkable, but I never know if they taste the way they should (if that makes sense...).
 
Final gravity would be one indicator of how sweet the beer would be. A drier beer will have a lower FG than a sweeter beer. However it alone won't tell you much about the alcohol in the beer. The % alcohol is calculated using SG and FG and illustrates how much sugar the yeast has converted to alcohol.
 
Rogue got ya there. There are a variety of factors that affect how fermentable the wort is. On top of that you have what is called the attenuation of the yeast. Which is basically how effective the yeast is at converting the sugars in the wort to alcohol. Some adjuncts and malts you add are less fermentable. They put more non-fermentable sugars and forms of carbohydrates into your wort. This will raise your FG and make your beer "sweeter". Some yeast do not have very high attenuation, this can contribute to the same basic precept. When your beer finishes very low, say 1.004-6, it would be a very "dry" beer. When it finishes quite high, it will be "sweeter" and fuller bodied. These are terms I have come to recognize while tasting beers and considering ingredients. To an undistinguished palate (mine still is quite so), a very malty beer, that is in fact very dry and very light bodied the maltiness may convey an idea of "sweetness". Some Belgians are good examples. When you use hops towards the end of the boil, you will get more aroma and flavor from these, you will find a lot of your flavors contingent on this. In the case of many belgians, a highly attenuated yeast produces more esters and the yeast accounts for a lot of the flavor. Everything from your malts, to your temperature of the mash, to hops, adjuncts, yeast, and fermentation affects a beers flavors. That is why it is good to write down as detailed as possible notes when brewing if you want to start discerning the differences even more. You will know the flavors that may rise when fermentation temperatures are too high, which then will let you expect them out of another similar batch with similar yeast, or will prepare you to have colder ambient temperature, or warmer..etc.

Your OG reading just measures the amount of the sugars in your wort. It has little to do with your ending ABV, it is more your potential ABV. For instance a beer with a OG of 1.056 and a FG of 1.01 would be about 6.1%. A beer with an OG of 1.068 and fG of 1.023 would be about 6 % alcohol, the same beer if it had finished at 1.01 would hav been more around 7.7. There are ABV calculators everywhere on the net, or you can use equations and figure it out yourself if you would like. Just remember to correct your gravity readings for temperature, and take them at the point when the wort is best mixed. See the thread about SG readings being off.

A basic idea is: Sugars at the beginning(OG)-sugars yeast took out = Sugars at end(FG)
The sugars the yeast took out roughly ends up being your alcohol by weight, then you convert it to volume...ABV=[(OG - FG)(1.05)]/0.79
 
wow, I think I have learned more in these responses than I have in the past 10 years brewing...THANK YOU!

Ok, so back to the beer that I brewed this weekend. If my OG reading was higher then expected (1.060 vs 1.042) can I add water at the end of the boil to lower the reading to desired level? Is that even a good idea to do? Also, how do I prevent this from happening in the future? If I hit a higher OG then the recipe states does that mean that my mash was very efficient??

Sorry for all the questions. I find this very interested and there are a lot of moving parts to understand...
 
If your OG was higher than expected and you want a specific final gravity, first it would be good to figure out why. You ended up with 6 gallons of wort at 1.033 @ 155 degrees. This is actually more like 1.053, 6 gall @ 60 degrees. So your corrected preboil is 1.053

Assuming that your OG reading is correct (the wort was well mixed when you took it, and you didn't got an unbiased sample) then we know that the recipe assumed a mash efficiency lower than what you actually got. This can be due to a more efficient setup and sparge than expected, different steep temperature than in directions, and other variables.

You could add tap water in order to hit your desired OG, however, I would say don't worry about it. (Plus you'd have a volume of about 7 gallons, it would throw off your IBU's and flavors as well as lessen the alcohol. You will have a fine beer, just put it in. It will be perhaps a bit stronger than you planned on, depending on the yeast strain and it's attenuation. If the yeast doesn't have a very high attenuation it may be a bit stronger and bit fuller bodied.
 
If I am reading this correctly your initial pre-boil reading of 1.033 @ 155, when adjusted for temperature would actually be 1.053. Your 60 min boil then further concentrated the wort upping it to 1.062, after adjusting for a reading at 80 degrees. If this is a red ale you would be just a couple points high of the style.

It would be worthwhile to post your recipe and a bit about your process. There are folks on here that can probably provide better insight into what may have happened with that information.
 
I thought hydrometer readings at 90°+ were inaccurate regardless of calculators?
 
When you pull a preboil sample, make sure you've stirred the wort well before hand. It's common for the lighter gravity later runnings to sort of float on top or at least stratify a bit. I don't trust your preboil gravity reading one bit.
 
wow, I think I have learned more in these responses than I have in the past 10 years brewing...THANK YOU!

Ok, so back to the beer that I brewed this weekend. If my OG reading was higher then expected (1.060 vs 1.042) can I add water at the end of the boil to lower the reading to desired level? Is that even a good idea to do? Also, how do I prevent this from happening in the future? If I hit a higher OG then the recipe states does that mean that my mash was very efficient??

Sorry for all the questions. I find this very interested and there are a lot of moving parts to understand...

It sounds like you are getting pretty good efficiency, What efficiency was the recipe planned for? Have you been consistently high on your OG for these first 3 batches?
 
My process is to collect my full boil volume and stir well. I will then pull a hydro sample and put it in the freezer for about 20 minutes and this chills it to just about 60F and then take a reading. This is done while the boil is underway.

