Question and Flour Problems (Flour Components; Starch)


1.What is the percentage of starch in wheat flour?
Wholemeal flour contains 60% starch, and light-coloured flour with an extraction level of 75 to 80% contains about 70% starch. In both cases this is based on a moisture content of 14%.

2. What are the differences between the starch fractions?
Wheat starch consists of about 25% amylose and 75% amylopectin. The amylose is made up of glucose chains, i.e. of linked alpha-D-glucopyranosyl groups joined to the C1 and C4 atoms, with very few branching points at some C6 atoms. One amylose molecule contains about 200-2,000 glucose sub-units. Amylose molecules have the structure of left-handed single or double helices. Amylopectin is a much larger molecule (approx. 6,000-100,000 glucose sub-units) characterized by frequent branching at the C6 atom.

3. How are starch and damaged starch determined analytically?
The amount of starch in a wheat flour can easily be determined by washing the starch out and drying the suspension thus obtained. The determination of the damaged starch can be carried out by chemical end group analysis or modern enzymatic methods. In this case special enzymes are used that cause measurable conversion of materials.

4. What role does starch play in the dough, in the baking process and during storage of the baked products?
During preparation of the dough the starch attaches a large part of the water used in the process to its surface. Damaged starch can even bind water at temperatures below the gelatinization point. During baking the gelatinizing starch binds the water separated from the protein and adsorbs it. When the baked product cools down to a temperature below 60 0C the starch begins to age (retrogradation or syneresis). This process is very slow at first, but at temperatures between 15 oC and freezing point the starch ages much faster. This change in the starch makes the crumb of bread firmer, a process that can be reversed partially and for a short time by re-baking.

5. Do the carbohydrates of the wheat react with flour improvers and baking agents?
The activity of the endogenous starch-degrading enzymes is usually too slight for the production of wheat bread, so they have to be optimized with suitable enzymes e.g. a-amylase or xylanase from microbial sources. Malt flours are only of limited use, since they also contain protein-degrading enzymes that soften the gluten.

6. What are the processes that cause staling?
Re-crystallization of starch, particularly amylopectin, and moisture migration from the crumb into the crust are the major causes of staling in bread.

7. Does the quality of the starch (not just damaged starch) in our flour affect the quality of the bread in addition to the usual parameters measured?
For many years we have been observing a fluctuating response of the starch to rheological tests such as the amylograph. Although one and the same wheat variety may have similar Falling Numbers and even similar maximum viscosity figures in consecutive years, the gelatinization temperature may vary considerably. So far it can only be speculated that the protein-starch-pentosan matrix of the starch granules differs. In years with less moisture it is likely to be denser, so gelatinization occurs at higher temperatures. In the bread, this will be perceived as a lack of crumb softness or reduced duration of the crumb softness. Malt flour, amylolytic and also xylanolytic enzymes help to improve the situation.


