Wheat protein. Nieqing Feiyan Yangjin Guiling. Key points. Amino acid in wheat protein Fractions of wheat protein Dough formation Tiny knowledge concerning wheat protein.
the mass of Amino acid in 1g of a test protein
the mass in the recommended pattern
In general, Lys is the first limiting AA
The –SH in Cys is replaced by the band
–S-S quickly that increases the plasticity、viscosity and elasticity of the pastry.
The high content of Glu makes pastry delicious
and acid- or alkali-soluble glutelins.
5% 10% 69% 16%
When mixing and kneading a mixture of wheat flour and water (about 3:1 ratio), several transformations occur.
The major reactions
—These agents promotes the formation of disulfide linkages
—These agents promotes the breakage of disulfide.
Gluten protein mixed with Ascorbic acid
some salad oil refrigerated under 2℃ for 3h dealed with warm water (90℃)for 2h
gluten protein clabber
-- Ascorbic acid acts like an oxidizing agent
Because it is rapidly converted to dehydroascorbic acid by ascorbic acid oxidase
The shear and tensile forces.
—Gluten proteins absorb water and partially unfold.
—The unfolding molecules facilitates hydrophobic interaction
Gluten, especially the gltutenins, are rich in proline, they have very little folded structure. Therefore, no additional unfolding occurs during baking.
In milling process , the nutritional components of the endosperm, such as native lipids high in glycolipids(糖脂) and other nutritional proteins are separated from the gluten proteins. Especially , it’s low in Lys and Thr.
The lack of the nutrition have become a limitation . This problem is requiring us to settle !
→fat molecules, air bubbles and ice
crystals assemble within a highly
concentrated mixture of sugar
→Priests in ancient Egypt used wheat to hallucinate,
and in bandages, to ease the pain of a wound.