As a new home brewer (honeywine) I have heard conflicting views. Some say take your initial reading before adding your yeast, some say after and have heard a few say that it really doesn't matter. In the interest of accuracy what is the general consensus among the veteran brewers ? Thanks. Steve
When is the proper time to take a hydrometer reading?
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The correct (sort of, IMO) theoretical answer would be to take your reading after pitching the yeast. In practice, it won't normally matter much.
If using liquid yeast, it can make a difference, possibly significant, if the original wort and starter liquid have very different gravities and the yeast is pitched along with its large starter volume. If you measure after pitching, it will be "correct," but that starter wort contains ethanol as well as water. It also contains a lot of suspended yeast (of course). So the ABV formulae that rely on the OG number being based on sugars/dextrins dissolved/suspended in water (and not ethanol and yeast) won't be quite right. (OTOH, those formulae are only estimates anyway.)
Personally, I measure before pitching and don't worry about it. But I also crash and decant my starters. I would look at it this way:
Dry Yeast: insignificant and unmeasurable
Liquid Yeast from the Pouch: insignificant
From Decanted Starter: insignificant
Undecanted Starter: maybe significant
If using liquid yeast, it can make a difference, possibly significant, if the original wort and starter liquid have very different gravities and the yeast is pitched along with its large starter volume. If you measure after pitching, it will be "correct," but that starter wort contains ethanol as well as water. It also contains a lot of suspended yeast (of course). So the ABV formulae that rely on the OG number being based on sugars/dextrins dissolved/suspended in water (and not ethanol and yeast) won't be quite right. (OTOH, those formulae are only estimates anyway.)
Personally, I measure before pitching and don't worry about it. But I also crash and decant my starters. I would look at it this way:
Dry Yeast: insignificant and unmeasurable
Liquid Yeast from the Pouch: insignificant
From Decanted Starter: insignificant
Undecanted Starter: maybe significant
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Moved to Beginner's.
Right, wrong, or indifferent, I've always taken the OG sample before pitching.
Sometimes I use dry yeast sprinkled on top, somtimes a decanted liquid starter. Either way, for me, not a big matter of concern. I take the sample going from kettle to fermenter and that's the OG I use.
Frankly, (and I'm sure to get a finger wag on this
) if I'm doing an all extract batch, I may not even take an OG sample and just calculate OG based on the volume and points from the fermentables.
Sometimes I use dry yeast sprinkled on top, somtimes a decanted liquid starter. Either way, for me, not a big matter of concern. I take the sample going from kettle to fermenter and that's the OG I use.
Frankly, (and I'm sure to get a finger wag on this
) if I'm doing an all extract batch, I may not even take an OG sample and just calculate OG based on the volume and points from the fermentables.
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Pick one and make it a habit. I don't see any reason why it should matter. Other than if you add a lot of liquid yeast or re-hydrated dry yeast then take a SG reading, you might be a little further away from your recipes predicted OG.
But unless a point or two is going to bother you, then it's a small concern.
But unless a point or two is going to bother you, then it's a small concern.
If I'm pitching into 5 gallons with a starter, the starter is generally going to be somewhere around a quart after pouring the clear liquid off. So that's 5% of the total volume. It will increase the gravity, but not much, and a lot of the increase comes from stuff I'm not going to keg. If what you're pitching is mostly yeast, it's going to settle in the fermenter eventually, and that will greatly reduce its influence on gravity readings, so is there any point in measuring after pitching? I don't think anyone shakes a fermenter to put yeast and crud into suspension to get a truly accurate reading.
This is one of those things I wish I had never been confronted with, because I make perfectly good beer measuring my OG after the boil and before the pitch. I don't use starters unless I have to these days, so I guess the whole question is not very important to me.
There is a ton of bad math and approximation in brewing, because no matter how much we try to turn it into engineering and science, it's still an art. If you get good results, don't drive yourself crazy trying to be rigorous.
This is one of those things I wish I had never been confronted with, because I make perfectly good beer measuring my OG after the boil and before the pitch. I don't use starters unless I have to these days, so I guess the whole question is not very important to me.
There is a ton of bad math and approximation in brewing, because no matter how much we try to turn it into engineering and science, it's still an art. If you get good results, don't drive yourself crazy trying to be rigorous.
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