Agriculture Reference
In-Depth Information
T A B L E 2.10. Minerals Found in Foods in Milligrams
a
Quantities
Chemical
Formula
Ionic
Form
Common
Mineral Form
Mineral
Ca
2þ
Calcium
Ca
CaCO
3
Mg
2þ
Magnesium
Mg
MgCO
3
Phosphorus
b
P
MPO
4
CaHPO
4
K
þ
Potassium
K
KCl
Na
þ
Sodium
Na
NaCl
Zn
2þ
Zinc
Zn
ZnCl
2
Cu
2þ
Copper
Cu
CuCl
2
Manganese
b
Mn
3þ
Mn
KMnO
4
I
2
Iodine
I
KI
Molybdenum
b
Mo
4þ
Mo
MoS
2
Se
4þ
Selenium
SeO
2
a
Except for selenium, which is found in microgram quantities (mg ¼ milligrams ¼ 10
23
Se
gram, mg ¼
micrograms ¼ 10
26
gram.)
b
Commonly occur in a number of different oxidation states. M stands for metal.
blood pH. Magnesium is an important constituent of bones and other components such
as muscle and the liver. Sodium finds its major use in maintaining the proper fluid
content of the body in addition to helping to maintain blood pH. There are also
many other functions of these minerals in the body.
The trace minerals are important in the functioning of blood and enzymes. Iron is
an essential component of hemoglobin, which carries oxygen throughout the body. Zinc
and selenium are both essential components of numerous enzymes.
In addition to the above minerals that, except for phosphorous, occur as cations,
there are three important minerals, chlorine as chloride, sulfur as sulfate, and iodine
that occur primarily as anions in the body, that is, Cl
2
,SO
4
¼
, and I
2
. Chloride and
sulfate both maintain the electrical neutrality, fluid levels, and pH in the body.
Iodine on the other hand is an essential component of thyroxin, which maintains the
body's base metabolism, and thus is essential to health. Because electrical neutrality
is essential, it is rare to find a deficiency of one of these minerals if the cationic minerals
are in sufficient supply.
Some sources of these minerals are shown in Figure 2.23, and amounts of minerals
in these fruits and nuts are given in Figure 2.24. A more detailed analysis of the
major and trace minerals in almonds, guavas, and strawberries is given in
Figures 2.25 and 2.26. In both cases almonds are high in all minerals, except sodium
and selenium, when compared to guava and strawberry. Sodium is present at low
levels, 1, 2 and 1 mg, respectively, for almonds, guavas, and strawberries. Selenium
is present in microgram quantities, 2.8, 6, and 4, respectively, for almonds, guavas,
and strawberries. With this type of comparison it is always essential to keep in mind
that a major portion of the variation between almonds and fruits occurs because
of their different water contents, strawberries having higher water contents than
either guavas or almonds.
