Qualitaly

June July 2015

terms, it must have four bonds to reach

a stable condition. Two of these are the

connections made with the carbon atom

of the previous and next (-CCC-) while

the other two are normally shared with

two hydrogen atoms.

If the whole molecule was composed

in this way define the fatty acid is

saturated, which indicates that all the

bonds possible for all the carbon atoms

are shared with other atoms. If a carbon

atom to be bound to one hydrogen

atom, the other electron it would share

with the carbon atom next or previous,

forming the so-called double bond (-C

= C-). In this case the fatty acid is called

unsaturated. We’ll call him if he has one

monounsaturated or polyunsaturated

double bond it will have more than one.

The presence of one or more double

bonds within the molecule of a fat is

an advantage for our health because

it allows a degree of flexibility to the

molecule, which is exactly what it takes

to the cell in order to communicate

with other cells or receive information

biochemical from the outside. Mono or

polyunsaturated fatty acids, therefore,

are a fundamental part of our health.

The downside of unsaturated fat

is in the vulnerability to attack of

free radicals. These molecules are

particularly aggressive for physical

reasons that have lost an electron in

their peripheral orbit reaching a state

of extreme instability. In milliseconds

must recover this electron and, if not

intercepted by appropriate molecules,

antioxidants, go to take their own that

electron shared between the two carbon

atoms constituting the double bond.

Doing so, however, they damage the cell

until they kill it.

BY CATERING this can be read in

a very practical way: the higher the

polyunsaturated fatty acid composition

of a product that we treat the greater its

vulnerability to external agents, then

decays or rancid before.

About industrially preparing foods

knows this problem so that with

the processes of hydrogenation, or

saturation does is providing hydrogen

atoms to the molecule of the fatty acid

in order to eliminate the double bond

to make the structure more stable. This

would not be bad if it were not for the

fact that saturated fatty acids are the

main responsible for the damage to the

arteries known as atherosclerosis, which

over time can lead to cardiovascular

diseases also important.

OIL IS OBTAINED by pressing the

seeds of various plants, such as olive,

sunflower, peanut, corn, soybeans and

so on. That oil is the only one thar

can not require chemical processing

while all other oils derived from

seeds you need a process that is

called “rectification”. In reality it is

not a single process, but of a chain of

chemical interventions that have several

purposes. The de-gumming helps

eliminate suspensions; neutralization

away free fatty acids and reduces

the acidity of the oil; deodorization

eliminates volatile substances of

unpleasant odor; decolorisation uses

physical or chemical methods to remove

pigment or oxidation products; the

demargination gets away those fats that

have a melting point not appropriate.

For what concerns the olive oil the

great difference, in terms of quality

and health concerns the extraction

temperature. Hot extraction, much

more profitable for the manufacturer,

eliminates completely the oleic acid,

monounsaturated, true value of olive

oil. If instead the extraction is done at

cold this fatty acid is preserved, but the

yield is much lower and, consequently,

the cost is higher. This difference

can be seen from the statements read

on the label, but it may be worth

remembering that an oil of excellent

quality, not chemically treated and cold

extraction, if exposed to light after a

while ‘time rancid. For this reason, the

careful consumer will be strange find

themselves on board an oil contained

in a clear bottle, white, presented as

genuine or even labeled “cold-pressed”.

POINT OF SMOKE. The choice of the

oil cooking must be borne in mind in

this technical data represented by the

smoke point. This is the temperature at

which the fatty acid molecules undergo

changes physical, becomes saturated

and producing substances toxic to the

body.

From the organoleptic point of view the

resulting product is of lower quality.

Also in this case risk of experiencing

a contradiction because the better the

quality of the oil, and this depends on

the number of polyunsaturated fatty

acids which composes it, the more

vulnerable to saturation will be the

same and accordingly will be lower

his smoke point. One might think,

therefore, to use saturated oil because it

has a higher smoke point. Conceptually,

it would be a proper speech if it were

not for the fact that saturated fats are

in themselves harmful to health. A

few examples will help us to better

understand. The extra virgin olive oil

has a smoke point of around 210 °,

that of sunflower seeds less than 130

°, peanut oil at around 180 °, as palm

240 °.

From the practical point of view we

will act as follows. It being understood

that a fry is never a healthy thing, we

can agree to present it but if we give

quality to our work, we will make

the best possible manner; we provide

a cooking thermometer to maintain

constant the temperature of the oil

and avoid the exceeding of the smoke

point, preferring those most suited to