concentration(EC) sensor

"I wonder why and how you measure the coffee concentration."

"Real-time coffee electrical conductivity? Concentration?"

Q. Why do you measure coffee electrical conductivity?

A. The best way to evaluate the quality of coffee roasting is 'cupping', but 'color' is an important indicator when it cannot be cupping. The best way to evaluate the quality of coffee extraction is 'tasting', but 'concentration' becomes an important indicator when it cannot be properly tested. It is a very useful way to check the concentration of espresso in a cafe and manage the quality. However, checking the concentration of the extracted coffee in a busy environment can be inconvenient. During extraction, you can measure the change in concentration to estimate whether the final concentration is constant.

Q. During extraction, can you measure the change in the concentration of coffee?

A. Usually, the concentration of coffee is determined by TDS. The most efficient way to measure TDS is to use a refractometer, which cannot measure changes in the concentration of coffee flowing. The most efficient way to quickly measure fluid concentration is to use an 'electrical conductivity sensor'. An electrical conductivity sensor can measure the change in concentration of coffee being extracted.

❊ TDS and electrical conductivity (EC) are not completely replaced. Only a small amount of TDS material has electrical conductivity.  The ratio of the TDS material to the electrically conductive material may vary depending on the type of roasted coffee beans. However, the difference in ratio is not significant, especially the TDS EC ratio of the same coffee beans remains fairly constant. Therefore, it is possible to estimate the change in concentration from the real-time EC graph of the same coffee beans.

Q. How does the concentration (EC) actually change during extraction?

A. If the extraction water passes through all parts of the coffee puck perfectly uniformly, the concentration during extraction will have to continue to drop from highest to lowest. However, concentrations during extraction fluctuate in a very dynamic shape due to biased extraction and various channeling.

Q. How can I use the 'Coffee Concentration (EC) sensor' of Belkafilter?

A. You can set criteria for extraction concentrations and quantitatively evaluate continuous extraction consistency.

In addition, more stable extraction can be continued by checking for abnormal channeling.

TargetIndicatorMeasurement method
Managing extraction consistency
The time it took for coffee extraction to begin
Measure the time from the start of extraction, or from the pressure detection to the EC detection
Managing extraction consistency
Consistency of concentration changes during extraction
Check the slope of the EC graph during extraction
Managing extraction consistency
Consistency of extracted concentrations (beta)
Estimate through changes in EC and flow rate during extraction
Improve extraction quality
Whether there was abnormal channeling
Check the instant fluctuation of the EC during extraction

"Can you show me how to use it?"

"Try extracting it as usual."

Try to extract as consistently as possible with a belkafilter as usual.

If serious channeling occurs, pack the coffee more evenly or adjust settings such as the degree of grinding, pressure, etc. You can see how stable the graph can be.

If serious channeling is reduced through successive attempts, and if the EC graph is reproduced consistently, we can set it based on that EC graph and evaluate the subsequent extraction.

If a large change in the concentration change graph is detected in successive extractions, you can verify extraction consistency by tasting coffee or measuring TDS.

"How is the measurement performance?"

"Please check the accuracy."

Q. Does it really measure consistently just by putting the EC sensor on the running coffee?

A. (It will be updated soon)

Q. It measures real-time concentration in a new way, doesn't it make it less accurate?

A. (It will be updated soon)

Q. If measuring concentrations with EC sensors is really useful, why do most people use TDS refractometers?

A. (It will be updated soon)