how to use a hydrometer for newbies

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how to use hydrometer ( sugar meter )

1) how to use hydrometer ( sugar meter ) - here
2) how to use alcohol meter - here



Reading the Hydrometer:

This reading is an indication of how sweet/dry the wine is.A hydrometer is vital for consistent results in wine making and brewing. A hydrometer will show a high figure at the start of the fermentation and a low figure when the fermentation is finished. It gives a useful indication of the progress of the fermentation. To check that the liquid is fermenting, the SG reading must indicate a lower figure than the previous reading. A reading of SG 1.000 or lower for more than two days indicates that fermentation is at an end.The hydrometer should read SG 1.000 in tap water at 20ºC (68°F). The deviation may amount to 3 units of calibration above or below 1.000. Test the hydrometer and allow for the discrepancy, if any, when testing/measuring the liquid.

To use:

Always sterilize hydrometer and trial jar before use. Do not place in hot water, it may break.

Put sample of liquid to be tested into a trial jar. Lower hydrometer carefully into liquid, spin or shake to remove bubbles sticking to stem. If liquid is still fermenting, bubbles on the hydrometer may cause there ading to be incorrect, in this case remove the hydrometer and shake the sample to remove as much gas as possible. NOTE: TO CONVERT GRAVITY INTO BALLINGS PLEASE USE TABLE

When the hydrometer is steady in the liquid take the SG reading from where the surface of the liquid meets the stem at eye level. After use, rinse the hydrometer and wipedry.

Always take a reading of the liquid before adding yeast and fermentation starts. With kit wines it is convenient to take a reading after sugar (if any) has been added. It is best to dissolve sugar before adding, with country or fruit wines take a reading before adding sugar in order to calculate the correct amount of sugar to add.

Beer makers use the hydrometer in the same manner as for wine making, but can use the SG 1.005 point to check when the beer is ready for bottling.

The hydrometer "reads" the thickness of the liquid, if a lot of fruit is used and grain also is added this will increase the reading, the reading can be used in conjunction with a taste of the sample of liquid being tested.

To calculate the final strength of the wine, write down(omitting the decimal point) the SG

At the start of the ferment (i.e. after the sugar was added).Subtract from it the final SG, and divide the answer by 7.36; that is the percentage of alcohol by volume of your wine. Multiply that by 7 and divide by4 and it will give you the strength as proof spirit.

Starting SG – Final SG ÷7.36 = % Alcohol by volume then

% Alcohol by volume x 7 ÷ 4 = Strength as proof spirit
 
Recently someone posted to the board a strange issue - their SG reading actually went UP not down after a few days. After several questions and folks offering various ideas one key point was brought up. And active fermentation is producing a lot of CO2 gas. Not as much fresh soda pop but a lot none-the-less. As a result a hydrometer left in a fermentation bucket or even left in testing tube for a bit of time can collect a lot of CO2 bubbles and produce a false reading. Not at all unlike that glass, can or bottle of soda pop will push a straw up in the air as the CO2 in it gathers on the straw.

Now there's obvliously a big difference in the weight of straw and a hydrometer certainly but on the other hand a hydrometer has a lot more surface area in the bulb and it only takes a few fractions of an inch to change your reading significantly. Let's say your hydrometer rises 1/4" - that's a lot but recently I watched mine climb more than a 1/16 of an inch in less than 10 seconds - So it rises 1/4" and that translates to a reading that should have been say 1.038 instead reads out at 1.050 WHOA! I took a reading last night and I was at 1.044 you say - NOW it's gone up .006? Well that's what a CO2 could do to your reading.

SO - When you take that reading I would suggest you start of course with a clean sanitized Hydrometer. Lower it into your wine must sampling tube and be ready to read it quickly if your fermentation is an active one. Just for sure you might give it a spin to shake off any CO2 bubbles but read soon, don't do like I did an walk away to get your reading glasses in the other room and then come back. You might be rudely surprised.

(This also suggests that those who want to leave their hydrometer in their fermentation container run the risk of false readings unless they remove the hydrometer before taking that reading - that then would be counter-productive to what some have stated are reasons for leaving the hydrometer in the container to begin with.)
 
Just took a reading on day seven of fermentation SG =1.000 pH=3.3
Advice?

You need to start a new thread with this question - Include details about your wine to include type, original SG reading, temps, etc. The more info you provide the better the quality of the answers you will receive. This thread exist to help new folks learn how to read a hydrometer. Interpretation of the readings depends on the wine and a variety of other details.
 
Thanks Jim, nice job. Also always recommend to have a spare one or two on hand. They break easy and roll off things.
 
I tested my current hydrometer in distilled water. I gave me a reading of .996 several times. Temp is about 74 degrees F . Do hydrometers change?. Also, I started a kit a few days back and took the Sg as 1.080. I added a couple of cups sugar/water syrup and brought the SG up to 1.085. So, if .996=SG of 1.000 then a Sg of 1.080 actually = 1.084. Addition of the syrup made it 1.085 which is actually 1.089. Is this correct to your thinking? It's all kind of a moot point, since I plan to ferment it out to dry.
 
