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The quantity and quality of fat in the diet play a critical
role in maintaining human health. Several studies in literature have
directly implicated the amount and type of fat intake to specific diseases
such as cardiovascular disease, hypercholesterolemia, cancer, high blood
pressure and obesity. The largest contributor to this is TRANS FAT.
Fats and Oils as Nutrients
Countless reports concerning the negative effects of fats and oil consumption
have shifted today’s dietary focus towards fat minimization. This
is unfortunate, any student of nutrition knows that fats are essential
dietary components. Except for trans fat which should be avoided as much
as possible, other fats are essential nutrients in our balanced diet.
Excessive fat intake is detrimental but the recent success of some diet
programs such as the Atkins Diet has shown a reduction of carbohydrates
and quality/quantity of fat and can have a positive effect on weight
loss and general health.
The functional role of fat in the diet is at least threefold. First,
fat provides calorie density to the diet. One gram of fat gives 9 Kcal
of energy. Carbohydrates and proteins, provides only 4 Kcal of energy
per gram. Hence fat provides calorie density to the diet. Secondly, fats
are essential in the diet for the absorption and mobilization of fat-soluble
vitamins such as vitamin A, E, & K and fat-soluble antioxidants.
These vitamins are not utilized by the body, if fat is not available
in the diet. Thus fat is a vehicle carrying the fat-soluble vitamins,
nutrients and antioxidants in the body. Thirdly, vegetable oils are the
only sources of essential fatty acids to the body.
Essential fatty acids (EFA) are those fatty acids, which the body cannot
synthesize and need to be supplied through diet. EFA’s are the
precursors for a group of chemically related compounds, known as prostaglandins
that are synthesized in the body from EFA. If EFA is not supplied through
diet to the body, the body cannot synthesize prostaglandins. Prostaglandins
play a key role in regulating many physiological processes in the body,
such as controlling blood pressure, vascular damage in the brain and
the heart, preventing blood clot in the arteries, lowering cholesterol,
uterine contractions during child birth and menstrual cycles, inflammation
and other conditions. Fourthly, fat in the diet imparts certain textural
qualities, taste and palatability to the food. Fats and oils are integral
lubricants of foods in two ways: through use as release agents as a part
of the cooking process and as a lubricant during mastication (chewing).
Fats and oils modify flavor release and improve palatability.
Functionality of Dietary Fats
The type of fat used impacts all the functional factors. Fat molecules
consist of three fatty acids linked to a glycerol backbone, resulting
in triglycerides. The fatty acids consist of varying carbon chains ranging
from 12 carbon atoms to 18 carbon atoms, and with unsaturation ranging
from 0 to 3 double bonds. These triglycerides are termed as fat or oil.
Depending on the nature of fatty acids, the fat can be a solid fat or
liquid fat at room temperature. The solid fat will have more percentage
of saturated fats in the triglycerides and the liquid fats will have
more unsaturated fats. The term important to stability and health relate
to the degree of saturated and unsaturated fatty acids present in oil
or fat.
Saturated fatty acids (SFA) have no double bonds between carbon and hydrogen;
unsaturated fatty acids are those, which have one, two or three double
bonds between the carbon and hydrogen in the chain. When there is one
double bond it is termed monounsaturated fatty acids (MUFA). More than
one double bond is termed polyunsaturated fatty acids (PUFA). A Trans
Fat is when unsaturated fat bonds have been deformed to resemble a saturated
fat. Your body doesn't know how to process trans fat and it disrupts
all your metabolic processes.
When a fat is rich in SFA, it is solid at room temperature, such as coconut
and palm oil and when it is rich in MUFA and PUFA it is liquid at room
temperature. All solid fats tend to increase cholesterol and liquid fats
tend to favor cholesterol reduction.
Fat Requirements
Fat consumption primarily occurs through salad and cooking oils, followed
by frying fats and bakery shortenings. Now let us look into the quality
and quantity of fat required in a balanced diet. According to the American
Heart Association (AHA) the optimum intake of fat for an adult is 30%
of the total caloric intake, to come from fat. It means an adult ingesting
2000 calories of diet should be getting 600 calories (30%) or 60-65 grams
of fat per day. This quantity of fat per day is required in a balanced
diet to maintain good health.
Coming to the quality of fat, the 30% of fat should include, not more
than 8-10% Saturated fat (SFA), 10-12% Monounsaturated fat (MUFA) and
not more than 10% of Polyunsaturated fat (PUFA). Among the 10% PUFA at
least 3% should come from n-3 fatty acids (Omega 3), which are part of
the PUFA family and as 0% Trans Fat or as little as possible. Thus the
quality and quantity of fat requirements to the body is well defined.
