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Refractometer DiFluid R2

Keep your coffee brewing under control. No more shooting from the hip. The refractometer will always guide you to delicious coffee. An improved more accurate version of the DiFluid refractometer that came with an affordable variant.

Refractometer DiFluid R2

Last pieces available
Your price (Incl. VAT)
6 000 Kč
Manufacturer Digitizing Fluid Technology Co (Hong Kong)
Color Black
Dimensions 88 mm x 36 mm x 16 mm

What is a refractometer?

A refractometer is a device which determines the amount of dissolved solids (TDS) based on the refraction of light as it passes through a liquid. Simply put, how concentrated the coffee is. Once we know the TDS value, we are able to calculate the extraction yield, i.e. how much coffee we were able to use. The coffee bean contains about 30% soluble substances and the rest is cellulose. The ideal extraction is between 20 and 25%.

What will it tell us?

Coffee brewing - the refractometer is a useful helper when setting the recipe for espresso and filtered coffee.
Wrong setting of the grinder - commonly, the refractometer can help determine, if your grinding is fine enough. Low extraction yield can indicate that you grind your coffee too coarse for your particular method.
Grinding burrs - consistently low extraction below 20% may indicate that the burrs in the grinder are worn and need to be replaced.
Roasting - within one coffee we can determine how well the coffee is roasted. If it is extracted well or if it is a problem to achieve optimal values for a certain batch.


We tested the refractometer in our cafes and compared the results with the VST LAB refractometer, which is six times more expensive. The measurements did not differ from each other or with negligible variation. For greater accuracy, it is necessary to regularly calibrate the refractometer with distilled water and measure a cold coffee sample.

3 modes

1. Simple measurement
2. Automatic repeated measurement (up to 10)
3. Automatic sample detection and start of measurement

Who is it intended for?

For every coffee enthusiast who wants to have an overview of how well his coffee preparation is going.
A refractometer should be mandatory equipment for a cafe that is serious about coffee.

Package contents

Charging cable USB-C
Microfiber cloth

Measurement procedure

1. Turn on the refractometer.
2. Drop distilled water onto the slide.
3. Calibrate the refractometer - press and then press and hold the button.
4. Wipe the slide.
5. Stir the prepared coffee and transfer the sample to the slide with a spoon.
6. Press the button and wait for the measured value.
7. Repeat the measurement until the refractometer repeatedly shows the same value.
8. Pour out the sample and clean the slide.

Enter the measured value into the application. After entering the weight of the coffee used and the weight of the resulting drink, you will get the value of the extraction yield.

Application - download
Application - download
Measurements can also be performed using a paired phone.

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