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Minyak Goreng Sawit

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Minyak Goreng Sawit
Minyak sawit telah digunakan untuk makanan selama lebih dari 5000 tahun yang lalu.
Minyak sawit didapatkan dari buah kelapa sawit dan merupakan minyak nabati yang paling
banyak dikonsumsi di seluruh dunia (Chandrasekharan et al. 2000). Minyak sawit
memiliki kandungan asam lemak jenuh yang tinggi yaitu sekitar 50%. Minyak sawit
(palm oil) juga dijadikan nama asam lemak jenuh rantai karbon 16 yaitu asam
palmitat. Minyak sawit juga memiliki asam lemak tak jenuh tunggal yang cukup
tinggi. Secara lengkap minyak sawit memiliki kandungan sebagai berikut asam lemak
jenuh terdiri dari asam palmitat (C16) sebesar 44.3%, Stearat (C18) sebesar 4.6%,
asam miristat (C14) 1.0%. Asam lemak tak jenuh tunggal terdiri dari asam oleat
(C18:1) sebesar 38.7% dan asam lemak tak jenuh ganda terdiri dari linoleat (C18:2)
sebesar 10.5% (mukharjee)
Minyak sawit dikonsumsi dengan cara langsung maupun sebagai minyak
goreng dengan berbagai tingkat oksidasi. Berbagai penelitian mengenai asupan
minyak sawit segar (tanpa pemanasan) pada hewan dan manusia didapatkan efek yang
menguntungkan terhadap kesehatan. Manfaat kesehatan tersebut meliputi penurunan
resiko terhadap arterosklerosis dan thrombosis arteri, penghambatan biosintesis
kolesterol dan aggregasi platelet serta penurunan tekanan darah. Naumun, pada
penggunaan melalui pemanasan yang menyebabkan terjadinya proses oksidasi
terdapat resiko fungsi fisiologis dan biokimia tubuh. Minyak sawit yang teroksidasi
memiliki efek merugikan terutama terhadap profil lipid (Mukharjee). Walaupun
demikian Beberapa penelitian terbaru menyebutkan efek minyak sawit relatif tidak
mempengaruhi profil lipid darah apabila dibandingkan dengan lemak dan minyak
lainnya, minyak sawit dapat meningkatkan kadar kolesterol hanya jika dikonsumsi
berlebihan. Selain itu minyak sawit juga dapat menstimulir sintesis kolesterol HDL
dan mengurangi kadar kolesterol LDL (
Berbagai penelitian terbaru didapatkan
Palm oil is consumed in the fresh state and/or at various levels of oxidation. Feeding
experiments in various animal species and humans have highlighted the beneficial role
of fresh palm oil to health. These benefits include reduction in the risk of arterial
thrombosis and atherosclerosis, inhibition of cholesterol biosynthesis and platelet
aggregation, and reduction in blood pressure. However, on being used in the oxidized
state possesses potential dangers to the physiological and biochemical functions of the
body. Oxidized palm oil induces an adverse effect on plasma lipid profile, free fatty
acids, phospholipids and cerebrosides (mukharjee).
However, a sizeable and growing body of scientific evidence indicates that palm oil’s
effect on blood cholesterol is relatively neutral when compared to other fats and oils.
Palm oil raises plasma cholesterol only when an excess of dietary cholesterol is
presented in the diet. Palm oil stimu- lates the synthesis of protective HDL cholesterol
and removal of harmful LDL cholesterol.
However, a sizeable and growing body of scientific evidence indicates that palm oil’s
effect on blood cholesterol is relatively neutral when compared to other fats and oils.
Palm oil raises plasma cholesterol only when an excess of dietary cholesterol is
presented in the diet. Palm oil stimu- lates the synthesis of protective HDL cholesterol
and removal of harmful LDL cholesterol.
Minyak goreng adalah minyak yang digunakan untuk menggoreng maupun melakukan
proses memasak lainnya. Minyak goreng yang paling banyak digunakan di Indonesia adalah
minyak dengan bahan baku minyak sawit (Simatupang dan Purwoto, 1996). Minyak sawit
dapat dipergunakan untuk bahan makanan dan industri setelah melalui proses penyulingan,
penjernihan dan penghilangan bau atau RBDPO (refine, bleached and deodorized palm oil).
Minyak goreng sawit merupakan salah satu sumber lemak utama bagi orang Indonesia.
