|
Different grades of flours can be obtained by milling of wheat. The flour streams from the various rollers are named for the roller ‘first break stream’ etc. They vary in
chemical composition because of variation in the amount of bran, endosperm and germ they contain. Many different flour streams are produced in large mills. These streams are combined and blended to form flours with particular baking characteristics
Straight flour
It is combination of all flour streams. It is seldom produced. Composition of straight-run flour in terms of proportion, colour grades and protein from three streams are given below:
Parameter
|
Stream 1
|
Stream 2
|
Stream 3
|
Straight run
|
|
Total flour produced (%)
|
65.00
|
30.00
|
5.00
|
100.00
|
|
Colour grade
|
-0.50
|
4.00
|
10.50
|
1.40
|
|
Protein (per cent)
|
10.00
|
11.00
|
14.00
|
10.50
|
Patent flours
Patent flours are from the more refined streams and vary considerably in the percentage of the total flours represented. Characteristics of these flours are determined by percentage of separation. The manner in which the particles of endosperm are separated is called ‘separation’ where as extraction, refers to the percentage of flour which has been extracted from wheat kernel. Following approximate percentage of patent flours:
- First patent: 70 per cent of total flour, used for cakes
- Short patent: 80 per cent of total flour, used for breads.
- Medium patent (also called cut off flour): 90 per cent of total flour, used for breads.
- long or standard patent: 95 per cent of total flour
Clear flours
The flour remaining after the patent is removed is called clear flour and it may be separated in to different grades. It is also called low grade flour. This flour which comes from the tail end of the breaks and reduction system is dark in colour. Clear flours are strong and are suitable for rye and other dark breads. Clear flour has more good quality proteins. Flour made from soft wheat’s is used for cakes, pastries and biscuits. Hard wheat varieties are used for the production of yeast leavened breads. Amber durum wheat’s are used for the production of noodles, macaroni etc.
Red dog flours
Thelast reduction flour is called red dog. It is dark in colour and contains large amounts of bran and germ. It is usually sold as animal feed.
Wheat shorts
This is another fraction obtained in rolled milling of wheat. It is found mixed with bran and germ in the milled feed.
Germ
In the process of roller flour milling, germ is eliminated along with mill feeds. It can be separated and used for the production of wheat germ oil. The residual solvent extracted wheat germ is in proteins and B- vitamins and can be used in the preparation of weaning foods.
|
Participants