Questions and Flour Problems : Milling and Extraction


1.Is the world milling industry growing?
The capacity of the milling industry is slowly growing. This growths appears to be mostly due to the growth of the world population. Only in a few regions, particularly in Asia, the consumption of wheat flour is also growing. In contrast, the number of mills is decreasing due to mergers and increasing capacities of new mills.
2. Does the particle size of the flour influence the effect of the enzymes?
The finer the particle size, the larger is the area that can be attacked by the enzymes. Moreover, the constituents of the flour hydrate faster, and this makes them more readily accessible to the enzymes, because a fine particle size is often accompanied by greater damage to the starch (although this is not necessarily the case). The damaged starch grains already swell in the dough and are thus available to the amylases. Intact starch grains are not.
3. Which particle size is better -90 or 150 microns?
That depends on the properties you want the flour to have. Smaller particles usually mean more damage to the starch if the small size was achieved with ordinary cylinder mills. This results in greater water absorption and better breakdown by enzymes and yeast, but also reduced stability of the dough. In coarser flours there is not only less damage to the starch; the larger particles also swell more slowly, with the result that the doughs stiffen subsequently and thus become more stable. Coarser flours also cause less dust and have better flow properties.
4. How does the milling yield (extraction rate) affect protein and ash? Is there some correlation between the protein and ash content of flour?
Endosperm protein and the mineral content decrease from the outside of the kernel to the centre. At higher extraction rates, the amount of the aleuron and outer endosperm layers is larger than in flour from low extraction rates. This means that ash and protein increase with the extraction rate. They are both correlated to a certain extent.
5. Why should the germ be removed from the kernel before milling? Why is there a difference in shelf-life between white flour and whole meal flour?
The germ contains about 10% lipids, mostly unsaturated. The milling process would destroy the structure in which the lipids are bound, exposing them to atmospheric oxygen. Rapid oxidation (both enzymatic and non-enzymatic) and thus rancidity would occur. Whole meal flour containing the wheat germ is therefore less stable than white flour.
6. Why does flour from the wheat of a new crop/harvest display different attributes from those of flour from wheat that has been stored for several months?
Maturation of flour is a natural process caused mainly by exposure to atmospheric oxygen. In almost all cases freshly milled flour has a much poorer performance than flour stored for 2 weeks.
 7. Is there any way of adding chemicals at the tempering stage, i.e. some water-soluble type, to achieve a whitening effect?
There have been partially successful attempts to improve the removal of the bran by adding enzymes to the soaking water, which would result in a brighter colour of the flour. The author is not aware of any trials with oxidizing substances such as chlorine, benzoyl peroxide or hydrogen peroxide. The use of oxidizing agents might have some effect on the colour, but access to the carotenoids of the intact kernel is probably limited, so the approach would not be very effective.
8. Why does the volume yield fall as the degree of extraction increases, although the protein content rises with higher extraction?
The proteins of cereal are unequally distributed over the layers of the grain. The water insoluble protein fractions glutenin and gliadin that are important for baking are mainly in the endosperm, whereas the aleuron layer, although rich in protein, contains mainly water-soluble proteins that do not improve the baking properties.

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.



Question and Flour Problems : Culvitation, Harvest and Wheat Supply


1.Is there a connection between soil characteristics and the quality of wheat?
Wheat needs good soils that ensure an adequate supply of nitrogen to the plant. Soil quality can be improved with suitable fertilizers and by the right choice of the preceding crop.

2. How do the weather and fertilization affect the properties of gluten?
Nitrogen fertilization and cool weather increase the amount of the softening gluten component gliadin. In warm, dry conditions more glutenin is stored, and this results in short and dry dough properties.

3. What are the principles for storing freshly harvested wheat?
At least the worst of the dirt and black dockage should be removed before the wheat grains are put into storage. The moisture content should also be measured so that excess water can be reduced by drying or regular turning over with the pneumatic system to prevent the growth of micro-organisms and other pests. The moisture content should be adjusted reliably to a level below 14%; then the wheat can be stored for some long time without loss of quality.

4. Which countries are the largest exporters of wheat?
In 2003-2004 the USA exported the largest quantity of wheat (31% of world wheat exports), followed by Canada (16%), Australia (15%), Argentina (8%) and the UE (7%).

5. Which countries import the largest quantities of wheat?
Egypt and Brazil with 6 million tons, closely followed by South Korea (4 mio t) and the Plippines (3 mio t)

6. What percentage of world wheat production is used for food?
Of the annual production of about 600 mio t, almost 10% is lost through rodents, insects and impoper storage conditions. About 15% is used to feed livestock, mostly in the EU, where 40% is used for feed. A small amount, about 5%, is used for technical applications, in particular secondary wheat products for the (bio)chemical industry such as starch and gluten hydrolysis products. A fast-growing non-food application of wheat (and other crops) is biofuel production. These figures leave about 70% or 400 mio t for food use.

7. Will there be an adequate supply of wheat in the future?
Although the wheat stocks seem to be falling slightly, there will probably be sufficient wheat at least in the next 2 or 3 decades because of the recovery of production areas in Eastern Europe and improved agriculture in China and India. By the end of this period, improved productivity of the wheat plant resulting from genetic modification may ensure a stable supply for a growing number of consumers.

8. Will China become a major wheat exporter in the near future?
Although the wheat imports dropped sharply from almost 12 mio t in 1995 to 400 thousand t in 2003, imports have recently risen again because of rapidly increasing demand. The consumption of wheat products increases as the average income rises. The trend is supported by the still slowly growing population. So it is rather unlikely that China will soon become a wheat exporting nation like EU, for example.

