Rhubarb is the vegetable of my childhood, my mum was often preparing jam out of fresh rhubarb coming directly from our garden.
I found the post from The British Larder’s blog about rhubarb cooked sous vide interesting. Therefore I have decided to reproduce the recipe and try to obtain a delicious rhubarb tart.
Madalene recipe is easy:
- 140g rhubarb
- 30g sugar
- 30g water
- 1 vanilla pod
Madalena recommends a hard vacuum for this recipe. I was happy to test my MiniVac (a very compact vacuum chamber sealer) at this occasion. I am almost sure you can obtain a similar final result with a good clamp vacuum sealer.
With a storng vacuum, color of fruits and vegetables appear more intense as usual. It is also amazing to observe the sudden transparency of the food stuff.
Contrary to what was recommended by The British Larder (61°C during 20 minutes) I cooked the rhubarb 61°C during 45 minutes with my immersion circulator. I had the strange intuition that rhubarb can’t be cooked at 61°C during 20 minutes.
The result was excellent, not too soft, not too hard. The vanilla syrup was very tasty. The texture of the rhubarb was also surprising. As you will see on the picture bellow the rhubarb cooked sous vide at 61°C is not becoming mushy at all. The rhubarb remains in one piece.
Here is the final result, a rhubarb tart I let probably a little bit too long in the oven. Anyway, it was delicious.
I am currently using a clamp machine to vacuum my food stuff to be cooked sous vide. I decided one year ago to purchase a LAVA V100 which is in my opinion the best choice to start with cooking sous vide. I am still very happy with this machine but it is impossible to experiment compression with watermelon for example or to vacuum marinade or liquid in general. You can always freeze liquids or play with gravity as Casqu8 did in one of his posts but having a vacuum chamber machine is a must!
The problem is the price of vacuum chamber machines. Usually these vacuum machines can be purchased at price ranges from € 1,700 to more than € 4,000!! The size and the weight of a vacuum chamber is also an obstacle for individuals to have this kind of equipment at home. The weight is usually in the range from 50 to 120 Kg!
What is therefore the point of this post? Definitely a vacuum chamber machine can’t be integrated in your home kitchen except if you are a millionaire and your kitchen has the size of my flat.
The answer is the miniVac of VacStar a mini vacuum chamber directly coming from Switzerland. The miniVac is extremely small compared to his brothers and sisters 26 cm large, 40 cm long and 25 cm high. It weights 17 kilos.
Addélice which is the manufacturer of an immersion circulator called Swid also distributes the miniVac as a Pro sous vide kit. An immersion circulator and a vacuum chamber for less than € 1700, this is a lot of money but so far I haven’t seen any other cheaper high tech option.
I am chasing Addélice for months to test the miniVac and finally they have accepted to borrow it to me for the next 3 weeks. I received it yesterday and couldn’t wait to share my first impressions with you!
First impression is about the size. I knew it was small but I didn’t realize the miniVac was so compact before I saw it in real. It is small but so heavy! Take care to have a table that can resist to a weight of 17 Kg.
The size of the chamber seems also small 220 x 280 x 90 mm. In any case the maximum width of bags to be used is 20 cm. It is probably ok for most of my applications but probably too small if I decide to make a one piece beef filet for 5 people.
The parcel contains very few things, the miniVac, the electrical cable, some oil, an “L” frame key, a manual (2 pages!?), a liquid insert and a white plate (see the picture above).
The manual is limited to the minimum and is, in my opinion, not well made. There is such a discrepancy between the good feeling you have of the vacuum machine and the manual! I recommend to VacStar changing this ASAP.
In order to get an idea of the size of the Addélice sous vide Pro kit you’ll find a picture below with a 1.5 liter bottle of coke.
Starting with the minivac
First thing you have to do is to unscrew a cap in order to pour the oil provided with the miniVac (see on the pic below).
Then pour oil in the tube. The manual indicates you should absolutely let a “bubble of air” that should be visible on the screen on the back plate of the miniVac (see the picture bellow).
Features on the front panel
The miniVac has limited features available on the front panel.
The “on/off” button.
With the “Temp” button you set the time used to seal the pouch. The thicker the pouch is, the longer you need the seal it.
The “Vacuum” button sets the “time” to vacuum. In other words 10 seconds should be the maximum time needed to obtain a 99.8% vacuum.
The “Stop” button stops the vacuum process and seals the pouch at any time you decide to push it.
Lets try the miniVac!
For my first test I tried to vaccum seal water, just water. For this test the liquid insert is needed.
This new toy is opening a wide range of things to experiment during the next weeks. I am so exited!
Today I wanted to experiment confit duck legs. The idea came to my mind while reading Casqu8′s blog who cooked some weeks ago a couple of confit duck legs.
