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.