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How do you know if your hydrometer is lying to you?

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mtnman68

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When I started this last batch and took my first hydrometer reading and
and got a reading of 1.050, and just before I bottled it I took the last reading. The hydrometer showed a reading of 1.000. Isn't the reading supposed to go up, instead of down? And the hydrometer also showed the alcohol content to be zero.
I used 1 gallon of best choice apple cider, 1/2 pkg of Cider House Select yeast, it fermented for 6 days and then quit, then I did (what ever you call it) changed jars and got ready to bottle it when I remembered to take a reading and got the 1.000 reading. Oh yeah I did add 1/2 cup of brown sugar to the mixture before putting the yeast in. I would like to have at least have 5 or 6 % of alcohol, not zero percent. So what did I do wrong ? If you have any ideas please let me know!

Thanks

mtnman68
 

m00ps

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You can verify the calibration of your hydrometer by testing at room temp water

But you are very confused on the OG/FG relation. FG is always less than OG. The greater the difference, the higher the alcohol content.

I think you are confusing the "potential alcohol %" with the specific gravity readings. Those are really only useful in measuring the OG and gives a general idea what you could expect in terms of %abv. So 1.000 is water, no sugars to ferment. So of course that is going to show 0%
 

BeeDeeEff

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Nope, it is supposed to go down. Alcohol has a lower density than sugar in solution.

What you're reading is on the alcohol is the 'potential' for alcohol which is correlated to initial sugar amount. It wouldn't make sense if your initial reading showed any alcohol at all would it? So how could it go down if it started at zero?
 

Vaughancider

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It's true that the hydrometer should sink lower post fermentation. Think of the beginning product. It's more of a sugary syrup. Syrup is thick and can support more weight. What makes the beginning juice heavy is sugar. That's a good thing because that is what yeast loves to eat! Yeast loves sugar more than bees and ants. The yeast will eat up all the sugar that it can. When the yeast eats the sugar I get happy because the byproduct is Alcohol!
So when the Yeast feast is complete the majority if not all the sugar is gone. No more sugar, leaves a much lighter drink now. That's why the hydrometer sinks lower after fermentation.
A couple points for you to remember as you hopefully continue your cider adventures:
Don't use juice with preservatives. Preservatives inhibit or kill the yeast. No yeast growth no alcohol.
Yeast is amazing! There are some yeasts that will give you a higher alcohol, but will strip the favors more=champagne yeast. Learn about yeast. Different yeast different flavor. Just like bread sour dough yeast and white Italian yeast.
Also, most cider makers in the UK don't own a hydrometer let alone how to use one. They use experience, taste, skill. It's an art form passed down. Have fun!
 

Yooper

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For a rough guess at the alcohol by volume (ABV) content, the basic formula is:

(OG-FG) x 131 = approximate ABV

So, in this case:
(1.050- 1.000) x 131 = approx. 6.55%

The only thing I would caution is that the cider may or may not be done at 1.000. I've seen cider go as low as .990. If there were not several hydrometer readings taken at least a few days apart to ensure the SG wasn't continuing to drop, I'd place those bottle someplace VERY safe, and check one in a few days to ensure that fermentation was indeed finished before bottling.

Not only are they a mess, but bottle bombs can hurt someone.
 
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mtnman68

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Nope, it is supposed to go down. Alcohol has a lower density than sugar in solution.

What you're reading is on the alcohol is the 'potential' for alcohol which is correlated to initial sugar amount. It wouldn't make sense if your initial reading showed any alcohol at all would it? So how could it go down if it started at zero?
Isn't 1.050 higher than 1.000? Well I am really confused now, I just rechecked this batch and according to the potential % of alcohol it showed it to be about 7%, and that is just where I wanted it to be. How ever the hydrometer showed the same as the last time I checked it, the only thing that changed was the % of alcohol. Maybe I am becoming senile in my old age.

Thanks Y'all

mtnman68
 

nettekdl

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To make things easier, just ignore the potential alcohol scale and focus on your specific gravity readings. The higher the gravity of your must, the more sugar it contains. As your must ferments the yeast are consuming the sugars in solution and converting them to alcohol, thus lowering the specific gravity. To find your abv, use either the calculation above from yooper, or use a calculator such as the one on brewers friend
 

worlddivides

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Isn't 1.050 higher than 1.000? Well I am really confused now, I just rechecked this batch and according to the potential % of alcohol it showed it to be about 7%, and that is just where I wanted it to be. How ever the hydrometer showed the same as the last time I checked it, the only thing that changed was the % of alcohol. Maybe I am becoming senile in my old age.

Thanks Y'all

mtnman68
Yes, 1.050 is higher than 1.000. But higher in SUGAR, not alcohol.

1.000 is the "gravity" of water. Sugar is heavier than water, so the more sugar in the liquid, the higher the gravity. Yeast converts sugar into alcohol, so the higher the number, the higher POTENTIAL for alcohol (the more food available to the yeast to convert into alcohol). As the yeast eats the sugar and converts it to alcohol, the gravity drops lower and lower and lower. Alcohol (ethanol) is LIGHTER than water, which is the reason why.

1.000 as a final gravity tells you nothing unless you know the starting gravity. If you start with 1.010 and end with 1.000, you only have 1.3% alcohol, but if you start with 1.110 and end with 1.000, you have 14.4% alcohol. It is important to know both the "original" and "final" gravity if you want to know the percentage of alcohol.

And, as others have said, you can have less than 1.000 since 1.000 is just the specific gravity of water. Many of my ciders, meads, and wines end around 0.997 or 0.995.
 

BeeDeeEff

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Isn't 1.050 higher than 1.000? Well I am really confused now,
Hydrometers show you the specific gravity of the solution, or its density relative to pure water. A reading of 1.050 means that the solution's density is 1.050 times that of pure water.

So when I said it should go down not up, I was replying to your comment below and talking about the density as the heavier sugar solution was replaced with lighter alcohol

The hydrometer showed a reading of 1.000. Isn't the reading supposed to go up, instead of down?
 
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