Posts Tagged ‘fish’

TFP 2011: Sous vide master class (part 2)

Friday, April 1st, 2011


Sous vide fish should be cooked at several temperatures followed by stepwise cooling for the best texture

Bruno Goussault started the sous vide master class at The Flemish Primitives 2011 by arguing that precise temperature or right temperature cooking is a better term than low temperature cooking. It’s really about knowing at which temperature the desired change takes place (or even better: knowing which time-temperature combinations will yield the desired results – this is a topic I will come back to soon).

Recounting the early days of sous vide, Bruno Goussault explained how he was once asked about how to produce prepare tender meat from a though cut. He was aware of a science paper on a slow cooking technique from USA (anyone know which paper this was?). It utilized a water bath, but the water washed away the juices. To avoid this Bruno wrapped the meat in cling film. A roast beef cooked at 58 °C turned out tender with a nice pink color. Then a friend working with plastics suggested that he should look into polyethylene (PE) bags in combination with a sous vide machine (boil-in-bag had already been around for some time apparently). Interestingly Bruno mentioned that during a recent Bocuse d’Or competition in USA where Bruno trained the American team, they replaced the plastic with a “skin” made from shrimps. Maybe we will see more “edible” skins used in sous vide in the future?

VACUUMING
Bruno then went on to talk about the vacuuming process and how time/pressure profiles should be adjusted (more…)

TGRWT #15: Smoked salmon in cocoa gel with lime

Sunday, March 1st, 2009

The TGRWT #15 challenge was to pair smoked salmon with dark chocolate. I decided to encase a piece of hot-smoked salmon in a cocoa gel and serve it with sugared slices of lime. But as you can see from the pictures quite a lot went wrong… But it tasted quite nice!
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Simple temperature calculations

Thursday, March 8th, 2007

Although I recommend the use of a thermometer, sometimes it’s convenient to know how you can also manage without. If you mix water at two different (but known) temperatures, you can easily calculate the temperature after mixing. Just multiply the temperature of each part with the relative amount. For example, if you have 3 dL at 100 °C and 7 dL at 10 °C (which happens to be the approximate temperature of my tap water), this gives (3 dL x 100 °C + 7 dL x 10 °C) / 10 dL = 37 °C which is just perfect for dissolving fresh yeast when making bread.

You can also do it the other way around. Let’s say you have boiling water and you know that your tap water is approximately 10 °C. If you want water at approximately 37 °C, you can do as follows:

temperature-calculation.jpg

Start by writing what you have to the left (100 °C and 10 °C) and what you want in the middle (37 °C). Subtract: (100-37) = 63 and (37-10) = 27. And voilá – you need 27 parts water at 100 °C and 63 parts at 10 °C (and 27:63 simplifies to 3:7 which is what we found above). Now of course if you really wanted water at 37 °C, you would simply put your finger in to see if it’s at body temperature…

Are there any practical applications of this? Yes – a simple, but elegant way to prepare fish would be to drop a fish of known weight and temperature (fridge @ 4 °C or freezer @ -18 °C) into water that has been brought to boil. Cover pot and turn off heat. The amount of water would be calculated based on the desired temperature of the fish. We are assuming here that there is no heat loss to the surroundings, which of course isn’t quite true. How fast pot of water will cool depends on how much water you use and on the pot. This can be corrected for, and luckily someone has already done it. More on this in my post on how to cook fish in cooling water.

We can apply the temperature calculation from above to figure out roughly what the temperature will with this cooking method. 800 g of fish from the fridge (4 °C) and 2,4 L of boiling water gives a temperature of (0,8 x 4 °C + 2,4 x 100 °C) / 3,2 = 76 °C. The cooling curves for a pot with 2,5 L of water suggest a temperature loss of 15-20 °C in 30 min which would bring us down to 55-60 °C which – considering that no thermometer is used – is quite good.

Cooking fish in cooling water

Thursday, March 8th, 2007

I have previously written about how you can cook a perfect steak with a simple DIY sous vide technique. Of course low temperature cooking applies equally well to fish with the only difference that the temperature can be turned down even lower.

A slightly different approach for cooking fish was presented by Haqvin Gyllensköld in the Swedish book “Koka, steka, blanda” from 1977, which I became aware of through Östen Dahlgren’s book “Laga mat – hur man gör och varför”. In stead of keeping the fish at a constant temperature (which requires quite some attention unless you have a thermostated waterbath), in this method, as the hot water cools, the temperature of the fish increases until they’re at the same temperature.

This is how you do it:

  1. Weigh the fish
  2. Boil the triple amount of water
  3. Add some salt to the water (15 g / L)
  4. Put the fish in the water and remove the pot from the stove
  5. Check the graph below for how long the fish should be left in the cooling water
  6. Serve!

cooking-fish-in-cooling-water.jpg

Need help on fish names in different languages? Yeah, me too!