All About Wheat Flour

Questions and Flour Problems : Varieties and Classes


1.What is a variety?
A wheat variety is characterized by specific attributes such as resistance to weather conditions, enzymatic activity or growth height. Other objectives in breeding a variety are its protein content and the properties of the gluten. Varieties are usually approved and then checked again and again through monitored cultivation.

2. How is a wheat class defined?
A wheat class comprises all those wheat varieties complying with the definition for the class, e.g. colour, hardness, protein etc. The names of the classes and their definitions are characteristic of each wheat growing nation. But even similar names (e.g. Hard Red Winter) do not necessarily mean that identical quality parameters are used for classification.

3. Do the attributes of varieties vary?
The attributes of varieties should establish themselves in the growing areas, but that is not always the case. Weather conditions, especially, can cause the dominance of various attributes of the variety to be lost. “Replanting” of the wheat grains, i.e. sowing grains already harvested, can also result in loss of the desired attributes, so only new seed should be used.

4. How are consistent attributes of a variety achieved by breeding?
For decades plant breeders have ensured the attributes of varieties by crossing different wheat varieties and practising careful selection over a period of many years. More recently biotechnological methods have been used, including the transfer of genes, in order to achieve successful breeding more quickly. These methods will make it possible, for the first time, to introduce attributes from other organisms into the wheat to optimize characteristics such as weather resistance or water requirements. Genetic engineering enables the goals of breeding to be achieved faster.

5. What are the goals of breeding up to the year 2010 in D, EU, USA, Canada, Russian /CIS, Argentina, China?
In all countries breeding is ultimately directed towards increasing yield with less work. One possibility is to make the wheat plant resistant to pesticides, especially weed killers. Another goal of breeding may be to increase resistance to fungal attack. In view of climate changes the ability to thrive on dryer soils might be a further desirable characteristics. 
Whereas plant breeders used to operate in the regional level, they are now major international groups that produce seed throughout the world and market it for specific regions.

6. Which are the most common U.S. wheat classes for export?
HRW, HRS (including DNS), and HWW mostly for bread flour; SW and SRW are usually for cake and pastry flour and durum for pasta semolina.

7. We are currently using DNS/ CWRS wheat which is no longer available or is too expensive at the moment. Which variety comes closest to it?
Generally speaking, the balanced protein properties of these wheat varieties have to be achieved by mixing other wheats. In many cases it will be  necessary to combine a wheat with very firm gluten with a softer wheat. There are doubtless many examples of this. One would be a mixture of about 30% German Elite wheat with 60-70% A wheat and possibly a small amount of B wheat; other possibilities would be 40-50 % Australian Prime Hard mixed with Australian Soft, or Australian soft and Australian Hard in Suitable proportions.
Although it will not be possible to make such changes unnoticed in most cases, the miller’s customers will usually be able to achieve optimum baking properties after a short time, once they have got used to the new flour.

8. Can I replace 100% of the DNS wheat used in a bread flour if I apply the correct treatment?
Yes, if the target is to replace untreated or suboptimally treated DNS with a cheaper wheat. But optimally treated DNS is hard to beat in most bread applications as far as volume yield and dough tolerance are concerned. Of course some wheat varieties, e.g. CWRS, perform at least as well as DNS, though they are probably not cheaper.

9. Which is the main U.S. wheat class?
Hard Red Winter accounted for 41.5% (27 mio t) of the total production from 1990 – 1999.

10. How are wheat classes distinguished from each other?
Gene sequencing is the most accurate method of determining and distinguishing between wheat varieties. Determination of the migration of the proteins from a wheat in a gel by electrophoresis is also very precise. The visual and physical properties of a wheat can also be used to distinguish between wheat varieties, but errors are more likely to occur due to the multifactorial nature of the phenotype.

11. Are there methods for quick determination of wheat varieties?
For Canadian wheat, a sophisticated system based on the visual differences is being used to determine wheat varieties (KVD, kernel visual distinguishability). But it is very likely that this system will be replaced by a more reliable DNA fingerprinting system which  can be automated, in contrast to KVD.

12. Can Argentine wheat replace HRW of CWRS wheat?
Yes-occasionally. Unfortunately there is still no wheat classification system, so the fluctuations from batch to batch and from year to year are quite large. That makes it difficult to identify a wheat class that can certainly compete with high quality North American wheat classes.

13. Can the quality of French wheat be compared to that of Australian or North American Wheat?
Yes, it can. But the wheat is quite different. The quality of wheat from all for origins is usually very high; problems only occur when the wheat supplier changes. In most cases the milling and baking processes have to be adapted to the new wheat quality. After adaptation, similarly good results should be possible. Nevertheless, certain applications have been tailored to the wheat, so it will be difficult to produce a French baguette with all its inner and outer characteristics with Australian or American Wheat, or to obtain a pan bread with extremely low specific weight such as American toast bread from French Wheat.