I tested my current hydrometer in distilled water. I gave me a reading of .996 several times. Temp is about 74 degrees F . Do hydrometers change?. Also, I started a kit a few days back and took the Sg as 1.080. I added a couple of cups sugar/water syrup and brought the SG up to 1.085. So, if .996=SG of 1.000 then a Sg of 1.080 actually = 1.084. Addition of the syrup made it 1.085 which is actually 1.089. Is this correct to your thinking? It's all kind of a moot point, since I plan to ferment it out to dry.

Don't forget there is also a temperature correction that should be applied to your SG reading. I am going to guess that your hydrometer is calibrated to 60 deg F. So that 0.996 at 74 would really be 0.998 at 60, a delta of just .002. The amount to actually apply at the 1.085 also will depend on the temp of the must when you measured it. If it happened to be 74 deg F, then 1.080 really was 1.082 and you would add that .002 to it to make it 1.084. if it was 68 deg F the actual hydrometer reading would be 1.081.
 
Everything was done at a controlled room temp of 74 degrees. My office is 74 degrees . In the past, with a different hydrometer, it read pretty much 1.000 for distilled water. But that hydrometer has since gone the way that fragile hydrometers so often go. I'm not too worried about this since I'm going to ferment to dry, regardless. This wine smells really nice and when it slows down I will take it down to the storm cellar to age out for 3 or 4 months before bottling.
Thanks for your comments.
Update : I just dug out a brand new hydrometer and tested both in 70 degree distilled water and guess what? There is a .004 Sg difference! the new one reads 1.00 at 70 degrees and the one I have been using reads .996! Just goes to show calibrate your hydrometer and account for any deviation.
 
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ok i want to start a thread on how to use and under stand a hydrometer.
as a relitive newbie, i look at the problem with a different perspective than the more experienced, when i got my first hydrometer, i didn't know crap about it
so i read the directions, and tutoriels, some were good and some were confusing

so this will be a work in process, and i welcome ANY constructive critisim to improve the topic.
View attachment 3211
this is a start, looking at the sg scale. i plan to do another pic relating the other scales as i have time
View attachment 3233
update

jim
Thanks for the pictorial.
Specific and simple is always Best.
 
Look I think if you don't learn or have a hydromenter your missing the whole process.their easy to use simple to take care of and you should always have a back up one.
By all means return your sample back to the fermentation vessel.
Well that's my 2cents
 
Using a completely sanitized hydrometer and test jar do you discard the sample or return it to the bucket.
If it is an all juice bucket I don't even use the test jar, I just sanitize and put directly in the bucket.
 
For Temperature correction I would only do that at the beginning or the end when I'm trying to be exact on my starting SG or when I'm trying to determine if the fermentation is 100% complete. In between it doesn't matter. Even at the beginning... With the volume losses and topping off, you are only going to be getting a 'aim point' for your eventual ABV unless you have a known content of the topping off wine and track exactly the ounces of liquid added. Barring an extremely HOT room temp changes of about .002 in an SG reading are about all you are going to see.
 
hear is the next bit to add, thanks to micha for pointing me in this direction,.

HERE IS THE DIRECTIONS THAT CAME WITH MY HYDROMETER

TRIPLE SCALE BEER AND WINE HYDROMETER, 60 DEGREE F

RANGES SPECIFIC GRAVITY 0.990 TO 1.170
BALLING OR BRIX 0 TO 38% SUGAR BY WEIGHT
POTENTIAL ALCOHOL BY VOLUME 0 TO 20%

A hydrometer measures the weight of a liquid in relation to water, the weight of water on a SPECIFIC GRAVITY scale is expressed as 1.000.
As you add sugar or other soluble solids, the numbers will increase, i.e. 1.010 to 1.020 up to 1.100 and more.
1 cup sugar raises 1 gallon's s.g. by .020 = 1cup raises s.g. from 1.050 to 1.070
5 cups raises 5 gallons' s.g. by .020 = 5 cups raises.g. from 1.040 to1.060

The BALLING or BRIX scale tells you the percentage of sugar by weight.
1 cup sugar raises 5 gallons liquid aproximately 1 degree Brix

The ALCOHOL scale is actually the potential alcohol.
( Just reading the scale will tell you about how much alcohol you can expect from a batch of wine if the must ferments to dry or below 0%. this gives you a ballpark figure to work with. there are to many varables to predict just the exzact amount of alcohol a batch of must will produce, but if everything goes right, it should be close

In order to determine the alcohol content in wine, you need to take two readings.
the first reading is taken before fermentation (before you pitch the yeast).
the second reading is taken after all fermentation has stopped.
Subtract the second reading from the first reading and the result is the potential alcohol