9. When does the new wheat sesason of the major wheat exporting countries start?
Even within one wheat-exporting nation there are broad harvesting seasons, with Argentina probably showing the sharpest division between the old and the new harvest; this is due to the comparatively small wheat planting zone. Furthermore, the winter wheat harvest usually starts and ends approx.. 6 weeks earlier than the harvest of spring wheat.



10. How does fertilization affect gluten properties?
Nitrogen fertilizers increase the overall protein of a variety, but the general properties are not changed: a normal gluten remains normal, with higher energy levels in the Alveogram and Extensogram; a soft gluten becomes even softer. The latter is due to an increase in gliadin, the soft component of gluten.

11. Can the resistance of wheat towards disease significantly be reduced by conventional breeding, or only by genetic modification?
Breeding for resistance has always been a major target of the breeders, but the achieved results certainly can be improved, either by further breeding or by genetic modification through methods of modern biotechnology.


Milling and Baking Quality of Wheat


Milling Quality of Wheat

Important properties are :

1.Purity of the wheat, i.e. dockage or Besatz and other impurities
The lesser the admixture, the higher the value of the wheat. Mechanically operated apparatuses (e.g. Granotest) have been developed in recent years to ascertain the percentage of impurities. The evaluation is done by a standard method.

2.Test weight (bushel or hectoliter weight)
The viewpoints differ greatly as to the significance of these factors to milling. It is in any case an accepted fact that these factors are not always indicitive as to the milling quality of wheat.

The hectoliter weight of a first class wheat can e.g. decrease from 81.5 kg to 72.5 k, merely through contamination on with small quantities of powder (sand, dust). The milling quality is not necessarily reduced in this case. Vice versa variations in the test weight due to oily substance are also noticeable. It is generally known that hectorliter weight (HL) is also influenced by moisture content, decreasing by 0.4 kg every percent of water. The HL-weight increases again during drying, but will not attain the original value again, due to permanent deformation of the kernels.

Test were made by Bruckner for the purpose of substituting the unreliable test weight by other better systems, but these were not generally acceptable. That is the reason why the test weight system is still used today as a basis for evaluation. A high test weight is always a certain recommendation for the corresponding wheat. A correlation to the milling value can exist within one and the same type of wheat measured under standardized conditions.



Note :
1 U.S. Bushel of an average weight of 60 lbs = 27.215 kg
1 quarter = 290.8 Liter

The average specific weights of the various parts of a wheat kernel are:



3. Vitreous Kernels
Wheats with a vitreous or glassy cross-section are generally preferable. Vitreousness indicates a compact kernel composition, a higher protein and a good semolina structure. Especially important in Durum wheat. Vitreousness can decrease under the influence of moisture and heat, even in the field. The % vitreous kernels is an important factor determining the quality of Durum wheat. Kernels can be partly vitreous and partly mealy.

4. Moisture Content of Wheat
Moisture content has a marked influence on flour yield, apart from its importance in the storage of wheat. Of course the higher the moisture content of wheat, the lower the amount of dry matter in the kernel. Flour can only be produced from the latter. Furthermore, if distributed too evenly in the whole kernel, moisture will cause trouble in the separation of the endosperm from the bran.

Another point is the control of the most favorable moisture content immediately before milling. No dry matter is lost in this case and this conditioning simplifies milling a great deal.

5. Flour Content of Wheat
The potential flour content of wheat can be determined fairly exactly by test milling in the BUHLER Automatic Laboratory Mill MLU-202, combined with an analytical test of the flour and the offals. This will be found to vary between 77 and 84% (on a dry matter basis = d.m.) according to kernel development. Lower results are of course obtained with abnormal kernels.

Baking Quality of Wheat
This method of evaluation can as a rule be performed with the flour obtained by test milling on the above mentioned Laboratory Mill. Wheat grains and flour, or doughs are subjected to chemical and physical analysis. The results can additionally be confirmed by a baking test if carried out by a competent baker.

A difference is made between rapid methods (e.g. Sendimentation test of Zeleny, gluten washing with the determination of the swelling figure, etc.) and more elaborate methods. It is obvious that the rapid tests can only give an approximate picture of the whole quality complex. This can be valuable in commercial practice though, if carried out exactly as prescribed.


