The Instant Nespresso Experiment

Text: Jan van der Weel

Pictures: Frans Goddijn

James Hoffmann recently wrote a very interesting article about Nespresso. One of his findings was the extreme high extraction yield of Nespresso. Nespresso coffee extracts better on low end equipment than most high quality coffee in combination with high end brewing equipment.

“This is pretty impressive work for 12 seconds of brewing. If you’ve played with things like the EK-43 then your target extraction range probably moves from 18-22% of the Gold Cup standards, up towards maybe 20-24%. If this is your window then a Nespresso capsule hits that window regardless of where you pull it, between about 25g of liquid and about 60g of liquid.”

Nespresso cups opened up to test roast color on the Tonino device

He wrote that there’s a lot speculation about the technology Nespresso uses. That inspired us to read into coffee patents that might explain this phenomenon. Reading these patents made very clear that the coffee industry is technologically very advanced. We saw many interesting coffee patents that are owned by Nestlé, the producer and brand owner of Nespresso. We specifically read the patents that were related to ground & instant coffee coffee. 

A few findings from this small desk research. One Nestlé patent is about the improvement of the aroma and flavour of instant coffee. This can be improved by spraying an aroma containing substrate to instant coffee. The patent states that it is equally applicable to other beverage powders such as roast and ground coffee powders. Another Nestlé patent is about the improvement of the taste and aroma instant coffee. This can be improved by adding ground coffee to instant coffee. One thing became clear after reading the patents. We don’t have to assume that industrial instant, ground or whole bean coffee is 100% pure. Things might not be as they seem.

Maybe not all of the technology that Nespresso uses can be found in patents. After reading the patents and rereading the James Hoffmann article a very simple idea popped up in our minds.

Maybe Nespresso is adding instant coffee to the Nespresso cups to increase the extraction yield?

This idea is so simple that it could be easily tested. Two days later we did an experiment to test this hypothesis.

We made a few assumptions for the experiment. First we thought that ground coffee would be very difficult to extract in cold water (room temperature). Secondly we assumed that instant coffee would be easy to extract in cold water. By diluting regular ground and Nespresso coffee and comparing the extraction yields we would be able to check if we were on to something. We also checked the extraction yield of instant coffee, to check our second assumption.

To be sure that all of our samples would be properly mixed and measured, we would put them in the laboratory centrifuge.

We needed Nespresso, regular ground coffee and instant coffee for the experiment.  We decided to use Nespresso coffee that was supposed to be lightly roasted. The sales person of the Nespresso Boutique in Amsterdam’s PC Hooftstraat advised us to try the Nespresso Cosi. My girlfriend Aura and I sipped the coffee and we both agreed that it tasted like lightly roasted coffee and that it matched the advertised flavour profile.

Pure, lightly roasted East African, Central and South American Arabicas make Cosi a light-bodied espresso with refreshing citrus notes.

Besides Nespresso I bought a package of Nescafe instant espresso coffee at the local supermarket. The other coffee we used was an Ethiopian Limu roasted by the Dutch Bocca coffee roasters. For the experiment we used filtered water with a TDS of 260. Extraction yields were calculated by using a 4th Generation VST LAB Coffee Refractometer and the VST CoffeeTools android app.

Nespresso grounds ready to test

Before diluting the three coffees in water we first measured the color of the coffee with the Tonino color meter. This gave some unexpected results. When measuring the Nespresso Cosi the display showed a score of 31. This scores means that the Tonino color meter ‘sees’ a very dark roast instead of a light roast.

31 points on the Tonino roast color analysis device

This was rather strange. What makes a light Nespresso roast to look like a very dark roast? The Nescafe roast scored 86 points on the Tonino. That score equals a medium light roast.

Nescafe solids ready for color analysis

86 points on the Tonino

What makes this light Nespresso roast look like a very dark roast?

Next was the preparation of the samples. We prepared 7 samples. The first two samples were made by diluting Nespresso with cold water. The first sample was shaken and the second was stirred. We wanted to know what method gave the best extraction yield. The best method would be used in the preparation of the following samples.

Weighing off Nespresso grinds

Sample shaken, not stirred, ready to centrifuge

Coffee sample centrifuge at work

Out of the centrifuge

The other samples consisted of diluted Nescafe Espresso and diluted ground coffee. We made three samples of ground coffee with a different coarseness. In table ‘results experiment’ you can see the results of the experiment. The results do confirm that you can easily make coffee from instant coffee and cold water. The results also show that by stirring and centrifuging finely ground coffee you can extract up to 14.5% from the grounds. This was really something we had not expected. We thought that this value would have been much lower.

VSTlabs refractometry

Stirred sample

This experiment does however not show that there is instant coffee in Nespresso.

Table: results experiment

Sample	Coffee	Dry coffee weight (gr)	Water (gr)	Mixing method	Measured TDS	Extraction Yield
1	Nespresso Cosi	1.32	7.19	Shaken	2.28	7.74%
2	Nespresso Cosi	1.33	7.21	Stirred	3.43	11.64%
3	Nescafe Espresso 100% Arabica	0.54	8.03	Stirred	5.64	95.18%
4	Nescafe Espresso 100% Arabica	1.33	7.24	Stirred	14.36	89.74%
5	Limu (Bocca Coffee Roasters), espresso ground	1.31	7.28	Stirred	3.27	12.27%
6	Limu (Bocca Coffee Roasters), finer ground	1.32	7.22	Stirred	3.63	14.43%
7	Limu (Bocca Coffee Roasters), even finer ground	1.32	7.3	Stirred	3.78	15.51%

Samples

Samples of Bocca roasts out of centrifuge

Nescafe samples

Conclusions

The experiment did not show that there’s instant coffee in Nespresso. The experiment however did show some remarkable results. At first we find it rather strange that the color meter measured lightly roasted Nespresso as dark roasted coffee. We can not explain this phenomenon.

Secondly this experiment shows that ground coffee seems to be quite easily extractable by stirring and centrifuging. Maybe the process of making a cold brew coffee can be sped up by such a kind of method. Maybe this is worth further investigation. Centrifugal brewing is something that has been done in the past. Douwe Egberts has even made a cheap home espresso machine that was built upon this principle.

The experiment shows that ground coffee seems to be quite easily extractable by stirring and centrifuging.

Thirdly the experiment seems to indicate that something else is going on. We are looking forward to the upcoming posts by James Hoffmann about Nespresso. Maybe he will be able to explain what’s going on.

Sediment at the bottom of centrifuged Nescafe solution

Nescafe sediment droplet in the sun

Nescafe sediment droplet after some minutes in the sun