Need info on Refractometers

michaelb · Post by **michaelb** » Mon May 30, 2005 6:36 pm

I make beer, mead, and sweet shine. Want to know if one Refractometer
will work for all products? They are quite pricey. If someone with first hand experience could comment. Thanks

The Chemist · Post by **The Chemist** » Tue May 31, 2005 6:23 am

The Labmart has a good quality alcohol refractometer that reads from 0-80%. Of course, if you want to measure above 80% (really anything above about 60%, due to compression of the scale at higher percentage), you'll need a way to accurately dilute the sample before reading. You'll also need a chart to convert percentage by weight, which is what the refractometer reads, to percent by volume--but that's easy to get. I've used one for years: good product, easy to use, accurate within 1%. They're going for $99.00 right now, but I don't know whether they sell to the public or not. Check out http://www.labmart.com onclick="window.open(this.href);return false;" rel="nofollow .

The Chemist · Post by **The Chemist** » Tue May 31, 2005 7:45 am

Sorry, Mackerel, but I have to disagree. I've cross-checked my refractometer (the $99.00 one mentioned) by hydrometer, pycnometer, and GC. It is accurate to the stated 1%. And there are good reasons to use a refractometer: 1) it is not temperate dependent, 2)very small volumes (20 microliters, about one drop) can be measured, allowing for very accurate cuts "on the fly" 3) it's just a cool toy

(not really, it's a very well-made, solid scientific instrument).

Post by **Grayson_Stewart** » Tue May 31, 2005 8:37 am

I've never tried a refractometer before, but then again I don't download ringtones for my cell, watch High Definition TV, or drive to the grocery store using GPS navigation.....and I can accidentally drop and break about 14 hydrometers for every one refractometer

Science is kinda cool, I can determine the proof of my stuff within 1% or 2% on the fly with a thermometer in my vapor path.

Post by **Tater** » Tue May 31, 2005 12:30 pm

I learned to proof by checking the bead.

Guest · Post by **Guest** » Tue May 31, 2005 7:22 pm

1) it is not temperate dependent

The one I use at work comes with a temprature correction chart. The density of the liquid changes with temprature and as the density changes, light is refracted at different angles. We use them at work to check our metal cutting fluid consentration. I am going to ask my boss if I can have one of the old ones we don't use, the instructions say it is for measuring sugar solutions. Does anyone know a good formula to convert Brix to SG? I found a few on the internet, but they are all different, very long, and give slightly different answers.

Guest · Post by **Guest** » Sat Jun 04, 2005 1:27 am

Chemist,

What is the bah-humbug about? Are you mocking my spelling (sorry, I have never been an english major), or the fact that I use a refratometer at work for something besides distilling? Or possibly that I am challenging your word? Well, the chart that I use is less than half/percent brix over its whole correction, so you are right that temp does not matter that much when using a refractometor. Sorry I got you "P"ed off.

The Chemist · Post by **The Chemist** » Sat Jun 04, 2005 2:14 am

Apolgies, guest.

There is a range of refractometers for use in many different applications. I didn't realize that there was one to measure the kind of light oil used in cutting metal.

Post by **Fourway** » Sun Jun 05, 2005 6:20 am

I deleted a post above.

Brett · Post by **Brett** » Wed Jul 20, 2005 5:47 pm

just outa interest could a vinometer be used to test the %. i know there meant for wine n only measure 0-20% but by watering down the alcohol say 1 part alco 4 parts water couldnt an acurrate reading be taken with this cheap device?

Post by **Fourway** » Wed Jul 20, 2005 6:11 pm

not really. vinometers aren't accurate on anything but wine (and they aren't much good on wine).

norcal · Post by **norcal** » Mon Aug 01, 2005 7:15 am

tater wrote:I learned to proof by checking the bead.

Tater,
How do you check the bead? I'v never heard of this method.

I just ordered a spirit hydrometer from brewhaus. Cost was about $20.00. How accurate can I expect this gizmo to be?

Uncle Remus · Post by **Uncle Remus** » Mon Aug 01, 2005 5:12 pm

norcal wrote:
tater wrote:I learned to proof by checking the bead.

I just ordered a spirit hydrometer from brewhaus. Cost was about $20.00. How accurate can I expect this gizmo to be?

Probably about 99% acurate. When I bought mine I checked it with a bottle of store bought vodka at 20 deg C and it read 40%.

Post by **Tater** » Tue Aug 02, 2005 4:21 am

You shake or slap agenst your hand a small jar with product in it and check bubbles that rise to top. You look at there size. Way they lay and how long they last or hold the bead.Take differnt proofs and try it .

norcal · Post by **norcal** » Tue Aug 02, 2005 6:01 am

tater wrote:You shake or slap agenst your hand a small jar with product in it and check bubbles that rise to top. You look at there size. Way they lay and how long they last or hold the bead.Take differnt proofs and try it .

Ok, I remember some one once told me to shake the jar and see if the bubbles stay in the shine for a long time. they said if the bubbles go right out not to drink it. I thought it was because of some toxins or methelethel badsh#*t.
Now that I look at the stuff I just made a few weeks ago, I see what you are saying. At about 90% big bubbles go to the top real fast. At about 40%, Lots of little bubbles stay for a long time. I'll have to practice some more. Hmm, I guess I'll have to make another batch to practice on.

Thanks Tater