Quality Survey Soft Red Winter Wheat 2017

Survey Overview of Soft Red Winter

Weather and Harvest: Soft red winter wheat (SRW) is grown over a wide area of eastern United States. Thearea seeded to SRW in fall 2016 for the 2017 harvest is estimated by USDA at 5.6 million acres (2.3 millionhectares), down from 6.6 million acres (2.7 million hectares) seeded for the 2016 harvest and well below the five-year average SRW planted area. The reduced area is attributed mainly to choices made by growers based on commodity prices. The 2017 SRW production, estimated at 8.3 million metric tons (MMT), is down from 9.4 MMT in 2016 and is well below the five-year average. However, USDA estimates that the total SRW supply (excluding imports) for the 2017/18 marketing year is 4% higher than 2016/17 because of higher 2017/18 beginning stocks.

Planting proceeded at a slightly slower than normal pace in fall 2016. However, the crop was in good condition by late fall with more than 90% of winter wheat rated fair to excellent in five of the six SRW survey states where wheat crop conditions are reported by USDA. While some of the southeastern SRW area was dry through the winter months, ample rain in March through early June provided adequate moisture for crop development. The beginning of SRW harvest was delayed somewhat by rain, but once started, harvest progressed rapidly.

Survey Methods: Sample collection and analysis were conducted by the Great Plains Analytical Laboratory, Kansas City, Missouri. In 2017, 270 samples were collected from elevators in 18 reporting areas across eleven states. Alabama and Tennessee were surveyed in 2017 for the first time. Test weight, moisture, protein, thousand kernel weight, wheat ash and falling number were determined on all individual samples, and the remaining tests were determined on 18 composite samples. The results were weighted by the estimated production for each reporting area and combined into “Composite Average”, “East Coast” and “Gulf Port” values. Gulf Port states include Alabama, Arkansas, Illinois, Indiana, Kentucky, Missouri, Ohio, and Tennessee, and accounted for 79% of the 2017 SRW production in the states surveyed. East Coast states include Maryland, North Carolina and Virginia and represent the remaining 21% of production in the states surveyed. The states surveyed account for an estimated 77% of total 2017 SRW production.

Wheat and Grade Data: When analysis results are weighted by estimated state production, the average gradeof all samples collected for the 2017 SRW harvest survey is U.S. No. 2. The weighted average test weight is 59.1 lb/bu, above the five-year average and the 58.6 lb/bu average of 2016. The Gulf Port average of 59.2lb/bu is similar to the 2016 average and above the five-year average of 58.6 lb/bu. The East Coast test weight average of 58.6 lb/bu is above both last year and the five-year average. The Gulf dockage value of 0.3% is lower than any recorded in the previous five years. Other grade factors as well as moisture and dockage for both areas are similar to or better than the five-year averages.

The Composite average wheat protein content of 9.5% (12% moisture basis) is similar to last year and only
slightly below the five-year average of 9.8%. The 2017 East Coast and Gulf Port protein averages are similar. However, the East Coast average protein of 9.4% is below the region’s 2016 and five-year averages, while the Gulf Port average of 9.5% is above the region’s 2016 average of 9.1% and slightly below its five-year average of 9.7%. The Composite average falling number of 319 seconds is below 2016 but above the five-year average and indicates a generally sound crop. Fewer than 20% of samples had a falling number below 300 seconds in 2017, and only 4 of 270 were below 250 seconds. The Composite DON average of 0.4 ppm is below the 2016 value of 0.6 ppm and well below the five-year average of 1.3 ppm, indicating that the crop sampled is relatively free of DON. The East Coast value of 0.8 ppm and the Gulf Port value of 0.3 ppm are both below last year’s values and five-year averages.

Flour and Baking Data: The Composite, East Coast and Gulf Port Buhler laboratory mill flour extraction averages are above 2016 but below the five-year averages. The Composite farinograph peak and absorption values are similar to five-year averages, but the stability value of 2.2 min is slightly shorter than last year and the five-year average. The Gulf Port peak and stability averages of 1.3 min and 2.4 min, respectively, are similar to last year and the five-year averages, while the East Coast peak and stability values of 1.2 min and 1.7 min are both shorter than last year and the five-year averages. The Composite and Gulf Port alveograph W values of 92 and 93, respectively, are higher than the five-year averages of 80 and 79. The other Composite, East Coast and Gulf Port alveograph values are all similar to the respective five-year averages given the variability of alveograph analysis. The Composite and Gulf Port cookie spread ratios are lower than last year and the five-year averages. Average loaf volumes are all similar to last year and the five-year averages.

