In the past couple of weeks my
post-olympics / pre-paralympics TV void has been nicely filled by the return of
Great British Bake Off and Celebrity MasterChef. The kitchen skills employed by
the celebrities currently embroiled within the latest series of MC have yet to
reach the level of molecular gastronomy but if like me you are a regular viewer
of anything that features Gregg Wallace, Michel Roux Jnr or Heston Blumenthal I’m
sure you will be familiar with the concepts of making ice cream with liquid
nitrogen or the creation of foams with CO2 loaded canisters.
Another technique that seems to
have been adopted on TV cookery programmes in the last few years is sous vide
cookery. If you don’t know what sous vide cookery is it basically involves
cooking food in sealed plastic bags which are placed in a water bath at a
specifically set temperature, which allows the food to be cooked for long
periods of time without overheating and overcooking. By cooking for a longer
period of time at a lower temperature than in an oven or under a grill the core
of the food reaches the desired temperature without overcooking the outside and
this is meant to help food retain its juices and flavours. Since the rise in
popularity of this cooking method (despite it being first described in 1799 by
Sir Benjamin Thompson…so Wikipedia informs me!!!) sous-vide machines for the
domestic kitchen are now available but with a price tag in excess of £200 they
probably aren’t classed as an essential kitchen gadget by the majority of
people no matter how foodie obsessed they may be!
There are however numerous
examples on-line of DIY versions of sous-vide cookery, often involving cool
boxes or slow cookers. And so I was inspired to embark on the world of
sous-vide cookery without the aid of fancy gadgets or machines but simply a
slow cooker, some sandwich bags and a digital thermometer!
I think the obvious choice for
sous vide cookery is steak and so after a quick trip to my local butchers I
returned with a couple of sirloin steaks all ready to go!
EQUIPMENT
Slow cooker
Digital kitchen thermometer
Large sealable sandwich bags
METHOD
Begin by choosing the temperature
at wish you would like to cook your steak, which will of course depend on how
you like to eat steak! The following table should give an indication of the
temperature you should be aiming at;
Rare
|
52-55°C
|
125-130°F
|
Medium-rare
|
55-60°C
|
130-140°F
|
Medium
|
60-65°C
|
140-150°F
|
Medium-well done
|
65-69°C
|
150-155°F
|
Now you need to fill the slow
cooker with water at the appropriate temperature. I did this by boiling a
kettle and half filling the slow cooker with the hot water before adding cold
water to achieve the desired temperature using the digital thermometer. Then I
set the slow cooker to the ‘Warm’ setting to try and maintain the temperature
of the water.
I found that during the cooking
process the water temperature in the slow cooker did slowly creep up so I began
by setting the temperature of the water at the lower end of the temperature
range I required (e.g. for a medium-rare steak begin by getting the water to 55°C).
Next place the steak into a
sandwich bag. I cooked 2 steaks at once in my slow cooker but placed each in a separate
bag. To expel all of the excess air from the bag take a large bowl filled with
cold water and slowly lower the sandwich bag containing the steak into the
water until the opening of the bag is just above the water level. This should
force the air out of the bag so that the bag can then be sealed up.
Then take the sealed up steak and
lower into the slow cooker before placing the temperature probe part of the
thermometer into the water and placing on the lid and leaving to cook for 2
hours.
As I explained I did find that
the temperature of the water slowly crept up over the cooking period and didn’t
remain constant as it would do in a real sous vide machine. So I kept checking
the thermometer reading throughout the cooking process and as it began to near
the upper limit of the medium-rare cooking range (60°C) I would add a little more
cold water to reduce the temperature back down to 55°C. Handily my digital thermometer
has an alarm that sounds when the desired temperature is reached so I was
quickly alerted to an undesired rise in temperature and was able to adjust the
water temperature when needed.
But apart from the odd addition
of a cup of cold water you do just leave the steak cooking away for a couple of
hours which left me with plenty of time to get on with preparing the all
important accompaniment of chunky chips!!!
After 2 hours turn off the slow
cooker and remove the steak containing sandwich bags. Take a large frying pan
and place over an incredibly high heat and leave until the surface of the pan
is volcanically hot. Then remove the steaks from the sandwich bags and place in
the pan searing the steaks on each side to produce a nice brown and caramelised
finish. This last cooking stage should really only take a matter of seconds on
each side and just provides a little extra colour as the steaks are perfectly
cooked on removal from the makeshift water bath.
And there you are…a sous vide
style steak ready to serve up alongside those chunky chips and perhaps a good
dollop of English mustard!!