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How to Use a Refractometer

How to Use a Refractometer

Having your own refractometer is a necessity when you begin harvesting salable honey. With it, you can be certain you are selling a product that meets the recommended guidelines to prevent fermentation.

The most important factor in using a refractometer is to verify that the unit is calibrated; if not, follow the instructions provided to calibrate it prior to testing. Note: The unit should say whether it’s calibrated or not on the packaging. It isn’t hard to recalibrate. This can be done with extra virgin olive oil if you don’t want to purchase calibration oil as stated on the directions.

Directions for testing your honey:

  1. Place the refractometer in the same room as the honey for at least an hour so they will become the same temperature. This can affect the reading.
  2. Lift the plastic cover and verify that the glass plate is dry, clean, and lint free.
  3. Place a small drop of honey on the glass (a toothpick works well as a dropper; too much honey on the glass will “fog” the reading, making it hard to read).
  4. Close the plastic cover over the honey sample.
  5. Hold the refractometer up to a light source and read the measurement under the column "water %." This will be the line where the blue meets the white. A reading of under 19% is considered OK. Over 19%, fermentation is more likely to occur.
  6. Clean the honey off the glass and the plastic cover with a soft, damp rag, then dry them thoroughly for storing.

When looking inside of a refractometer, three columns are typically visible. The one on the far right side of this particular device (some are different), it shows the "water %." This is the column you are looking for. As you can see in this image, the honey sample is right on the mark at 18.6%. You can also see that the blue line where it meets the white is fairly clear and concise. If that line is fuzzy, you have too little honey on the glass being sampled. Wipe it clean and start over with a smaller sample of honey.

For best visibility, hold it up to a bright light or a window if it's sunny outside.

This refractometer combines affordability with high quality accuracy! Measures moisture from 12%-27% and works in any strong light. This refractometer comes precalibrated and features a rubber grip and comfortable eyepiece.

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