best way to get a gravity sample post boil?

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arborman

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Whats the best way to get a gravity sample post boil? Will all the wort in the kettle give me the same reading after I have chilled it, or does it need to be stirred a bit to get it even?
 
I usually take a reading near the end of the boil just to make sure it's where it is supposed to be. I take out 1 cup, cool it in a small stainless steel bowl set inside a larger stainless steel bowl filled with ice water and it is down to 60 in less than a minute. Shouldn't need to be stirred after it is chilled... though you could always wait till after you aerate it to make sure...
 
Thanks for the advice.. So, what I ended up doing was just drop my thief (sanitized) in the kettle when I had it down to around 70.

My OG was supposed to have been 1.064, but I got a reading of 1.045. How could I have been this low? It was my first all grain batch, not sure if that has anything to do with this, but I will be bummed if this really is the gravity. Any ideas?


My gravity pre boil came in at 1.049 in about 8 gallons of wort. Based on the calcs I did, the efficiency came out to 82.37, or 30.7 PPG. Do these numbers jive with my OG? Is it possible the OG reading is not correct?
 
One of the readings is incorrect, either pre-boil or post-boil is way off. Now way the gravity would go down during the boil.
 
One of the readings is incorrect, either pre-boil or post-boil is way off. Now way the gravity would go down during the boil.

Thats good news.... I had a feeling my post boil gravity was way off. I was pretty certain I read the hydrometer right both pre and post, but I have had similar issues post boil with readings. I did get lots of sediment into my reading jar post boil, could that of had anything to do with it?
 
Your pre boil gravity of 49 should have brought you close to 60 or so... depending on how much you boil off. Some just continue to boil until they reach their goal (67), and some just add DME to make up the difference. Lots of variables in the mix... crush, mash temp, sparge technique etc. It gets easier once you get used to your specific system. Good job so far.
 
A refractometer - about $30 On Amazon - is a great way to get all your pre fermentation gravity readings. Need about a quarter teaspoon sample. Pick it up with a medicine dropper from the boil or a sanitized medicine dropper or spoon post chill. Some temperature dependence but the sample is so small that temp equal rates to room temp very quickly.
 
I usually sample during the transfer. There is no need to stir for the reading because the entire time your wort was boiling convection constantly stirred it. The break will precipitate down and you don't want to read that anyways. After cooling, I use an autosiphon and send the first portion into my sample tube for my hydrometer. Of course, Now I have refractomer (best investment I made for brewing ease) and simply place a couple drops on the collection pane.
 
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