Uh oh! I made an error on reading my original SG!

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bstnh1

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My POV is pessimism. If I get an odd reading, I always assume I made a mistake and check again. 🙂

When starting a red wine or any fruit with lots of pulp, I make 3 checks in different parts of the must. If my readings differ by more than a point, I stir, then check again. The drill-mounted stirring rod makes this much easier.

I use a FermTech wine thief, which is wide enough internally to hold a hydrometer. I keep it clean and sanitize before use. Withdraw a sample, drop the hydrometer in, and take the reading. Sometimes I have to spin the thief to dislodge bubbles and/or to get the hydrometer away from the sides. Yeah, that can sometimes be a pain. When done, there is a pin on the bottom of the thief -- press that against the side of the fermenter or the inside of the carboy mouth, and the wine drains back in. This makes drawing the sample easy and it greatly reduces air contact.

Note -- this works great on carboys and barrels, but 4 liter jugs usually have too narrow of a mouth to fit.

Here is one source: Fermtech Wine Thief
My Fermtech wine thief drips when it's full.
 

winemaker81

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My Fermtech wine thief drips when it's full.
Run the tap and turn the thief upside down into the stream. I've had "chunks" caught in mine and had to clean it out.

When I pull it out of the wine I'll get 3 to 10 drops, which I attribute to wine not inside. I hold the thief over the container for 5 or 10 seconds, until it stops dripping.
 

BernardSmith

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But here's the other thought: treat any actual reading you take as likely an error UNTIL you can confirm that it is not, if the reading does not make good sense given informal ballpark estimations you are also using in parallel. In other words, if you expect that a wine kit SHOULD read 1.090 (more or less) but your reading is 1.150. Is the volume right? If it is and the reading is so far off from the "calculated" reading, then suspect your reading. In my opinion always, always know what reading to expect BEFORE you measure the gravity. If your actual reading is more or less what you would anticipate then it's OK. If it's far out then suspect your reading. For instance, I just started a micro batch of a hopped mead last night using 2.5 lbs of honey to make 1 gallon of must. I had boiled about half a gallon of the water with some hops for 30 minutes and so expected that some of that water would have evaporated and a small amount of the water would have been lost when I strained the now water-saturated hops.Two and a half pounds of honey in water to make 1 gallon would raise the gravity of the water by about 87 points (to 1.087+/-) and my actual reading was about 1.095. Makes good sense if the total volume is a little less than 1 gallon.

Bottom line, be like a lawyer: always know the likely reading of any metric you measure BEFORE you take the reading, and if the actual reading is very different question the reading because it has to be wrong for some reason. It's the reading that has to be wrong and not if you do the calculations correctly, your estimation that is wrong.
 

Jim Welch

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I use a refractometer to check original gravity and monitor fermentation progress. I know what you're thinking- refractometers are skewed by the presence of alcohol and are not accurate after fermentation has started. And you are correct!
Morewinemaking.com has a spreadsheet that corrects these active fermentation refractometer readings and I have confirmed many times (with a hydrometer) that it is quite accurate. Throughout most of fermentation it is usually dead on or 0.001 off, which in my estimation is plenty accurate for monitoring fermentation progress, especially if you add yeast nutrients at 1/3 sugar depletion. It does seem to be several points off as the wine nears the end of fermentation though so I do confirm with a hydrometer.
Once the spreadsheet tells me I'm below 1.000 I get the sanitized thief, hydrometer, and hydrometer tube out and confirm the reading. I find it makes it quick and easy to get a gravity reading every time I stir/punch down. Just let 4 drops fall on the refractometer from my stir paddle and take a reading, plug it into the spreadsheet and I know right about where the fermentation progress stands.
If you have a spreadsheet program like Excel or another one on your computer you can check it out.
 

Scooter68

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I don't watch TV and watch very few movies but I will try to remember that one.

Actually the movie is on Amazon and along with another movie the two provide great looks into wine making. The second movie "Bottle Shock" is based on the true story of how California wines rose to world renown.
 

Noontime

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I agree! Wine/O2 interaction appears to be a commonly misunderstood topic. We see a lot of beginners terrified that their wine will have air contact.

During and shortly after fermentation, wine is emitting sooooo much CO2 that O2 doesn't really have a chance. This is among the reasons that when using kieselsol/chitosan immediately after manual degassing, I have no fear of leaving the wine in an open bucket (covered by a towel) for 1 hour between adding kieselsol and the chitosan.

After that? When the wine is not emitting a self-protecting amount of CO2, I keep the air contact to a minimum. This is when a good wine thief and top-notch hygiene are critical.
So agree with winemaker81... it is sooo common to see people with a little bit of accurate information extrapolate that into bad ideas and advice. Only during active fermentation is wine NOT at risk of oxidation because it's saturated with CO2, and ONLY while the yeast is building the initial colony (before and at the beginning of active fermentation) does it require small amounts of O2 (and for frick's sake it does NOT need to be actively exposed to O2 for that). :)
 

Ivywoods

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During fermentation I don't worry much about exposiing the wine to the air. It's got a lot of CO2 in it then so I figure as long as I don't do something silly like leave the cloth off the bucket or fail to airlock the carboy it should be fine for that short time it takes to put it into testing tube.

For grins try watching movie From the Vine and they show wine making (fermenting) in open vats. Just a "little different" from our techiniques. ;)
I watched the movie. I enjoyed it.
 

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