Flour is a powder which is made by grinding cereal grains, beans, or other seeds or roots. It is the main ingredient of bread which is a staple food for many cultures.
Wheat is the grain most commonly used to make flour. Certain varieties may be referred to as “clean” or “white”. Other terms are given to wheat flour depending on its gluten content. Products with a high amount of gluten are identified with terms such as “strong”, or “hard”, whereas those with low levels of the protein are referred to as “soft” or “weak”. “Brown” and wholemeal flours may be made of hard or soft wheat.
Flour contains a high proportion of starches, which are a subset of complex carbohydrates, also known as polysaccharides. The kinds of flour used in cooking include all-purpose flour (known as plain), self-rising flour (known as self-raising), and cake flour including bleached flour. The higher the protein content the harder and stronger the flour, and the more it will produce crusty or chewy breads. The lower the protein the softer the flour, which is better for cakes, cookies, and pie crusts.
The production of uniform bakery products require control over the
raw materials used in their formation. Flour is a biological material
and when obtained from different sources can vary considerably in its
protein quality, protein quantity, ash, moisture, enzymatic activity,
color, and physical properties. It is essential to be aware of any
variations in these characteristics from one flour shipment to the next.
The purpose of flour testing is to measure specific properties or
characteristics of a flour.
Wheat quality and methods in wheat quality determination is important. Determination of the quality of bakery products which have significant position in the food industry and nutrition is necessary from the point of product features and economic view.
However, the choosing of appropriate raw material according to that appropriate quality of wheat/flour/semolina is very important to produce products such as bread, biscuit etc. Beside that, methods and analysis which are used to determine the quality must be applied exactly and results must be well evaluated by the aid of good qualified technical personelle and equipment. Nowadays the importance of technical personelle, equipment and methods for determination of quality is accepted by the consumers and producers.
Wheat is important, rather than other grain. Because;
1. It is raised in a large area and able to fit different climatic and earth conditions.
2. It has high yield and easy to grow.
3. It is easy to store and high nutrition value.
4. When wheat flour is in contact with water, protein particles in flour form gluten (wet germ).
No other grains protein, except wheat, form wet germ.
Wheat kernel contains several layers, germ, endosperm, aleuron layer, bran, outer kernel layer.
The germ and bran are removed from the kernel when white flour is milled, even though they contain nearly all the fiber and B vitamins; they are removed because they also negate the elastic properties of the gluten, which is so vital to the texture and crumb of the bread.
The percentage of total product in any desired fraction of flour is called extraction. In other words, straight grade flour that is 72% of the total product is 72% extraction flour. The composition of flour with various percent extractions is given in the table below.
Approximate Composition of flour.
Component Flour 72% Flour 80% Whole Meal 95% – 100% Wheat Germ Wheat Bran Moisture % 13 – 15 13 – 14.5 13 – 14 9 – 12 14 Protein % 8 – 13 8 – 14 10 – 15 25 – 30 12 – 16 Fat % 0.9 – 1.4 1 – 1.6 1.5 – 2.5 8.5 – 11 3 – 4 Carbohydrate % 65 – 70 64 – 70 60 – 68 39 – 45 —- Fibre % 0.1 – 0.3 0.2 – 0.4 1.8 – 2.5 2 – 2.5 9 – 12 Ash % 0.3 – 0.5 0.6 – 0.9 1.2 – 2.0 4 – 4.5 4 – 6
Wheat that is between the bread and pastry types are used for cracker, doughnut, and all purpose flour.
* Nutritional values are a guide and average values only. Values will vary dependent on genetics, environment, management systems, storage and climatic conditions.
As all feeding systems and requirements are different, it is recommended you seek the advice of a nutritionist to best develop a suitable feeding program for your requirements and feeding rations.