centre of the meat except by diffusion, which is a very slow process (in a gelatine gel with 1% gelatine,
where diffusion is easier than in meat, because there is no collagenic tissue, diffusion takes place at a
speed of only 1 cm per day). In September 2004, the expression “cooking by concentration” was
dropped from the French culinary curriculum.
The other expression, “cooking by expansion”, was also dropped. This expression referred to boiling
meat, and it is strange that it survived for so long, as any cook can easily observe that meat is
shrinking when boiled.
Moreover experiments demonstrate how wrong this old theory is. It was written, even in recent
textbooks, that, when producing meat stock, meat should be put in cold water, “otherwise albumin
coagulation at the surface, in boiling water, would prevent juices from going from the meat to the
stock”. True or not?
First it should be emphasized that “albumin” is a very old (more than one century) word for what are
now called proteins. It is true that there are some albumins (serum albumin) in blood (and therefore in
meat), but meat cooking is not due to albumin coagulation: the proteins that coagulate are actin,
myosin and others. An easy experiment can be done to check the culinary theory: if it were true that
meat coagulation at the surface, in boiling water, prevents juices losses, then meat put in boiling water
should be heavier than meat in initially cold water. A balance is enough to check this.
Let’s divide a piece of meat into two equal parts, with the same amount of fat in both pieces, and let’s
cook one piece in boiling water, and the other one in initially cold water. Every ten minutes or so, let’s
take the two pieces, dry them rapidly and weigh them. The following curve is obtained:
201 0 203
0 100 200 300
Figure 9. The mass of two pieces of meat put either in initially cold or boiling temperature