Asupan lemak penduduk indonesia terus meningkat dari 58,1 g/kap/hr pada tahun 2002,
meningkat menjadi 61,5 g/kap/hari pada tahun 2007 dan 64,7 g/kap/hari tahun 2009. Dan
hampir separuhnya berasal dari lemak tampak yang terdiri dari minyak goreng (terutama
minyak sawit), santan kelapa dan mentega (Hardinsyah 2011). Berdasarkan survei yang
dilakukan Martianto et al. (2005), rata-rata konsumsi minyak goreng di Indonesia sebesar 23
gram per hari.
Asam lemak
A fatty acid is an organic acid—a chain of carbon atoms with hydrogens attached—that has an
acid group (COOH) at one end and a methyl group (CH3) at the other end. The organic acid
shown in Figure 5-1 is acetic acid, the compound that gives vinegar its sour taste. Acetic acid
is the shortest such acid, with a “chain” only two carbon atoms long. (Fatty acid and related
terms are defined in the accompanying glossary.)
A saturated fatty acid is fully loaded with hydrogen atoms and contains only single
bonds between its carbon atoms.
PUFAs are triglycerides that contain fatty acids with two or more (poly) double
bonds. PUFAs are liquid at room temperature and, because they are not solid
fats, they are often referred to as oils. In recent decades, researchers have
discovered that the function of PUFAs in human nutrition differ based on the
fatty acid structure. The most common PUFAs are n-3 and n-6, and because
humans cannot synthesize them, they are considered essential dietary nutrients.
A polyunsaturated fatty acid has two or more carbon-to-carbon double bonds.
triglycerides (try-GLISS-er-rides): the chief form of fat in the diet and the major storage form
of fat in the body; composed of a molecule of glycerol with three fatty acids attached
Generally speaking, most polyunsaturated vegetable oils are liquid at room
temperature, and the more saturated animal fats are solid. Some vegetable oils—
notably cocoa butter, palm oil, palm kernel oil, and coconut oil—are saturated ♦; they
are firmer than most vegetable oils because of their saturation, but softer than most
animal fats because of their shorter carbon chains (8 to 14 carbons long). Generally,
the shorter the carbon chain, the softer the fat is at room temperature. Saturation also
influences stability. All fats become spoiled when ex- posed to oxygen. The oxidation
of fats produces a variety of compounds that smell and taste rancid. (Other types of
spoilage can occur due to microbial growth.) Polyunsaturated fats spoil most readily
because their double bonds are unstable; monounsaturated fats are slightly less
susceptible. Saturated fats are most resis- tant to oxidation and thus least likely to
become rancid.
Risks from Saturated Fats As mentioned earlier, LDL cholesterol raises the risk of
heart disease. Saturated fats are most often implicated in raising LDL cho- lesterol. In
general, the more saturated fat in the diet, the more LDL cholesterol in the body. Not
all saturated fats have the same cholesterol-raising effect, however. Most notable
among the saturated fatty acids that raise blood cholesterol are lau- ric, myristic, and
palmitic acids (12, 14, and 16 carbons, respectively). In contrast, stearic acid (18
carbons) does not seem to raise blood cholesterol.15 However, making such
distinctions may be impractical in diet planning because these satu- rated fatty acids
typically appear together in the same foods. In addition to raising blood cholesterol,
saturated fatty acids contribute to heart disease by promoting blood clotting.16
Benefits from Monounsaturated Fats and Polyunsaturated Fats Replacing both
saturated and trans fats with monounsaturated ♦ and polyunsaturated ♦ fats may be the
most effective dietary strategy in preventing heart disease.22 The lower rate of heart
disease among people in the Mediterranean region of the world is often attributed to
their liberal use of olive oil, a rich source of monounsaturated fatty acids. Olive oil,
especially virgin olive oil, also delivers valuable phytochemi- cals that help to protect
against heart disease.23 Replacing saturated fats with the polyunsaturated fatty acids
of other vegetable oils also lowers blood cholesterol.
Saturated fatty acids
Originally, it was postulated that all saturated fatty acids in the diet were equally
harmful, causing an elevation of blood cholesterol/LDL levels. It is now recognized
that myristic acid (C14) is the main fatty acid responsible for rais- ing the serum
cholesterol level. This contributes to the formation of fibrous plaques and is described
as atherogenic. Both lauric acid (C12) and myristic acid also suppress the clearing
mechanism at LDL receptors, which removes LDL cholesterol from the circulation,
thus contributing to raised circulating levels. Palmitic acid (C16) has probably less
effect on cholesterol levels in the blood than originally suggested by Keys. However,
palmitic acid is the main saturated fatty acid in most diets and, therefore, has an
import- ant effect because of its prevalence. In addition, the different fatty acids
appear to have varying effects on the formation of thrombi in the blood. Myristic acid
and stearic acid (C18) are con sidered to be the most thrombogenic, together with
trans fatty acids. A reduction in thrombo- genic effects is associated with
monounsaturated fatty acids, seed oils and fish oils.
