Wheat protein

What is wheat?

Wheat or wheat, whose Latin name is triticum, is a widely used cereal (therefore, a grass), because it can be adapted almost to any climate and soil on the planet. Thanks to its very high productivity, it is also possible to obtain food products at medium and low cost but characterized by a considerable energy supply.

The wheat is mainly used in the production of flour, from which it is possible to obtain various types of bread and pasta.

Wheat flour is obtained by grinding and sieving (sieve) of the grains, and depending on the refining of the flour it is possible to produce: wholemeal flour (the richest in fiber), type 2 flour, type 1, type 0 and type 00 ( the poorest in fibers).

Nutritional aspects

The grain contains all three macronutrients, but being a cereal, the relative energy supply derives above all from the glucidic portion in complex form (starch). The lipid quota is decidedly limited and, like the fiber, inversely proportional to the degree of refinement; the wheat is cholesterol-free and contains above all unsaturated fats (therefore of good quality) but - assuming a contribution comparable to that of the food portions recommended in the national guidelines - it does not have a decisive effect on the overall lipid balance.

Regarding the quantity and quality of the proteins contained in it, wheat is NOT one of the most valuable food protein sources; however, we recall that the dietary role of wheat in achieving the recommended ration of essential amino acids MUST be contextualized and subjectively evaluated.

Wheat also contains predominantly NOT soluble dietary fiber which is proportionally accompanied by Niacin (vitamin PP) and magnesium (Mg); the higher the level of refining and the lower the quantity of micronutrients and dietary fiber of the flour.

Wheat protein

Based on their solubility, wheat proteins can be classified into four groups:

Water soluble albumins
Soluble globulin in neutral saline solutions
Gliadins soluble in diluted alcohol
Glutenines soluble in diluted acids

Albumin and globulin are water-soluble proteins, while gliadins and glutenins represent the water-insoluble portion and associated form GLUTEN.

Among the wheat proteins, gluten is the one best known for:

Its essentiality in bread making
The high potential to create a widespread food intolerance: the CELIAC DISEASE

To date, the diagnosis of celiac disease seems to be on the rise, although many of these concern less serious or almost asymptomatic forms; moreover, such a diffusion is undoubtedly contributing to the onset of many other ATYPIC intolerances and probably of a psychogenic nature.

Wheat proteins are defined as having a low biological value (VB <55), and present a significant deficiency of lysine. Hence the need to associate them with other protein sources, as they are insufficient to fill - by themselves - the amino acid requirements of the body. This aspect assumes a significant importance for those who follow a vegan diet, where the absence of animal proteins requires a careful combination of the various vegetable protein sources in order to fill the relative protein deficit.
Excellent content of glutamic acid and proline.

Protein source	Required protein supplement (g) *
Beef	1.0
Cow milk	1.6
eggs	2.6
Soy	6.2

The water-soluble protein portion (albumins and globulins) accounts for 20-35% of the total, while gliadins (about 20 types of monomer proteins) represent a further 30-40% of the total and differ on the basis of mobility in: α and β (45-60% of total gliadins), α (30-45% of total gliadins) and β ‰ gliadins.

Glutenins represent 40-50% of the wheat protein complex and are divided according to molecular weight; those with low molecular weight are about 60-80% of total glutenins.

Wheat Protein Supplements in Powder

In the form of a food supplement, powdered wheat proteins are marketed by commercializing the absence of lactose and cholesterol, the high intake of glutamine and suitability for consumption by vegans.

By way of illustration only, we report the amino acid composition of various protein supplements, so as to obtain an immediate comparison between the wheat proteins and those of soy, whey and egg; it should be noted that the sum of the individual amino acids does not coincide perfectly with the total protein content (due to technical flaws that can be found in practically all the cards of the producers).

Amino acid profile	WHEAT PROTEIN*	SOYA PROTEIN *	MILK SERUM PROTEINS ^	MILK SERUM PROTEINS °	EGG PROTEINS *
Amino acid profile	g / 100 g	g / 100 g	g / 100 g	g / 100 g	g / 100 g
Protein	83.3	90	80	90.5	76
Aspartic acid	2.92	10, 35	8.8	10.1	6.67
Glutamic acid	26, 92	17, 28	14.5	14.2	8.71
Alanine	2.21	3.87	4.0	4.6	3.79
Arginine	2.58	6.75	1.7	2.4	3.57
Cysteine	2.31	1.08	1.8	3.2	1.69
Phenylalanine	4.63	4.68	2.4	3.1	3.83
Glycine	3.37	3.69	3.4	1.5	2.30
isoleucine	2.88	4.32	5.1	5.1	3.71
Histidine	1.66	2.43	1.4	1.6	1.48
Leucine	6.26	7.2	8.5	11.5	5.53
Lysine	1, 425	5.67	7.7	9.0	4.47
Methionine	1, 150	1.26	1.6	1.9	2.26
Proline	11, 33	4.68	4.4	3.6	2.5
Serina	4.28	4.95	3.7	3.6	4.52
Tyrosine	2.62	3.42	2.1	3.4	2.55
threonine	2.11	3.33	5.4	4.3	2.99
Tryptophan	1.6	0.99	1.1	1.9	0.80
Valine	3, 092	4.32	4.7	4.5	4.17

Gluten

Gluten is a lipoprotein formed by gliadin and glutenin in the presence of WATER; these components are NOT present only in wheat, but also in other cereals. Among them the most common are: spelled, rye, kamut and barley.

Gluten is composed of 75-85% protein, 5-7% lipid, 5-10% starch and only 5-8% water; gluten is activated ONLY in the presence of water, therefore it is possible to isolate it from the flour by simply hydrating it and subjecting it to multiple consecutive washes to progressively dilute the residual starch. A similar procedure can be useful for the evaluation of the "strength" of this protein (useful in bread making) or for the preparation of seitan, a dietary-vegetarian substitute for meat. Gluten is also used as a thickening and industrially additive as a glue for the dressing of paper and fabrics. In culinary preparations, gluten provides above all ELASTICITY thanks to the typical NET structure (which holds carbon dioxide) and allows the dough to rise.

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