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A refractometer (Brix meter) measures the sugar content (Brix) of a solution by detecting the degree of refraction of the light passing through that liquid. They are simple to use and have several important uses for good health. (In our house, if the refractometer is misplaced, we often stop everything to find it.) The main uses for the refractometer are:

  1. Checking the sugar content (in % or degrees Brix) of juice extracted from any produce or milk, which indicates the quality and mineral content of the food
  2. Checking the sugar content of urine for RBTI numbers (general indication of health and guidance for diet protocol)
  3. Urine test to choose an immediate response to symptoms

My preferred source for refractometers is Amazon, where you can get a perfectly acceptable model for under $30. The suggested (the $15 suggested calibration solution is not needed, since distilled water works great for that, and is very affordable.) To use the refractometer, the process is very simple and takes less than a minute.

Refractometer Directions

refract-scalerefract-demoOpen the lens cover and put several drops of the solution on the lens plate. Close the cover and look through the eyepiece. You will need to turn the eyepiece to bring the image of the scale into focus. Read the value according to the line where the white becomes blue. If it is a crisp line, great. If not, first check the lens for bubbles or air pockets. Tapping the cover usually fixes this. For testing urine samples, the most accurate way is to dip the lens and slightly open cover into the sample container. This avoids the use of a dropper, which, if not completely dry on the inside after previous tests (not always easy to achieve), can cause huge inaccuracies in the readings. Record the reading and rinse the lens under running water. Wipe with anything non-linty and leave open to dry completely.

The first time you use the refractometer, the solution on the lens plate needs to be only distilled water and you will need to use the teeny-tiny screwdriver included in the case to adjust the line where white changes to blue to be exactly zero. This is not difficult; the adjustment screw is on the top of the device and is covered by a removable plastic cap. 

I’ll teach you all about the Brix of foods and Brix of urine in other posts, but I think this is everything you need to know to get started with using refractometers!