Minerals, essential for our body. In this slide changes of minerals during processing of foods are given. Check that out for gathering information and knowledge. It will be helpful.

1. Changes in Minerals During Processing of Foods
Submitted by
Towkir Ahmed Ove
M.Sc. In Food Science & Nutrition

2. Minerals
a mineral is a chemical element required as an essential
nutrient by organisms to perform functions necessary for life.
Minerals originate in the earth and cannot be made by living
organisms. Plants get minerals from soil. Most of the minerals
in a human diet come from eating plants and animals or from
drinking water.

3. kinds of minerals
1) macro minerals
Macro means "large" in Greek (and our body needs larger amounts of
macro minerals than trace minerals). The macro mineral group is made
up of calcium, phosphorus, magnesium, sodium, potassium, chloride,
and sulfur.
2) trace minerals
A trace of something means that there is only a little of it. So even
though your body needs trace minerals, it needs just a tiny bit of each
one. Trace minerals includes iron, manganese, copper, iodine, zinc,
cobalt, fluoride, and selenium.

4. Importance Of Minerals
 proper composition of body fluids,
 the formation of blood and bone,
 the maintenance of healthy nerve function, and
 regulation of muscle tone, including cardiovascular system.

5. EFFECT OF PROCESSING ON MINERALS
The bioavailability of minerals is mostly affected by the processes of
1. milling,
2. soaking,
3. cooking,
4. germination,
5. fermentation, and
6. heat processing.
All of the above processes influence mineral bioavailability either
directly by affecting their solubility or indirectly by destroying the
inhibitory effect of phytic acid or tannins.

6. 1. Milling
 Conversion of whole wheat to white flour results in 16--86% loss of iron, zinc,
copper, magnesium and selenium
 The phosphorus content of phytic acid greatly dictates the amounts of minerals
absorbed, especially iron and zinc.
 Although losses of minerals are substantial during milling, mineral
bioavailability can improve due to the reduction in the phytic acid.
 Pearling of sorghum also increases iron absorption due to the reduction in
polyphenol and phytate content.
 Phytic acid, also known as phytates, or IP-6 – is the storage form of
phorphorus in plants. Phytic acid binds to minerals such as zinc, iron,
magnesium, calcium, chromium, and manganese in the digestive tract, making
them unavailable. When we consume foods with phytic acid, our ability to
absorb the minerals is impaired and mineral deficiencies and bone loss may
result.

7. 2. Cooking
 Though minerals are not lost due to heat, but are usually leached if cooked in
boiling water.
 Zinc and iron losses by conventional cooking of broccoli, spinach, sweet
potato.
 Cooking might improve mineral bioavailability by increasing solubility due to
cell wall disruption, protein denaturation and release of organic acids. For
example, iron bioavailability increased by at least 200% when vegetables such
as broccoli, kale and cabbage were cooked.
 Hydrochloric acid extractability, an indicator of mineral availability, was
greatly enhanced for calcium and zinc by cooking and blanching of spinach
and amaranth leaves.

8. 3. Soaking, Germination, and Fermentation
 Mineral availability from cereal grains can be improved by hydrolyzing phytates
during processing.
 Calcium, zinc, iron, manganese and copper availability increased when pearl millet
was fermented.
 Reduction of phytate by germination and fermentation was shown to improve iron
availability from soy beans and wheat products.
 Sorghum, due to its high content of phytate and tannins, has minerals of poor
availability. However, tannin levels can be reduced by soaking and germination,
both of which improve iron and zinc availability from sorghum products.

9. continued
 Fermentation improves the bioavailability of minerals not only by reducing the
phytate content but also by producing lactic acid which improves mineral
solubility.
 Fermentation of milk with Staphylococcus thermophilus and Lactobacillus
bulgaricus increased zinc availability from 6.3% to 12.5%. The increase in zinc
solubility was attributed to the fermentation of lactose to lactic acid which
either increased zinc solubility or decreased the binding of zinc to casein.

10. 4. Storage
 Freezing cooked vegetables for six months had no effect on iron or
zinc availability.
 One of the factors limiting the expanding consumption of beans is
the development of a textural defect when beans are stored under
relative humidities and high temperatures prevalent in tropical
countries.

11. 5. Fortification
 Iron bioavailability from infant cereals can be improved by adding ascorbic acid, a
well-known enhancer of iron absorption.
 The effectiveness of ascorbic acid in increasing iron absorption depends on the
type of food and the amount of inhibiting factors present in the food.
 Fifty mg of ascorbic acid increased iron absorption from infant cereals, maize, rice
and wheat.
 Ascorbic acid was less effective in enhancing iron absorption from quinoa because
of its high phytate and polyphenol content.

12. 6. Heat Processing
 More than 50% if the manganese, cobalt, and zinc may be lost during canning of
spinach, beans, and tomatoes, if the liquid is not consumed.
 Use of hard water for processing and cooking can result in an increase in the
calcium or magnesium content of foods, while use of softened water can result in
an increase in the sodium content.
 Cooking and baking can destroy ascorbic acid and its effect on iron availability.
 In vitro studies have shown that Maillard reaction products, produced during
browning, bind with zinc. The degree of binding is related to the extent of
browning and the nature of the proteins found in the food.

13. Continued
 Extrusion processing of cereals can cause an increase in iron content due to
contamination from the extruder.
 The process can also increase mineral bioavailability by reducing the phytate
content of food.
 Extrusion cooking reduced the phytic acid content of cereals from 66-79% to
2~50% of the total inositol phosphates, resulting in increased iron
bioavailability.

14. Conclusions
All foods that processed are subjected to nutrient losses. However,
processing can increase nutrient bioavailability due to inactivation of
anti nutritive factors. In conclusion, food processing practices can
generally be beneficial in terms of increasing mineral availability but
sometimes they can impose detrimental effects if proper treatment is
not met.

15. Thank You