Monounsaturated fatty acids
Monounsaturated fatty acids (MUFAs), particu- larly oleic acid (18:1), were originally
believed to be neutral in their effect on blood cholesterol. However, a number of
studies have now confirmed that substitution of some of the saturated fats in the diet
by MUFAs results in a reduction of LDL cholesterol. The proposed mechanism is an
increase in LDL clearance by the liver as a result of increased receptor activity.
Polyunsaturated fatty acids
n-6 PUFAs. Fatty acids from this family have a LDL cholesterol-lowering effect,
independent of any change in saturated fat intake. The effect is achieved, it is
believed, by increasing the removal of LDL from the circulation by enhancing the
activity of the LDL receptor sites, which thus opposes the effect of the saturated fatty
acids on these receptors.
n-3 PUFAs. The n-3 fatty acids reduce VLDL levels and hence may eventually cause
a reduc- tion in LDL. The effect is linked to a more rapid clearance of VLDL rich in
n-3 PUFAs than those containing SFAs, resulting in less post-prandial lipaemia on a
n-3 PUFA-rich diet. However, the main interest in these fatty acids is associated with
their action on blood clotting, which arose from studies on Greenland Eskimos who,
despite a diet high in fat, have very low rates of heart disease.
Barasi ME. 2003. Human Nutrition A Health Perspective 2nd Edition. Hodder Arnold :
London.
Dyslipidemia Lipids are transported via lipoproteins comprised of a lipid interior
and protein shell. There are several different types of lipoproteins. These lipoproteins
vary in their protein makeup, in their lipid-to-protein ratio, and in the pro- portion of
lipid components they contain. The protein portion of the lipoprotein is called the
apolipoprotein.
Dyslipidemia refers to a lipid profile that increases the risk of atherosclerotic
development. Typically, dyslipidemia is a condi- tion in which LDL levels are
elevated and high-density lipo- protein (HDL) levels are low. (A variety of other
dyslipidemic conditions can also exist, such as the combination of normal LDL and
high triglyceride levels.) HDL particles are involved in reverse cholesterol transport,
in that they transport cholesterol from tissues and other lipoproteins to the liver. ATP
III indi- cated that serum LDL levels are the single strongest indicator of CVD risk.
Among the lipoproteins, LDL are most heavily involved in the atherosclerotic process.
Oxidation of the LDL causes this lipoprotein to be altered and can initiate damage,
starting the atherosclerotic process.
Hiperkolesterolemia dan asupan lemak
Menurut Montgomery et al (1993), hiperkolesterolemia merupakan kondisi kolesterol
dalam darah meningkat melebihi ambang normal yang ditandai dengan meningkatnya kadar
kolesterol LDL dan kolesterol total. Hiperkolesterolemia dapat terjadi faktor genetik, pola
makan tidak seimbang termasuk diet tinggi lemak jenuh atau secara sekunder yang disebabkan
oleh kelainan metabolik maupun penyakit tertentu.
Rekomedasi ADA The primary goal with respect to di- etary fat in individuals with diabetes is
to limit saturated fatty acids, trans fatty ac- ids, and cholesterol intakes so as to re- duce risk
for CVD. Saturated and trans fatty acids are the principal dietary deter- minants of plasma LDL
cholesterol. In
nondiabetic individuals, reducing satu- rated and trans fatty acids and cholesterol intakes
decreases plasma total and LDL cholesterol. Reducing saturated fatty ac- ids may also reduce
HDL cholesterol. Im- portantly, the ratio of LDL cholesterol to HDL cholesterol is not
adversely affected. Studies in individuals with diabetes dem- onstrating the effects of specific
percent- ages of dietary saturated and trans fatty acids and specific amounts of dietary cholesterol on plasma lipids are not available. Therefore, because of a lack of specific information,
it is recommended that the dietary goals for individuals with diabetes be the same as for
individuals with preex- isting CVD, since the two groups appear to have equivalent
cardiovascular risk. Thus, saturated fatty acids �7% of total energy, minimal intake of trans
fatty ac- ids, and cholesterol intake �200 mg daily are recommended.