Summary: Although reduced planted area decreased 2017 SRW production, the crop had generally favorable growing season and harvest conditions for both East Coast and Gulf Port states. Test weight is well above average and dockage is below average. The entire crop in the states sampled is largely free of sprout damage, and DON values are all below last year and the five-year averages. Buyers are encouraged to review their quality specifications to ensure that their purchases meet their expectations.

This survey was funded by U.S. Wheat Associates and USDA’s Foreign Agricultural Service.

About U.S. Wheat Associates: U.S. Wheat Associates (USW) is the industry’s market development organization working in more than 100 countries. Its mission is to “develop, maintain, and expand international markets to enhance the profitability of U.S. wheat producers and their customers.” USW activities are funded by producer checkoff dollars managed by 17 state wheat commissions and through cost-share USDA Foreign Agricultural Service market development programs. For more information, visit www.uswheat.org or contact your state wheat commission.

Nondiscrimination and Alternate Means of Communications: USW prohibits discrimination in all its programs and activities on the basis of race, color, religion, national origin, gender, marital or family status, age, disability, political beliefs or sexual orientation. Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USW at 202-463- 0999 (TDD/TTY - 800-877-8339, or from outside the U.S., 605-331-4923). To file a complaint of discrimination, write to Vice President of Finance, USW, 3103 10th Street, North, Arlington, VA 22201, or call 202-463-0999. USW is an equal opportunity provider and employer.






















Grist Optimizing and Unlocking Baking Potential of Flour

Every flour mill faces a plethora of challenges affecting its business operations. Some of the challenges may include inconsistent flour quality, need to enchance flour quality, raw material price fluctuations, wheat purchasing costs, non-optimal flour extraction rates, new product development, and need to innovate. All these desirable business outcomes are connected to three main decision criteria: wheat sourcing, wheat gristing and flour correction. The interrelationship between these three factors and business outcomes are depicted in picture below :
Optimization of grists costs and flour baking performance

Depicts the interrelationship between wheat sourcing, wheat gristing, flour correction and major business deliverables or expected outcomes from a mill. Together, these factors and outcomes can help optimize costs, standardize flour performance and support new product development. Because of their performance predictability, baking enzymes are also an attractive option during gristing consideration at the flour mill.

Smart purchasing of wheat is vital for the profitable and sustainable running of any flour mill because it is intrinsically linked with grain price through mill operational protocols and customer expectations. Wheat procurement and purchase, however, involve both risk and considerable amount of investment both in time and mony.

The fact that wheat has become a major commodity in world markets can result in high price volatility. It therefore becomes more important to purchase through reputable exporters or intermediaries. Inherent knowledge of the origin, source and specification of any given wheat is also extremely important.

Contracts involving international transportation often contain abbreviated trade terms that determines which party (buyer or seller) owns the responsibility for the loading, shipping and insurance costs as well as when the risk of loss shifts from the seller to the buyer. Generally speaking, most wheat is traded in a FOB (Free on Board) basis-wherein the sale is considered complete at the seller’s shipping dock and thus the buyer is responsible for freight costs and liability (also known as FOB-origin).

Other contract terms exists. Buyers who want to avoid the hassles of chartering vessels may want to consider CFR (Cost and Freight) or CIF arranges for the carriage of goods by sea to a port of destination and provides the buyer with the documents necessary to obtain the goods from the carrier. Same is true for CIF, the difference being in that the latter the seller is responsible for buying marine insurance against the risk of loss or damage to the goods during transit (liability), whereas in the former contract type this is not the case.

Traditionally, FOB prices for wheat are quoted is US dollars with payment made in the same currency against a Letter of Credit (LC). The LC incurs higher bank charges but also assures the seller that the shipment will be paid for. Buyers and sellers who have over the years developed an understanding may consider direct payment to save costs.