FOR EXAMPLE
1ST READING 12% ( = 1.090 SG)
2ND READING 0% ( = 1.000 SG)
____________________
POTENTIAL ABV 12%

OR

1ST READING 13% (=1.098 SG)
2ND READING 1% (=1.008 SG)
POTENTIAL ABV 12%


TO USE YOUR HYDROMETER:
Put a sample of your must or wine in a hydrometer jar, (or any slim vessel as deep as the hydrometer is tall, and you can see through, many of us just float it in the primary fermenter bucket. i started out using the plastic tube the hydrometer came in.)
then give the hydrometer a spin to dislodge any bubbles .
Then at eye level read the numbers where the liquid cross the stem of the hydrometer.
this figure will tell you how much sugar is in your must and the potential abv.
with these figures you can adjust the sugar according to the style wine you wish to produce.

( YOU WILL ADD SUGAR OR HONEY TO RAISE THE THE POTENTIAL ABV . )

TEMERATURE CORRECTIONS:
This hydrometer gives accurate readings when the temp of the liquid is at 60 degrees.
The following tables show how to correct for temp variations,

TEMP. DEGREES F. SPEC. GRAV. CORRECTION
50............................... SUBTRACT 1/2 EXAMPLE
60.................................................... 0 TEMP OF MUST IS 84
70.............................. ADD............ 1 SP GRAV. IS 1.100
77.............................. ADD ........... 2 CORRECTION FIG IS... .003
84.............................. ADD............ 3 CORRECTED SG IS.... 1.103
95.............................. ADD............ 5

THE ABOVE TABLES ARE NOT REALLY NESSESARY AS THE DIFFERENCE IN THE FINAL RESULTS DOSE NOT AMOUNT TO MUCH.


( THESE NOTES ARE A C/P FROM ANOTHER POST ON ANOTHER FORUM)

These are notes I've written in the back of my Wine Log Book over the years. They're not all exact, but close enough for my use in winemaking. I've gathered them here and there and thought I'd share them. Maybe they'll help someone figure out a batch of wine. Be sure and double check before taking my word for it, in case I'm wrong or make a typing mistake. I know for many of you this will be stuff you already know, but it helped me to have it written in the back of my book. Hope it helps someone else!

SUGAR NOTES

2 oz. (4 TBSP) sugar raises 1 gallon's s.g. by .005
1 cup sugar raises 1 gallon's s.g. by .020
5 cups raises 5 gallons' s.g. by .020
4# sugar = 9.44 cups
1# sugar = 2.36 cups
5# sugar = 11.8 cups
10# sugar = 23.6 cups
1# sugar in 5 gallons liquid will raise Potential Alcohol 1%


Sweetness:
1# sugar = 3 cups corn sugar
4# sugar = 5# honey
3# sugar = 5# raisins
1# sugar = 20 oz. grape concentrate

Using BRIX, % Sugar:
1 cup sugar raises 5 gallons liquid aproximately 1 degree Brix

jim
 
Anybody have any tips for inconsistent readings? I started a banana wine yesterday that gave me two wildly different numbers. Drawing from the bottom of the must gave me 1.140 while drawing from the top gave me 1.090. Is this just banana goop that's settled to the bottom? It was noticeably viscous and had some visible particles suspended in it.

I'm using a nylon straining bag and I added pectolase with my k-meta a day before innoculating. I stirred the must about a minute or so before I took the reading. Only as much sugar as most recipes call for was added - roughly 2lbs for a gallon of wine, thoroughly dissolved in two quarts of hot water. The bananas were also frozen for 36 hours prior to processing.
 
Suggestion: If you can afford it, buy a TILT wireless hydrometer. You calibrate it in distilled water and drop it into your batch. It takes regular temperature corrected readings and lets you instantly read your specific gravity and temperature on your smart phone or iPad.
 
Anybody have any tips for inconsistent readings? I started a banana wine yesterday that gave me two wildly different numbers. Drawing from the bottom of the must gave me 1.140 while drawing from the top gave me 1.090. Is this just banana goop that's settled to the bottom? It was noticeably viscous and had some visible particles suspended in it.

I'm using a nylon straining bag and I added pectolase with my k-meta a day before innoculating. I stirred the must about a minute or so before I took the reading. Only as much sugar as most recipes call for was added - roughly 2lbs for a gallon of wine, thoroughly dissolved in two quarts of hot water. The bananas were also frozen for 36 hours prior to processing.

First off, solids do not affect the SG. Only dissolved elements will. And while you stirred for a minute, it sounds like as though there was still some unmixed sugar water in the bottom. Remember, stirring around and around takes a while to thoroughly mix the must. I jury rigged a stir paddle with a rectangular plate at the bottom. Ten seconds of up and down pretty well gets things mixed. Just a thought.
 
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