Rice Bran Oil (RBO)
Rice bran oil is popular in several countries such as Japan, India, Korea,
China and Indonesia as cooking oil. It has been shown that RBO is an
excellent cooking and salad oil due to its high smoke point and for its
delicate flavor. RBO is known for reducing cholesterol and cardiovascular
diseases. The nutritional qualities and health effects of rice bran oil
are discussed below, and are compared with other commonly used coking
oils.
Nutritional Qualities of Rice Bran Oil (RBO)
Fats and oils act as a heat transfer medium, but also become a component
of the food. Because of this dual function, the oil must meet a number
of requirements. It must have good thermal and oxidative stability. It
must also have good flavor, good shelf life and acceptable cost. Finally,
it must have consumer appeal.
There are two types of fats we consume in our daily diets. One is invisible
fat, which comes from all natural fat present in vegetables, fruits,
cereals, poultry, meat, fish and other foods. The other one is visible
fat, which is the cooking medium, salad oils and other added sources
of oils. We have no control over the invisible fat intake. However, the
quantity and quality of visible fat intake need to be controlled to maintain
better health.
Comparing known vegetable oils and rice bran oil to the fatty acid profile
recommended by the American Heart Association, we find RBO is the closest
to the AHA recommendations. AHA recommendations are that SFA in the diet
above 10% is not good, as it tends to raise the cholesterol levels. SFA
below this 10% level is good for health. MUFA at 10% and above is good
as it maintains cholesterol levels, but below this level is not good
for health. PUFA at the 10% level is good, but too much of PUFA is known
to generate free radicals and aid carcinogenesis and hence is not good
for health. PUFA below 10% is not good, as the body needs essential fatty
acids for its metabolism.
Another component of fats and oils is the unsaponifiable fraction (unsap),
which contains the antioxidants and micronutrients of the oil. RBO has
4.2% of unsap, whereas all other oils have unsap less than 1-2%. It is
the combination of an excellent essential fatty acid profile and a high
unsaponifiable fraction that brings about cholesterol reduction. In addition
to this RBO does not produce any allergenic reactions when ingested,
as does several oils. RBO has the highest cholesterol reduction capacity
of any other oil.
RBO unsaponifiable fraction is rich in vitamin E complex, tocopherols
and tocotrienols, a unique antioxidant known as gamma oryzanol, high
quantities of phytosterols, polyphenols and squalene. RBO has a very
good shelf life compared to other cooking oils because of these antioxidants.
These compounds are nutritionally very valuable and it has been shown
to be responsible for the hypocholesterolemic effect. RBO appears to
be the richest source of tocopherols and tocotrienols. Hence RBO not
only has a good fatty acid profile, but also is a rich source of antioxidants
and micronutrients.
Hypocholesterolemic Effect of RBO
Studies have shown that RBO in the diet significantly reduces LDL cholesterol
and triglycerides; it increases HDL cholesterol (good cholesterol), inhibits
platelet aggregation and prevents cardiovascular diseases. Clinical studies
from Japan, India and the U.S.A. have confirmed these results and named
RBO as ”Health Oil”. In every 1% reduction in cholesterol,
there was a 2% decrease in the risk of coronary heart disease. Thus RBO
in the diet significantly reduces cholesterol without any side effects
known to exist with pharmaceutical drugs and is the healthiest of all
oils for human consumption.
Safety of RBO
A safety evaluation of RBO was carried out by the FDA/WHO protocol. It
was proved to be safe for human consumption, without any side effects.
RBO has earned GRAS status in the U.S.A.
Taste and Acceptability
Foods were prepared in several ways, such as deep fried, pan fried, baked
foods and salad dressings in rice bran oil. Similar foods in peanut oil,
palm oil, soybean oil, olive oil and corn oil were prepared and compared.
Taste panel, color, appearance, smell and texture were the criteria for
the acceptability of the products. RBO prepared foods scored highest
in all the panels, also rated highest shelf life when compared to the
other products. RBO was found to be more economical as less oil is absorbed
in the food, almost 20% less when compared to other oils. This lower
absorption rate is related to the viscosity of RBO, a physical quality
of the oil, which makes it light and non-sticky. The high smoke point
prevents the isomerization and polymerization of the fatty acids and
also the generation of free radicals at high temperatures. There are
many beneficial aspects of RBO that attracts consumers to utilize RBO
in their diet.
Check product ingredients for shortenings and hydrogenated oil as these
contain Trans Fats. Ask restaurants what they are using to fry or prepare
your meal. It makes a difference and your good health depends on it.
~ Please visit our order desk to purchase ~
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