Depending upon the results I can then either add some DME to raise the gravity or decide to boil longer. I usually do 90 minute boils so if I'm higher than expected I can also just do a 60 minute boil.

It's taken me several batches to dial in the system but after that I've got my process pretty spot on.
 
Brauerei said:
Caution, the refractometer will measure FG very poorly. It must be corrected as the alcohol produced messes it up. Most beer software will correct it, but I use a hydrometer for FG.

A caution here for all of the refractometer users out there. Sean Terrill (http://www.seanterill.com) has done a great deal of research on using refractometers to calculate gravity after fermentation had started and alcohol is present. He was featured on Basic Brewing Radio with James Spencer. Good episode. Anyway he found that NONE of the current calculators of software that supposedly correct for the presence of alcohol actually corrects for the presence of alcohol. He has a calculator on his website that does a pretty good job. But even still he recommends using a hydrometer in instances where you need guaranteed accuracy.
 
Thank you for all the responses! I have done a total of 3 all grain batches so far. My first two I was well below the desired OG reading so that is why I'm shocked that I was high on this one. Also, I didn't even think to stir the wort before taking my sampling so that may be the issue with my weird hydro readings....I'm a newbee...

So the recipe for this is the following from Midwest:
Red Rye P.A.
9lbs Maris Otter
2oz Chocolate Rye
3oz Cara Rye
3oz Crystal 50-60
20oz Rye Malt (I screwed this one up in the grain room and only added .2lbs)
4oz Flaked Rye (pre-mixed)
2oz Columbus,
1.5oz Centennial (can't buy .5oz of hops so I threw in 2oz...I like hops :)
Yeast: Fermentis US-05 dry
 
My process is to collect my full boil volume and stir well. I will then pull a hydro sample and put it in the freezer for about 20 minutes and this chills it to just about 60F and then take a reading. This is done while the boil is underway.

Depending upon the results I can then either add some DME to raise the gravity or decide to boil longer. I usually do 90 minute boils so if I'm higher than expected I can also just do a 60 minute boil.

It's taken me several batches to dial in the system but after that I've got my process pretty spot on.

This is very helpful! I'm always looking for ways to optimize my brew day so that I'm not running around with my head cut off. :rockin:
 
This is a worksheet I had made myself to help me out keeping track of each brew day.

See if it will help you, it also does many helpful calculations such as attenuation, Points per gallon, points per pound, IBU..etc

Example (Filled out)
This one is Blank

Hopefully that helps you in the future a little for free.

EDIT: I accidentally deleted the wrong things in the first link post. I corrected the document and locked the correct cells. Please try again if you haven't already.
 
This is a great spreadsheet! I wish I could see the formulas to figure out what you are actually measuring. For instance how do you measure yeast attenuation? How do you calculate final gravity? What are grain points and how are they calculated?

Very cool stuff!
 
Yeast Attenuation is:

(Original Gravity-Final Gravity)/(OG-1)

This gives you the percentage of effectiveness that the yeast apparently converted at. So if you take your Desired OG, and your Desired FG, it will tell you the attenuation you expect the yeast to act at. Then compare that to the attenuation the lab gives you with it, and you will know if it is realistic. If you are washing and storing your own yeast, you should make sure to mark them with attenuations.

Your final gravity is measured with a hydrometer, You measure it before you bottle, and before you add priming sugar(although no big deal if after, the priming sugar throws it off minimally, and you can figure that out as well). You must make sure the wort is well mixed, without aerating.

Grain Points are simple.

You can find the grain points either from your LHBS, or online very easy from the manufacturer or a variety of different places. I actually have been improving my spreadsheet so I will give you an update, kind of finicky when you move things around. However you have what is called "Potential Points".

Let's take Belgian 2 row Pilsner. It has Potential of 1.036. That means with this grain you can add 36 grain points per pound at the very maximum.

(1.036-1)*1000=36
36*#s of grain/Batch Volume = Potential Points Per Gallon your grain can add to your brew. If you sum all of this up from all of your grains and saccharide additions, you will have your Total Potential Points Per Gallon. Now The points per gallon you actually get can be measured from your preboil SG. Actual Points/Potential Points = Actual Mash Efficiency.

You get your actual points by:

((PreboilSG-1)*1000)*PreBoilVolume/GristBill(total pounds of all grains)

The sheet I have corrects for saccharide Additions that you make post-mash, or in the boil. It would use these numbers as well.

Your finished PPG would be ((FG-1)*1000)*BatchVolume/Gristbill
 
Here is one that shows more of the calculations and updated a lot, some bugs fixed too..I am working on expanding it to include all water chemistry and fermentation aspects as well.

Click here for workbook in Excel format.

This is a Single Temperature Infusion All grain sheet, it would work fine for extract boils as well, but it does not take into account step mashing or decoction mashing. I am working on separate sheets to calculate the variables with those techniques. (It would still calculate your PPG, PP, and many other things, but not all variables would be accounted for).

EDIT: Notice also that it will calculate post-mash saccharide additions. (EG: Honey LME,DME), You must specify steep times and boil times for it to pick up on the fact that the item will not be added in the mash. It will then give you the point addition of the item, (how much gravity it will add to your Pre-Boil SG), and after you enter in your temperature, it will convert the PreBoil SG accounting for Extract and saccharide additions, and temperature, and give you a corresponding corrected PreBoil SG, that will make the numbers more accurate for your Mash efficiency, Points and such thing. Technically For a more accurate prediction I need to move the equations, and if it is a saccharide addition, the prediction shouldn't lump it in with Mash Efficiency. I will correct that later, it is closer than many programs currently.
 
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