Sous Vide Cooking

Sous Vide Immersion Circulators Review – Part 1

by on Nov.20, 2017, under Equipments & Accessories

Dissna KW802, Vacmaster/Buffalo, Swid Premium, Melissa (Anova Counterfeit), Anova Wifi

My last review of the most known sous vide equipment of the market dates from 2011. In 2009 most immersion circulators were manufactured by Julabo (now German Fusion Chef), Polyscience (USA), Roner (Spain), Clifton Range (UK). All these machines were laboratories equipment used in kitchens. Then the US Sous Vide Supreme and the German Swid (Addelice) were launched as firsts sous vide equipment 100% devoted to sous vide cooking. End 2012 Nomiku started a sous vide project on Kickstarter followed by Sansaire and Anova…After that the Chinese have flooded the market with cheap and low quality products.

If you are interested in a sous vide immersion circulator, just surf on Alibaba, it is probably available for wholesalers at USD 40…you’ll find the same machines sold on internet with dozens of other trademarks at retail price between USD 100 and USD 300.

Example of "quality immersion circulator" Dissna sold on Alibaba at USD 39...

Some friends of mine have purchased different thermal circulators. They borrowed them to me to conduct this test. Unfortunately I couldn’t put a hand on a Sansaire or Nomiku which are not so popular in Europe.

- Anova Wifi: USD 130 to 180. This world-renowned device has been acquired in 2017 by the Electrolux Swedish Cie. Is this device so great?
- Melissa: EUR 80, Anova’s counterfeit available on the European market (no Wifi or Bluetooth). Is it worth saving EUR 80 compared to the Anova?
- Chinese thermostat sold under many trademarks such as Buffalo, Vacmaster, Lacor, Allpax, Steba, Metro…priced between EUR 230 to 300. Let’s call it Buffalo / Vacmaster. This device seems to be popular among professionals who don’t want to invest in an Addelice or Julabo/Fusion Chef. Is it a good strategic choice?
- Dissna KW802 (also sold under other trademarks): EUR 110. A new comer on the market. Is this piece of hardware promising and about to compete with Anova?
- Addelice: the Swid is very popular in Europe among professionals and amateur cooks. It has the reputation being a high performance and user friendly device. Price is high compared to the other devices (Swid EUR 400, Swid Premium 630 excl. VAT), nevertheless, I think it is interesting having a reference for comparison for the purpose of this test.

On this first post I have focused of the heat speed, temperature accuracy and stability. Other tests and information will be disclosed in future posts.

Test 1: Heat Speed

Power of sous vide devices can vary from 800w to 2,400W. Does the manufacturer’s information comply with the technical specifications? Is it worth it to have a lot of power to cook sous vide? What are the advantages and drawbacks?

The purpose of a sous vide device is to heat and stabilize the temperature of a water bath.
If you are an individual and use small containers (less than 10L) you definitely don’t need strong power. Nevertheless, a powerful device can help temperature stability when regulating high temperature (such as 90-95°C for vegetables), even in a middle size container. Drawback: a powerful immersion circulator in a small container can “overshoot” for some minutes. If the temperature controller is good the overshooting should vanish after some minutes.
If you are a professional and use big containers (as from 28L) power is very useful to reach fast the target temperature and stabilize high temperature in big containers up to 58L. For big containers it is essential, even with high power devices to, at least, insulate your container with a cling film or a custom made lid.

To conduct this test I have used a container filled with 7 litres (1.85 gallons) water only. The container was not insulated and not covered by a lid. Starting temperature was 20°C (68°F) and set temperature 55°C (131°F).

