Молекулярная гастрономия для креативных шеф-поваров (англ. язык) - страница 140

Молекулярная гастрономия для креативных шеф-поваров (англ. язык)

the vegetable will lose water as if it is “wilting”. Care needs to be taken that the vegetables are not

overcooked – or they will become overly soft and undesirably mushy. Vegetables are sometimes

salted while cooking, to bring out their taste as the salt diffuses into them. However, the salt draws the

liquid out of the vegetables by osmosis, and this further softens the vegetables.

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Nutrient losses

Vegetables contain many nutrients and are an important source of vitamins in our diet – especially

vitamins A, B and C. Many of the nutrients are destroyed when the vegetable is cooked, either by

dissolving into the cooking water, or by being broken down or destroyed by the heat. Although vitamin

A and the molecules that form it are not water soluble, both vitamin B and C as well as the minerals

are, and will leak into the cooking liquid. Finely chopped vegetables are especially prone to losses of

vitamin C. Finely cut up vegetables expose a large surface area to the cooking water for vitamin C

loss, but additionally, because the vegetables have been finely chopped, sufficient amounts of an

enzyme that further contributes to the degradation of vitamin C. This enzyme is most active at high

temperatures, although it is degraded in boiling water, and so has a most pronounced effect as soon

as the vegetables to be boiled are added to the boiling water, since the water temperature temporarily

drops to below boiling.

The other nutrients that are most commonly lost include sugars and starch.

Nutrient losses increase with cooking time and volume of cooking liquid.

Prevention of the leaking of nutrients can therefore be helped by cooking vegetables in a small

amount of water, or else using the cooking water to make a sauce/soup etc

Changes to colour

Green vegetables:

Green vegetables are green because their cells contain large amounts of the pigments chlorophylls,

which are a large molecules containing a magnesium ion at its centre.

Green vegetables also contain other coloured pigments but in much smaller quantities.

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