Wheat

Common wheat and Durum wheat

The different characteristics between the two great families of wheat are due to the specifications of the kernel in milling and the destination use:

The kernel of common wheat has a fracture surface powdery, white and opaque by milling and sifting process to produce flour.
The kernel of durum wheat has a fracture surface vitreous, translucent and transparent, from the milling and sifting are obtained semolina

In Italy there are many cultivated varieties, certainly a heritage of quality and value, but the only deficiency are variety in particular with low and poor quality of gluten. This implies the need to import high quality varieties to complement our national product (in particular US and Canadian varieties) especially for common wheat.

The grain composition

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83% endosperm intended to milling to obtain flour (Common wheat) semolina (Durum wheat)
15% casing from which we get the bran
2% embryo to a lesser measure falls to be part of the flour

The endosperm composition

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79% starch
14% protein
2,3% fibre
2,3% fat
2% ashes

The average starch content of the Durum wheat is higher than that of the Common wheat.

Grain quality

The quality must be understood in reference to the different applications of flour: bread, pasta, biscuits, cakes.

Common wheat

Important parameters for assessing the quality of the grain:

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varietal uniformity
moisture (affects conservation and made into flour)
ash content of flour (essentially dependent on the percentage of endosperm of the kernel and the average weight for the kernel)
protein content (influence, together with the gluten content, although not exclusively, the bakery and pasta product)
quality and quantity of gluten (directly influence the quality of the product, while the quality of the gluten present depends on two physical characteristics of gluten same tenacity and elasticity, that contribute to the technological abilities of the product.)

The quality and the technology abilities of wheat are evaluated by laboratory tests that provide indices of the quality of the product.

The most significant indices are:

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moisture in the kernel
ash content
alveografica analysis
evidence of bread making
content of nitrogenous substances

The alveografica analysis in particular allows to derive two important indices:

P / L ratio of tenacity and elasticity (optimal value between 0.4-0.6 over 0.6 we will have a hard bread, compact and of little mixing development, while under 0.4 a sticky dough and soft.)
W index extensibility of the dough that allows the collocation of the wheat according to the products derived from them.

W index:

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