- Without any surprise the Swid (2,400W) is the fastest device. It took 7 minutes only to reach the target temperature.
- The Buffalo / Vacmaster took approx. 55% more time (11 minutes) compared to the Swid. Therefore we could estimate its power to approx. 1,300W.
- Anova took 24′. Compared to the Swid the Anova should be rated 700W (official specifications 800 to 900W).
- Melissa, the counterfeit Anova, took almost as long as the Anova, which is consistent with the 800W specifications.
- Dissna KW802 took 15′, then should be rated approx. 1,120W which is consistent with official specifications. I had some problems to assess the Dissna’s exact heating time. Indeed the temperature displayed on the immersion circulator and the actual temperature in the water bath are not fitting during the heating process. Dissna stopped heating full power at 52°C (while displaying 55°C on its display) and took really long to regulate until 55°C. Then I have done again the same tests but set the target temperature at 58°C. This way I could assess the real time needed to reach 55°C.

Test 2: Temperature Accuracy

Accuracy of the temperature is key for sous vide cooking. 1°C (1.8°F) of inaccuracy can have a great impact on the final result of a recipe! Most immersion circulator’s users don’t realise a sous vide equipment can become inaccurate after a while. Some times an immersion circulator can be inaccurate out of the box! To test the accuracy of an immersion circulator you need a very special thermometer. I have used a Greisinger GMH 3750 with accuracy ± 0.03°C and a Pt100 probe DIN B ± 0.10°C. This device, together with its probe cost approx. EUR 380! Just to say that you can trust in the accuracy of my temperature measuring.
If you make your own test with your immersion circulator and thermometer, you may find different results for the reasons as follow:

- Your thermometer probably sucks! Sorry but many people are relying on their digital thermometer without looking at specifications. I give you one example: This very classic kitchen thermometer is ranked with an accuracy of ± 1°C (± 1°.8°F which is already bad)! But this information is not enough. You need both the accuracy of the thermometer AND the accuracy of the probe. One data is missing, which means this thermometer can be even more inaccurate…
In addition, thermocouple type K thermometers can become inaccurate after some years. Professionals usually make them be calibrated each one or two years.

- For example a manufacturer indicates ± 0.3°C accuracy for his immersion circulator. Which means my device can be + 0.3°C off when yours can be – 0.3°C off, which is totally normal.

The above chart speaks for itself.

- Dissna KW802 circulator was the worst device tested. No comment!
- Melissa, Anova’s counterfeit, got an unacceptable accuracy above 67°C.
- Anova was very good until 80°C.
- Vacmaster / Buffalo Chinese machine was excellent until 80°C and acceptable until 90°C
- The Swid accuracy was excellent at all temperatures. We could not measure the accuracy above 90°C as the Swid can’t be set above 90°C. We asked Addelice why. Addelice said all Swids could set temperature up to 95°C as from mid 2018. In the meantime the Swid can be ordered with 95°C specification, on request. Addelice confirmed accuracy should remain excellent at 95°C.

Test 3: Temperature Stability

The “stability” criteria is the capability for an immersion circulator to regulate the temperature of a water bath which can be affected by external factors like an open window nearby the water bath container, or immersing 5°C pouches in the water bath…
Usually, stability of immersion circulators isn’t an issue.
I have used the Greisinger thermometer to check the temperature stability. The resolution of this thermometer is of hundredth of a degree and its display is refreshed each half second.

- Addelice Swid is very stable.
- Anova is very stable.
- Vacmaster / Buffalo stability is ok although confusing. The temperature stability of the water bath (checked with my thermometer) is ok but the temperature on the display of the Vacmaster circulator is constantly fluctuating of ± 0.2°C.
- Dissna KW802 stability is less good compared to the Vacstar / Buffalo / Allpax and suffer from the same “issue” than the Vacstar device. Fluctuating on the circulator display can raise up to + 0.3°C.
- Melissa (fake Anova): I was flabbergasted! I never thought a manufacturer could cheat that way! As soon as the set temperature is reached, the software of the immersion circulator freezes the display. In other words, if you drop ice cubes in the water bath you will not see any changes on the display…

:, , , , , , , , , , , , ,

Leave a Reply


− three = 3

Looking for something?

Use the form below to search the site:

Still not finding what you're looking for? Drop a comment on a post or contact us so we can take care of it!

Visit our friends!

A few highly recommended friends...