C. Iron as fortificant
1. Iron type Two iron forms that are commonly used in food fortification are ferrous Fe
2+
and ferric Fe
3+
. Because both of these species contain unfilled d orbitals, they readily form complexes with electron-rich components yielding species that
influence taste and bioavailability. Also, iron has the ability to undergo oxidation- reduction redox reactions that cause many of unwanted outcomes related to
taste, appearance, and bioavability Mehansho 2006. 2. Iron bioavailability and solubility
Currently, there are numbers of iron sources available as food fortificants. Based on bioavailability, these iron fortificants are classified into 2 groups. The
highly bioavailable iron sources e.g., ferrous sulphate and ferrous fumarate, which are soluble in neutral andor acidic aqueous environments but may cause
organoleptic changes such as poor product acceptability and shortened product shelf life, and those with poor bioavailability e.g., iron pyrophosphate and reduced
iron, which are less soluble in water but are more compatible with the foods used as vehicle Mehansho 2006.
Table 8 Relative biological value and solubility of various irons Iron compound
Relative Biological Value RBV
Solubility g100ml water
Ferrous Sulphate 100
25.6 Ferrous Fumarate
95 0.63
Ferric Pyrophosphate 45
Insoluble
Source : Lynch and Hurrell 1990 Wikipedia 2009
From Table 8, eventough ferrous sulphate has excellent bioavailability but this iron has soluble in aqueous solution water and may affect the taste and
appearance of the finally consumed product. An iron characteristic with acceptable bioavailability but less soluble in milk solution, that is ideal for particular
fortification, seems to be offered by ferrous fumarate. Nevertheless Ferric pyrophosphate which has the least solubility is worth to be evaluated in respect to
the effect of taste and appearance of the finally consumed product. 3. Iron price indication
Based on landed prices, the price index of three subject iron that use for this
research is Iron Ferrous Sulphate, with price index 100 ; Iron Ferrous Fumarate, with price index 167 ; Iron Ferric Pyrophosphate, with price index 133.
From above price index comparison, it shows that Iron sulphate is the most economical iron fortificant. However the iron dosage in chocolate filled milk powder
should not more than 0.1 in dry matter, the cost in use of iron in final product, amongst above iron type, might not be significant different.
D. Ingredient interaction between iron and some ingredients in chocolate filled milk powder