The number of wheat varieties and sources is both diverse and convoluted with the geographical position of each mill largely determining which wheat they can source. In an ideal world, each company would be able to construct a wheat buying matrix similar to the one in Table below :
 
Wheat buying matrix based on the cost at 1st break

There are many ways to understand and thus adopt the approach to wheat purchasing as shown in table above, both moisture and extraction rate have been allocated a predetermined value of 12% and 80% respectively, extensive knowledge and experience has shown this to be an excellent starting point for comparison.

The link between test weight (TW) and extraction rate is well documented and facilitates the introduction of ‘cost at 1st break’. In other words, it reflects how much it costs each mill to get the wheat from purchase source onto their 1st break rollers. The number of mutable parameters is many and varied. Further, moisture and foreign matter (FM), the cost of shipping water and screenings across the globe may soon add up.
Cost Calculation at 1st break 

At first glance looking only at protein and the subsequent FOB price for the two wheats in picture above. It appears that the German 12 is not only cheaper but potentially the most economical choice-particularly with a USD 32 spread. The breakdown of cost, however, is not quite as simple as that. Once additional freight charges come into play, an allowance is made for nearly double the level of screenings and when the lower TW and resulting loss in extraction is taken into account, the actual bottom line cost comes out in favor of AH 12.

Cost at 1st break is just one way of predetermining cost. There are many others-1st break raw, protein on a moisture free basis (MFB), wet gluten (WG), extraction ration and even baking score-which allude to end user considerations and expectations.

The primary driver behind sustainable wheat sourcing has always been to achieve a reduction in protein costs and to attain a positive result in mill profitability by doing so.

The combination of a number of wheat from various origins in the gristing process is fairly common practice in the milling industry. Picture below illustrates the potential savings per annum by switching from a 100% German grist to one that contains a blend with 30% Russian. The spread in the FOB price and the resulting cost per ton of flour opens a window of opportunity, allowing a 70:30 combination to perform on an equal footing in terms of quality, performance, stability and fermentation tolerance. Experience has shown this can be achieved by incorporating micro ingredients to the value of USD 3, which in this example generates a delta saving of USD 14 per ton of flour and a substantial benefit to the bottom line.

Maintaining baking performance of wheat flours with lower protein (example)

From a more contextual viewpoint, the wheat procurement officer deliberating about switching from his current wheat to one than that is USD 30, USD 20 or even USD 10 less expensive  might want to consider that an enzymatic solution somewhere in the range of USD 5 – USD 10 of micro ingredients in the vast majority of cases will be able to bridge the gap in quality. It will not only drive down wheat purchasing costs but also drive up profitability.

In essence, the concept of unlocking full baking potential of flour is based in rationalizing and utilizing knowledge of wheat costing, wheat quality and understanding enzyme functionality to be able to produce flour with desired characteristics in a cost-effective manner.

A constant challenge for millers is to produce flour with consistent baking properties. In addition, they face the challenge of manufacturing a large range of flour types and managing production costs. By supplementing flour with additives and processing aids, millers can address these issues.

Flour correction is the supplementation of flour using certain micro ingredients, chiefly ascorbic acid, malt, soya flour, vital wheat gluten, and enzymes, to attain consistent baking performance. Further, they help develop new products with enhanced properties to meet the demands of bakeries, confectionery

Further. they help develop new products with enhanced properties to meet the demands of bakeries. confectionery producers. pasta manufacturers and others. The main drivers for flour correction include the following: 
1. inconsistent wheat quality arising from genotypic differences combined with agronomic growing conditions and environmental effects
2. Need to standardize flour performance to produce bread or other wheat-based products with consistent quality
3. Lack of flexibility to improve flour quality in industrial bakeries
4. End user requirements for different flours to produce an extensive range of products
5. Cost savings from flour performance upgrade 

There are a number of factors which should be taken into consideration when flour correction treatment is applied:   
1.Flour specifications and standards in the target market
2. Availability of test bakery
3. Availability of instrumentation for measuring flour quality (Farinograph. Alveograph, Mixolab, Falling Number Test, Extensograph, etc.)
4. Predominant dough making procedures and the assortment of baked products
5. Local food ingredient regulations i.e., list of permitted food ingredients and flour improver habits in bread improver applications in industrial and artisanal bakeries (types, formulations, dosages, performance, etc)
6. Main concerns and needs of flour among end-users in relation to the finished product requirements

Success of flour correction depends on close cooperation between flour mill and flour buyer (industrial bakery, artisan bakery, pasta factory, biscuit factory, frozen dough producer, etc.). good knowledge of end user needs and requirements regarding flour quality. and expertise to manage flour functionality to achieve the desired properties. 

