water), and, when the emulsion is re-formed , whip it while cooling!
Water! Cooks use it to wash and rinse things, to add some “liquid” when soaking something , to make
an infusion (tea, for example), or a decoction (stock!): it is the basis of soups, consommes, sauces…
and it is so common that it seems that there is nothing new to discover about it.
Just think of the difference in taste between melted ice and natural water. So called “ions” that are
dissolved in water in tiny quantity change its taste considerably.
But there are also culinary questions: for example, when you prepare an apricot glaze on a cake (a
shiny layer made by heating apricot jam with water, which is spread on top of the cake), the jam either
can, or cannot, solidify, depending on the calcium content of the water used in the preparation.
The same is true when you cook lentils, as shown in the next experiment:
Take three saucepans and put about 1 L of tap water into each of them. Then add about 200 mL
(about one glass) of vinegar to pan number 2, one spoon of sodium hydrocarbonate (this is the real
chemical name of bicarbonate of soda, of baking soda) to pan number 3, and nothing to pan number1.
To all pans, add 100 g of lentils (taken from the same bag) and bring to the boil for about 10 min.
Check the lentils in pan 1. When they are cooked, stop heating the pans, and compare the lentils: the
lentils in pan number 2 are very hard, while the lentils in pan number 3 have formed a puree.
Want to understand why?
II - 8 (of 9)
“Gelling agents”: this is something that promotes the formation of a gel.
What exactly is a gel? A gel is simply a solid full of water. But not like a box, imagine instead a room
filled with spiders that have spun webs in all directions. Flies would not be able to fly around, and they
would be trapped.
This is the case for water molecules (or the “flies”) in a gelatine gel: in this case, the gelatine
(remember, this is made of proteins from the connective tissue from meat or fish) acts as the spider’s