Молекулярная гастрономия для креативных шеф-поваров (англ. язык) - страница 18

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

(strong electrostatic forces), and between hydrophobic groups (slightly weaker hydrophobic

interactions).

Some forces are also involved in stabilising intramolecular loops.

The hydrophilic groups on the outside of these proteins, because they are charged, help individual

protein bundles to stay separate from each other. Raw protein sources are thus often transparent

because the gaps between individual protein bundles allows light to pass through. This gives raw egg

whites and meat and fish flesh their transparency.

-------- proteins

-------- inner protein bonds

Hydrophilic group Hydrophobic group

In their highly folded form, proteins trap a considerable amount of water molecules within their highly

folded structures. As these proteins start to denature, some water is actually freed from between the

proteins and this causes an initial increase in “free water”, which in food tends to be perceived as

juciness.

Protein modifications

Denaturation

The weak bonds that hold the protein 3-dimensional structure together can be fairly easily broken – by

the addition of heat, acid, salt or mechanical force (e.g. mixing). As these bonds holding the proteins

structure together break, the protein unfolds into its long chain, exposing all its previously protected

amino acids. This process is called denaturation. Our stomachs more easily digest denatured proteins,

so proteins are often expressly denatured (either by cooking with ...

cess is called denaturation. Our stomachs more easily digest denatured proteins,

so proteins are often expressly denatured (either by cooking with heat, curing with salt, or pickling with

acid) before they are consumed. Heat is quicker to denature proteins than acid, salt or mechanical

force, which is why cooking meat is a much quicker process than curing or marinating meat.

IV/II - 3 (of 6)

Uses of denaturation:

Denatured proteins have many useful functions in cooking. Not only are denatured proteins much

more digestible than raw proteins (the groups are more accessible to digestion by enzymes), they are

also useful in food preparations. Their use in such food preparations tends to be based on the

principle that in denatured proteins, unlike in raw proteins, both the hydrophobic and the hydrophilic

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