Flour treatment is carried out for two main purposes: 
1. Flour adjustment to diminish the effects of inconsistent wheat quality  variations in grist composition - with the view that different grists  deliver agreed and stable quality
2. Production of specialty flours for different end users 

Ingredients used at flour mills and bakeries are often the same. The main difference lies in the dosages range: 10-100 ppm at the mill; > 100 ppm at the bakery. It is therefore, critical to maintain dosage levels of enzymes and other micro ingredients being incorporated at the flour mill to moderate amounts to realize efficient flour correction and prevent their overdosing at the bakeries. 

Enzymes not only aid in flour improvement, but also in providing an efficient and natural way to cope with raw material cost and quality fluctuations.



Wheat Damage

Immature and Frost Damaged Kernels
These kernels are usually found in Manitoba wheat No. 5. This normally ground for disqualification . they are a cause of poor flour yield and dark flour color, but they promote gas production in the dough in yeast fermentation. Frost damaged kernels are usually blistered on the outside.

Sprout-Damaged Kernels
These are wheat kernels that have begun to sprout or germinate in the wheat ear out in the field as a result of continuous high moisture. These kernels are similar to malting-barley kernels. The internal break-down has already begun, thanks to the activity of strong enzymes. Dough made from sprouted wheat flour are sticky, due to excessive amounts of alpha-amylase.

Heat-Damaged Kernels
These are kernels with a brownish endosperm, caused by spontaneous heating during wheat storage and strong respiration. A dark colored flour is the result. Really burnt (carbonized) kernels are occasionally found. These are produced by over-heating in grain driers operated on the direct flame principle. In cases where only the germ under the bran is dark, this is due to fungi.

Bug Wheat
The kernel is punctured in the field by a flat bug (8-13 mm in length) during the actual growth stage. A liquid (an enzyme) is introduced into the kernel as the bug sucks out the contents of the kernel. In any case this liquid dissolves the gluten around the point of puncture, which is easily recognized externally by a small red spot, with a yellowish halo around it. Doughs made from flour from bug damaged wheat have a tendency to flow and are difficult to bake. 2% bug punctured kernels are sufficient to cause trouble.


Antidote : Many of the suggestions are of practically no use (addition of acids, formaline, large amounts of kitchen salt). The best results are obtained with :
a.conditioning of the wheat at higher temperature
b. additions of higher doses of bromate, ammonium persulfate, ascorbic acid, and so forth, to the flour.

A certain improvement can be achieved with the above mentioned means, but a complete elimination of the damage is not possible.

Detection : yellow colored areas on the kernel with a clearly visible red spot (point of puncture) in the middle. The gluten is sticky and extensible to an unlimited extent after 24 hours.  Dough reach a flowing stage within 1-2 hours. Flour derived from sound kernels. Bug damaged wheat is mostly found in wheats from Russia and the Balkan Countries, practically never in American and seldom in western European domestic wheats.

Grain Desease
Smutty kernels : the interior of the smut balls consists of a black powder, nothing but fungi spores with a herring-like smell. Such wheat is called smutty wheat and must be cleaned very carefully.

Weevily kernels : kernels damaged by the grain weevil and other pests. This damage is likely to increase through rapid reproduction during storage. Weevils in grain to be milled increase the insect fragment count in the flour (filth test) that could cause difficulty in marketing the flour in certain supply areas (export, large scale consumers).

Broken kernels : these kernels are mainly produced during threshing and during the transport of grain. Such kernels will give a dark flour of objectionable odor, as the break surfaces are dirty. If these kernels are scoured carefully by centrifugal action, the dirt will be rubbed off the break surfaces. It is thus possible to mill the broken kernels together with the sound ones. Broken kernels are excellent food for microorganisms.

Pesticides
Pesticides are used to eliminate insects in grain and granary products in silos. Mills and bakeries. These are products that easily develop toxic gases, which can be eliminated by aeration and in any case leave little or no residue.