I copied Casqu8 recipe consisting in curing the meat with salt, thyme and bay leaf. I vaccum sealed the pouch and stored it in the fridge for 24 hours.
I rinced the legs with clear water and took care taking off the thyme and bay leaves. No need to leave them in the pouch, otherwise the final flavour of these aromats will be too strong!
Then I vaccumed sealed the duck leg with some duck fat (3 tablespoons) I purchased in a supermark (300 gr cost EUR 4).
In my first try I cooked sous vide the duck leg at 80°C during 9 hours with my immersion circulator.
I have not be satisfied with the final result. The confit duck legs were to dry in my opinion. Casque8 recommended me setting my immersion circulator at 75°C instead of 80, raising the cooking time to 20 hours and adding more duck fat (I have added 150 g per leg). The result was much better and I liked that confit duck leg very much.
I also tried 75°C during 24 hours with the same amount of duck fat. I had the feeling the additional 4 hours have not improved the texture of the meat. In my opinion the 20 hours duck legs cooked sous vide were far better.
Don’t forget to sear the legs both sides in a hot pan in order to obtain a crispy appearance, 20 to 30 secondes are enough.
There is now some weeks I wanted to verify by myself if a sous vide equipment is more energy efficient than a “traditional” convection oven. Cooking sous vide some kind of meats can take even several days (for example 72 hours pork ribbs at 57°C). What are the electricity costs?
How to proceed to illustrate this point?
My first thought was to compare the quantity of energy used by a convection oven and an immersion circulator (or a PID controller) in order to obtain the same doneness (rosé) on a 1 Kg beef filet.
Therefore I purchased in a do it yourself shop a very cheap appliance (EUR 11) to calculate the quantity of energy used by an electrical appliance (“consomètre” – refer to the picture on the left).
Unfortunately this “consomètre” cannot be plugged to my convection oven (the electrical cables of the oven are directly connected in the wall. In other word I have no mains where to plug this “consomètre”.
Thus I have decided to restrict my test to the assessment of the amount of energy used during a cooking process of at least 8 hours at 60°C. The final goal is to determine the cost of such cooking process.
I will not spend any time on the scientific explanation between Power and Energy since the purpose of this blog is only cooking. Nevertheless, for those who want to refresh their mind about physics basics I recommend reading this small article.
In order to determine the price of the energy consumption of an immersion circulator during 8 hours at 60°C I took a round pot of 15 liters and filled it with 28°C tap water.
It took 22 minutes for the swid to reach the target temperature of 60°C at full power (2,170 W).
Then the swid was stable very fast (some secondes only). At this stage the total energy consumption was 0.74 KWh which represents 8 cents (in France, 1 KWh = 0.11 €).
During the next 8 minutes the swid was struggling with power variation in the range from 50W to 600W. I would say the average could be in the area of 300W.
After 1 hour (excl. pre heating) the power variation was in the range from 14W to 200 W. At this stage (1:20 hours incl pre heating) the total energy consumption was 1.06 KWh.
Then I covered the tank with a plastic wrap in order to avoid water evaporation and let the swid run for additional 7:25 hours. When I came back in the morning the result was amazing. Power variation was in the range from 11 to 25 W. Total energy consumption was 2.05KWh (8:45 hours incl pre heating).
For France this represents a cost of approx. € 0.22 (0.33$ with currency rate of 1€ = 1.5 $). Astonishing isn’t it?
I received several questions of people interested by the swid of addelice. Their main worry was to determine if the swid is for professional purposes or for home cooks. To all of them I replied and said that I am not a professional and therefore don’t know their expectations as a professional. I realized that I tried the swid in 3.5 litres and 8.5 litres pots only. The manual of the swid indicates that the stability of the temperature is optimized up to 20 litres.
I went inside my uncle cellar and found an Ikea plastic box (€ 3) that I filled with 20 litres water.
I had to face a problem with the plastic container which is very flexible. Attaching the swid with the clamp to the container was not possible as the swid was too heavy. Therefore I found a glass cutting board that was perfectly the hight of the container. I put this board between the plastic container and the clamp. This generated an excellent stability for the swid to be attached.
I set the swid at 55°C only because I am not realy trusting in the Ikea container that could melt or not resit to higher temperatures. The manual of the swid indicates the Adaptive PID controller (that assesses the amount of the water i n the pot) was optimized if the starting temperature is at least 15°C lower than the target temperature. It took 15 minutes to heat the water from 25°C to 55°C and, after 5 more minute,s the stability of the water bath was excellent.
I decided to make an addition test: immersing a bottle of cold water (3°C) simulating a cold pouch in a water bath.
It worked perfectly.
To sum up I confirm the swid thermal circulator can heat easily a 20 litres water bath.