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Question and Flour Problems (Flour Components; Vitamins and Fortification)


1.What are the most important vintamins and minerals for flour fortification?
The most important vitamins and minerals for flour fortification are folate and iron. Other substances often used are the vitamins B1, B2 and niacin, and also the mineral zinc. Vitamin A is only added to flour in a very few countries, possibly for reasons of cost.

2. What is the basis for the legal requirements in countries where fortification is prescribed by law?
The legal requirements depend on the specific needs of the population in each country. These are determined in studies carried out by various organizations such as UNICEF, WHO and FFI. The FFI also recommends fortifying flour with at least iron and folate in every country.

3. How do vitamins and minerals react to storage?
Vitamins are especially sensitive to heat, moisture, oxygen and light. Nevertheless, they can be stored for at least 1-2 years in the tightly closed original container in a cool, dry place (20 0C, 50% relative humidity). Minerals store well; they can be kept for at least 2 years. Mineral and vitamin premixes should be stored in the original container in a cool, dry place and used within a year.

4. What fluctuations in the analytical values are usual or acceptable?
The fluctuations in the analytical values for a vitamin and mineral premix, and for the individual components of the premix, are usually between 5 and 10%, depanding on the vitamin and the analytical method used . in the case of flour, absolute deviations of 1 mg /kg may occur if the vitamin content is less than 10 mg/kg; if the vitamin content is higher the fluctuations may be up to 10%.

5. Why do human beings need vitamins?
Vitamins play an important role in many processes in the human body, such as metabolism to generate energy, in the formation of cells, and in the muscles and the nervous and immune systems.

6. Which vitamins are present in wheat grains?
Wheat grains contain numerous minerals and the vitamins ẞ-carotene (pro-vitamin A), biotin, vitamins B1, B2, B3 (niacin), B5 (pantothenic acid), B6, B9 (folate), vitamin E and vitamin K.

7. How does the vitamin content of the flour change at a higher degree of extraction?
A high degree of extraction causes a large proportion of the minerals and vitamins to be removed with the outer layers of the grain. Some vitamins are then only present in small traces or are lost altogether. (Iron is reduced to 1/3, folate to 1/5, and vitamin A and ẞ-carotene to as little as 1/10).

8. Do the active substances in flour improvers and baking agents influence the physiological effects of vitamins?
The constituents of food may effect the absorption of minerals. Ascorbic Acid, for example, can have a positive effect on the uptake of iron, whereas phosphate inhibits iron absorption.

9. Are the vitamins in the grain stable?
Yes, as long as the grain is undamaged. The influence of the pH, atmospheric oxygen, light and temperature – i.e. the conditions under which the grain is milled – reduce the content. Folate may be lost altogether. In the case of baking flours a loss of 70-90% has to be reckoned with as compared to whole meal. The higher the mineral content of the flour, the more vitamins are preserved.

10. What is the purposes of fortifying light coloured flours with vitamins?
It is generally agreed that fortifying staple foods with specific additives to stabilize the health of the population is an important task of health policy. However, this could not be done until it became possible to produce vitamins synthetically. Wheat flour was first treated with B1, niacin and iron in the USA in 1938, and subsequently in the United Kingdom. There are now obligatory regulations in the USA and Canada. In the countries of the European Union, flour fortification is not subject to any restrictions.

11. Why is folate important?
Folate is involved in the metabolism of amino acids and the synthesis of DNA and choline. During pregnancy it helps to prevent the occurrence of defects in the neural tube (the precursor of the brain and spinal cord). Folate also plays an important role in the prevention of cardiovascular disease by neutralizing the dangerous intermediate product homocysteine.

12. Which forms of iron can be used in flour fortification , and what is the difference between them?
The most common are ferrous sulphate, ferrous fumarate and elemental iron powders. They differ in respect of bioavailability, iron content, price, and the potency of their reaction to other flour ingredients.

13. Can micronutrients be added together with other flour improvers as one premix?
Micronutrients should be added separately from flour improvers to prevent the destruction of vitamins through interaction of the improver with the nutrient premix.

14. Are nutrients stable?
Vitamins are sensitive to heat, light, humidity, oxidation, acids and alkalis; see also question number 3. Minerals are generally very stable, but iron may be converted from its reduced form (Fe II) into its oxidized form (Fe III) which may have lower bioavailability.

15. How can I ensure that iron added as part of a premix is not detected by the metal detectors, or picked up by the magnetic separators?
Only iron in its pure form (mostly reduced iron) is picked up by the magnetic separator. Iron salts like iron sulphate or iron fumarate are not ferromagnetic. In no case should the iron be detected by the metal detector. The particles are too small to create a measurable signal for detectors in use today. If there is a signal, this must be due to a to large particle, or very poor distribution of the iron powder in the flour.

16. Why do baked goods made from my iron-enriched flour have specks/spots?
a. Larger iron particles oxidize (“rust”) on the surface of the baked product.
b. Iron catalyzes chemical reactions, e.g. oxidation of phenolic compounds that turn into dark pigments.




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