Tag: External Probe
A month ago I decided to purchase a digital thermomether with a penetration probe. I had a chock when looking at prices on internet. Price for such thermometer is usually in the range from EUR 200 to EUR 400.
Then, when I saw the Thermowoks onlineshop proposing a similarly equipment for approx. USD 110 incl. shipping to Europe…I decided very fast to make a try.
The overall price was :
- MTC, Mini Handheld Thermocouple Meter, Type K : USD 43.
- K Type Fast Response Meat Needle Probe Fitted into MPK ANSI Plug : USD 30.
- Coiled Lead Type K Extension Wire 2 Meter Plug to Socket Ansi Colour Yellow (627-741): USD 19.
- Shipping cost to Europe: approx. USD 20.
Total: USD 110.
My worry was to determine how good this thermometer is. Was it well calibrated? I asked a friend of mine if he could find a precision thermometer in order to compare its precision to the Thermoworks one. Thanks to Bertrand.L I could find someone borrowing me the GMH-3710. He told me he purchased it here for approx? EUR 220 excl. VAT and shipping costs. This is 3 times the price I purchased mine!
I red on internet that temperature accuracy depends of the temperature. In other words, the higher the temperature is, the bigger the risk of inaccuracy could appear.
For the purpose of my test I tried with both the thermomethers to assess the temperature of an apple, a glass of water containeing water at 46°C and 79°C.
My test with an apple that was laying around in kitchen was excellent. The difference in temperature between the 2 thermometers was in the range from 0.1°C to 0.2°C only. Therefore the inside temperature of the apple was approx. 21.5°C.
The test with the 46°C water was also good with a difference of maximum 0.3°C.
I also made the test with a glass of water at 79°C. The difference of temperature was in the range from 0.3°C to 0.4°C.
To sum up : The Thermoworks digital thermometer seems to work very well and is price competitive. I am in a hurry to try it while cooking sous vide!
Their is now a long time that I wanted to cook sous vide salmon with Turbigomme and a probe. Viktor Stampfer book indicates salmon should be cooked 54°C for 10 minutes (core temperature) with a 56°C water bath. In my former experiment I raised the time to 14 minutes, as I didn’t have any equipment to take the core temperature.
This time I purchased Turbigomme on a French site called svdiffusion.com. Turbigomme is a gum made to be glued on a pouch. The gum is supposed to be airtight if you go through with a probe. I bought it 8.85 euros (3 meters) + 10.94 euros shipping costs! I was really mad when I reallized that SVdiffusion cheated on shipping costs. Who can believe that a 110 gr parcel could be sent for 11 euros!
Anyway I have now everything: 4 cm Turbigomme piece, a 3 mm Mastrad probe (I know this is very thick but this is a cheap thermometer – less than 40 euros) , 2 rubbers to fix the Turbigomme in the case the self-adhesive would not be enough and a nice piece of salmon.
I glued the Turbigomme on the pouch, strapped it with rubbers and pierced the all with my 3 mm probe. I didn’t face any issue during this process. The pouch did not look like “loosing vacuum”.
During the cooking process I was doubting if air was not coming inside the pouch as I could see some bubbles appearing. I was feeling more comfortable when I saw the other salmon vacuum pouch I made without Turbigomme was doing the same…
To sum up I would say my experiment was successful. 8 euros Turbigomme (plus shipping costs!) and a cheap thermometer (40 euros max.) where enough compared to those very expensive 1 mm hypodermic thermocouples probes (approx. 200 euros) and thermometer.
My only issue was the cooking time. The starting temperature of the salmon was 8°C and it took 30 minutes to reach 54°C core temperature. My water bath was set at 56°C. I decided to take the salmon of the water bath as soon as the core temperature reached 54°C (instead of waiting 10 more minutes as suggested by Viktor Stampfer).
I was afraid the salmon would be overcooked. It was the case…nothing to do with a raw appearance salmon!
Next time I’ll try 72 hours pork ribs. No need of an internal probe for this kind of cooking!!!
While checking if a gas or a halogen stove could be used for sous vide cooking at low and constant temperature we used the Mastrad digital thermometer. I didn’t purchase Mastrad external probe to determine the core temperature of a product but to verify the temperature of the water contained in the pan only. For this specific purpose Mastrad probe was perfect except that I learned to one’s cost that Mastrad’s probe is not waterproof! I didn’t know that you should not immerge the probe above a specific point indicated on the picture below.
Then my thermometer became crazy and indicated a temperature 30°C higher than real. This dysfunction remained until I put the probe (including the metal cable) to soak in demineralized water for 30 minutes and dried the probe in the oven. Mastrad probe works perfectly again.
In order to complete my basic equipment for sous vide cooking at low and constant temperature I had to find a digital thermometer with an external probe. Here is my choice: a Mastrad thermometer that I purchased EUR 29 on internet. I was amazed to see how reactive the sensor was. You just have to put it in the water and you can see the temperature moving on the spot and reaching the correct temperature in 1 or 2 seconds. This precision will be necessary when measuring the temperature variation with the different techniques of sous vide cooking.