Tom,

I do not use a refractometer but here a while back I saw a table ore
equation published that related refractometer measurements to alcohol/sugar
mixtures. A hydrometer should not be useable with a water/sugar/alcohol mix
but because people have worked out the relationship you can. I seen no
reason why the same could be done with a refractometer.

Anyway there is such a table out there. You might try to dig it up and see
if you believe it.

Ray

"Tom S" > wrote in message
m...
>
> "WannabeSomeone" > wrote in message
> .. .
>> Yesterday I received my mail order "Distiller's Refractometer" from
>> Homebrew Heaven and I was playing around with it in measuring the alcohol
>> content of some of my store-bought liquor.
>>
>> Then I was thinking "What would my Sugar Brix Refractometer read if I put
>> drops of alcohol on the viewing prism instead of sugary must?". To my
>> surprise, my 40% v/v Gordon's London Dry Gin reads about 14 Brix (about
>> 7.5% potential alcohol). That is totally absurd. I would imagine it would
>> be somewhere below zero.
>>
>> Then I figured that the refractometer was doing everything by the
>> refractive index. Sugar Brix Refractometer is designed to measure sugar
>> content by the refractive index. It should be correct if used on sugary
>> must before fermentation. However, if the sugary must undergoes
>> fermentation and much of the sugar is converted to alcohol, the Sugar
>> Brix Refractometer cannot be relied upon anymore become the refractive
>> index of alcohol in the half-finished wine is messing up the reading. I
>> believe you have to go back to using a conventional floating hydrometer.
>
> That's exactly right. Once the fermentation has begun, your refractometer
> is useless.
>
> Tom S
>