New to using a refractometer

[billsea]

I am making a batch of Welches wine and I am trying to adjust the sugar to get to a good specific gravity. I am new to using a refractometer.

When I use the hydrometer it measures 1.107 and on the other side of the hydrometer there is also a Brix scale which says it is about 25.

When I use the refractometer it also measures about 25 Brix but the scale on the refractometer says that the specific gravity is 1.097.

I think that the hydrometer is probably correct. I would like to use the refractometer more in the future because it is easier, but not if I can't understand what specific gravity scale is saying.

Can anybody help me clear this up?

 

[Yooper]

I am making a batch of Welches wine and I am trying to adjust the sugar to get to a good specific gravity. I am new to using a refractometer.

When I use the hydrometer it measures 1.107 and on the other side of the hydrometer there is also a Brix scale which says it is about 25.

When I use the refractometer it also measures about 25 Brix but the scale on the refractometer says that the specific gravity is 1.097.

I think that the hydrometer is probably correct. I would like to use the refractometer more in the future because it is easier, but not if I can't understand what specific gravity scale is saying.

Can anybody help me clear this up?

Sure- ignore that SG scale on the right- it's not accurate. Use the brix, and then use a calculator to get the SG from that.

But first- calibrate both the refractometer and the hydrometer. Use a drop of water, and make sure the refractometer reads exactly 0. Adjust the screw if needed, to make sure it is at 0. Then, check water with the hydrometer to make sure it reads 0.

Once you do that, use a sugar solution of a known SG. For example, use 1/4 pound sugar (by weight) for 1 quart water. That should be 1.046. Check with both instruments. If they differ, see which is right. Then you can see which is correct and make sure you know if they aren't calibrated together.

 

[Roycebarrow]

Sure- ignore that SG scale on the right- it's not accurate. Use the brix, and then use a calculator to get the SG from that.

But first- calibrate both the refractometer and the hydrometer. Use a drop of water, and make sure the refractometer reads exactly 0. Adjust the screw if needed, to make sure it is at 0. Then, check water with the hydrometer to make sure it reads 0.

Once you do that, use a sugar solution of a known SG. For example, use 1/4 pound sugar (by weight) for 1 quart water. That should be 1.046. Check with both instruments. If they differ, see which is right. Then you can see which is correct and make sure you know if they aren't calibrated together.

Skills Yooper....skills

 

[billsea]

OK, thanks. I have already used the screw to zero the scale, and I will do the 1/4 pound sugar thing.

I will ignore the specific gravity scale on the refractometer, but why in the heck is it even there?

 

[Chef-Ryan]

please Note if using once fermentation has begun, refractometers are no longer accurate since the alcohol refracts the light differently than must or juice

 

[Yooper]

I will ignore the specific gravity scale on the refractometer, but why in the heck is it even there?

Honestly? To sell more refractometers to homebrewers.

Many old winemakers (like me) "think" in brix or plato, but homebrewers usually "think" in SG, so they put the scale on those about 7-8 years ago.

The thing is, it's not too bad at lower SGs, but since it's not linear, when you get above about 1.060 or something, it's not accurate at all.

When you're checking, a very check guestimate is to multiply the brix by 4, and that's pretty good until you get to the higher gravity wines/beers.

For example, if I'm checking the gravity, and it's 12.2 brix, I say, "Oh, 1.048", and it's really close. 20 brix is darn close to 1.080. Once you get to 25 brix or thereabouts is when the difference is more noticeable and starts to diverge.

 

[billsea]

I found several conversion tables on line that convert Brix to specific gravity.
They all agree and also agree with Brix and specific gravity readings on my hydrometer. It appears that the conversion used on the refractometer is just plain wrong.

On amazon I found a different refractometer and the scale shown appears to be correct with all of the other tables. I ordered one. If the scale is as shown I will keep it and throw away the bad one.

It will keep my poor feeble mind from getting confused.

 

[jgmillr1]

Also keep in mind that the hydrometer measurement is very sensitive to the temperature of the liquid. The instrument should come with information on what temperature it was calibrated to and you will need to adjust your reading if the temperature is different. This is one reason why I prefer the refractometer since you are only using a couple drops of liquid and it will quickly adjust to the temp of the refractometer instrument.

While the refractometer does not correctly report the actual sugar level once fermentation has started, it can be used to monitor the fermentation progress and look for when the reading stabilizes. My wines will usually read 5.5-8 brix on the refractometer once the fermentation is complete. The final value varies between wines and depends on many factors including yeast selection, acidity, and starting brix.

 

[bruhaha]

I use a prism refractomer, a floating hydrometer and a Milwaukee digital refractometer.

I did some calibrations to ensure they were all together before using. All temps taken were at 60F where the hydrometer was calibrated. I started by reading distilled water. My hydrometer read dead on 1.000 so I was good to use that instrument as a baseline. I zeroed both refractometers with distilled water to read zero.

My next test was a "Wort Correction Factor". I used 2 ounces of DME dissolved in 8 ounces of distilled water. Since I knew the floating hydrometer was dead on, I read the 60F wort to be 1.075. Then, when reading with the refractometers I converted to Brix. Neither was exactly 1.075 so I ended up with a very slight WCF of 1.02 for one and 1.03 for the other. This makes things more precise if you are so inclined to go to this trouble. In all reality at the home brew level...its almost a so what.