Original Gravity testing

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jdphillips73

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exactly at what point do i test for OG? preboil, postboil, wort still hot, cooled? I have no idea.
 
Measure OG right before pitching yeast into cooled wort.

Your hydrometer has a calibration temperature. It's best to measure at that temperature, otherwise you'll need to adjust the reading.

The specific gravity changes during the boil because water is boiled away, and s.g. changes at different temperatures because warm liquid is less dense.
 
exactly at what point do i test for OG? preboil, postboil, wort still hot, cooled? I have no idea.
Just to be sure of the OPs wording, after it's topped up to five gallons if that's your batch size (I actually mix with a spoon at this point). And like the above poster said, before adding the yeast.
 
And if you forget... after you pitch will get you close. Don’t ask me how I know.
Don’t forget to take notes on your recipe sheet. Date, any changes, you know, all the things you are going to wish you had written down.
Cheers
 
True best practice is to measure gravity at multiple points of your process. I measure two or three times during mash, at first run, second run, pre-boil, during boil (not always but when I feel I am off target for my desired OG), and then again at post-boil (cooled) for OG.
 
If it's an extract batch, you can figure OG by the ppg rating of your extract and specialty grains, if any. You'll need to know the total volume accurately. If you've topped off with water, it will be really hard to get it mixed well enough to get an accurate reading. I feel that the calculated OG is more reliable. Less handling of the cooled wort is also a plus.
 
True best practice is to measure gravity at multiple points of your process. I measure two or three times during mash, at first run, second run, pre-boil, during boil (not always but when I feel I am off target for my desired OG), and then again at post-boil (cooled) for OG.
Best practice ...if you brew professionally?

I'm not sure what 8 gravity readings on brew day would help me accomplish. Could you elaborate on this please?
 
Best practice ...if you brew professionally?

I'm not sure what 8 gravity readings on brew day would help me accomplish. Could you elaborate on this please?

No, not professionally, but as a homebrewer who is working with new recipes and/or trying to get to know their system, I think it is important. Everyone has their own system and things they find important. For me, I like to take lots of readings to keep en eye on how things are going while I am brewing, especially on recipes I have never done or only done a couple of times. IT gives me a baseline for the next time I brew it and eventually I should have confidence without so many readings.

It also allows you the ability to make adjustments throughout your brew day if things aren't going like they should. If I monitor my mash readings and I am falling short on my expected gravity readings I can let it rest longer until I get there, or on the other hand, if I hit it early, I can start the next steps. Same goes for all of the other readings. I maybe shouldn't have been so brazen to use the words "best practice", but for a new brewer who is learning eveything, I think it is beneficial to have this information.
 
One pre-boil gravity could tell whether additional boiling (or added DME/sugar) is needed to increase gravity.
One post-boil gravity will tell whether additional water is needed to decrease gravity.
I'm really not sure why I'd need more readings.

I have good accuracy with just the single post-boil reading.
Agree to disagree I guess.
Cheers.
 
One pre-boil gravity could tell whether additional boiling (or added DME/sugar) is needed to increase gravity.
One post-boil gravity will tell whether additional water is needed to decrease gravity.
I'm really not sure why I'd need more readings.

I have good accuracy with just the single post-boil reading.
Agree to disagree I guess.
Cheers.

I am not saying my method is the best but it is what works for me and I believe there is value in monitoring throughout the process for new brewers. If what you do works for you, that's great. For me, knowing where I am at throughout my process has value and over time I am able to know exaclty where I am at each brew day without so many readings because I have zero'd in on the process.
 
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