Молекулярная гастрономия для креативных шеф-поваров (англ. язык) - страница 149

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

wavelengths of light. The red fruits will take on an attractive red-orange colour.

Why not use galvanised copper (the copper is covered with a tin layer? The tin will prevent the copper

from being removed from the bottom of the pan, so it will not be able to play its roles in favouring

pectin extraction and keeping the bright red colour. The tin ions that are released will instead bind to

the pigments, changing their configuration and therefore absorption spectrum, and thus giving the jam

an unattractive purplish colour.

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More about culinary ingredients: Flour

Flour production

Ordinary flour is produced from crushing up the grains of a wheat plant.

To prepare flour, the outer layer of the wheat grain is removed. Although this layer is edible, it contains

lipids which reduce the shelf-life of the flour. The grain is then ground to produce flour.

Flour composition

Flour is mainly composed of starch molecules – the amylose and amylopectin molecules, which are

organised together into starch granules. These starch granules contain circular layers of amylopectin

and amylose molecules held together by hydrogen bonding.The starch content of flour constitutes

between 70 to 80% of flour weight.

Flour also contains proteins (approximately 10% of the flour weight). Flour contains many different

types of proteins – the majority of these proteins are insoluble in water (the gliadines and the

glutenins), the rest are soluble in water (the albumines and globulins). It is the insoluble proteins that

have an important role in the food preparation – they form coagulated networks that are responsible

for holding the shape of flour based foods such as bread, pasta and gnocchi.

The composition of flour can be demonstrated by simply adding flour to water. Some of the flour will

form a soft sticky dough with the water, whereas the rest of the flour will be washed into the water,

which will become cloudy. The part of the flour that is washed into the solution include some of the

starch granules (which make the solution cloudy) as well as the remaining flour components (soluble

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