The word sanitation is used to cover the work necessary to keep machinery, buildings, and finally all products, free from insects. The trend is towards through gassing of a mill to exterminate all signs of life including insects eggs, followed by periodical spot fumigation. The most comprehensive work on the subject is no doubt the book of Kurtz & Harris.

The filth test enables one to distinguish between grain infestation and later infection of grain products. Since this method is not yet very easy to find in journals.

A promising new solution is irradiation with Gamma Rays, which are even shorter than X-rays, but do not penetrate very deeply, so that only thin layers of product can be treated. Gamma rays have the great advantage of not leaving any chemical residue and of the treatment not being strong enough to form radioactive products. Actually experimental work is going on in the USA (Savannah, Ga. ) and in various European countries, including Switzerland. It needs higher doses per gram to kill bacteria and insect eggs than man. Since the Cobalt-60 source used emanates rays day and night, a plant must be fed continuously. Thus the future may lie in mobile plants. Cost of plant and operation are still quite prohibitive, but the future will surely see a reduction in these prices.



Storage of Wheat and the Problem Associated with it

The storage of the enormous grain stock necessary for the huge masses of people today is practically always done in closed silo bins. One differentiates between : high constructions and low-built cells, with or without aeration facilities.

The grain kernel is a living organism which breaths (respirates). The microorganisms (bacteria and mold (fungi)) living on it, also breath and play an important role. Heat, as well as water and carbon dioxide is produced during respiration, in the course of which oxygen of the air surrounding the kernel is consumed. The respiration intensity increases with increasing moisture contents, and also with increasing temperatures. It can be clearly seen that the respiration intensity and therefore also heat development are both very small at a moisture content of 14%, whereas the intensity increases quickly above 15%. A temperature increase has a similar effect on respiration intensity as does increasing moisture content. A rapid increase will occur though, if moisture and temperature increase simultaneously, resulting in the following sequence. Over 14% moisture content, temperature above 120 C:
a.More or less active respiration with water, carbonic acid and heat development, depending on moisture. Heat cannot dissipate, temperature of the wheat increases, e.g. to 200 C.
b. More intensive respiration than before, temperature increases continuously, e.g. to 250 C, as does that of water content.
c. still more intensive respiration than in case b), due to higher temperature and water content, a more rapid temperature increase, e.g. to 300 C.
d. Livelier respiration than in case c), due to higher temperature, a more rapid temperature increase, e.g. to 400 C. The endosperm of the wheat kernel begins to turn brownish
e. Further temperature increase to 50 – 700 C and higher. Kernels become brown, microorganisms die off, respiration comes to a standstill. The wheat lot is spoiled, color and baking properties are damaged.

The wheat moisture content should not exceed 14% in silo storage, in order to avoid such chain reactions; the wheat temperature should also be as low as possible, corresponding to a relative humidity of the air surrounding the kernels of about 65%. No mold fungi can develop on the kernels at this relative humidity, this will occur however at approximately 75% (corresponding to approximately 16% wheat moisture content). Bacteria need 90% to be able to live.

In cases where the conditions mentioned are not fulfilled, the wheat can only be stored for a limited period and only if special measures of precautions are taken e.g. aeration, during the course of which respiration heat, as well as the excessive relative humidity between the kernels can be removed continuously. Wheat with a moisture content of 20-25% can be kept sound for several weeks in this manner, until an opportunity occurs for milling it or for drying it down to 14% and lower for permanent storage. The technique of preliminary grain storage with aeration, in connection with modern harvest methods (combine harvesting), has been fairly well developed during the last few years. A disadvantage of this type of storage is the low permissible height of the grain, depending upon the grain moisture content, to avoid :
a.movement of the moisture into the upper layers with condensation and
b. the growth of fungi

Slow drying is od course preferable.
Degree of respiration of rye at various temperatures and moisture contents


More or less of a loss of dry matter will occur through respiration of the grain during storage, since the developed carbonic acid is produced at the axpense of the kernel matter. This loss is influenced in a similar manner by heat and moisture, as illustrated in picture above. It can be very great under certain circumstances (high moisture content, high temperature, long periods of storage), even if the grain looks externally sound. This source of loss is often everlooked in storage bookkeeping accounts where quantitative deficiencies are studied.