Saturated fat

Given their biological origins in the food chain, all foods are likely to contain compounds that are less beneficial to human health than others. In some cases (and notably in plant foods), these compounds may be detrimental as they form part of the organisms natural defense systems. In the case of milk products the trans-fats have a yet undiscovered role for humans, but like saturated fats their contribution to the human diet must be viewed in the context of the total diet. 

The reductionist approach of isolating dairy product components including calcium, CLA, and trans-fatty acids in dietary interventions trials often yields inconclusive results. It is therefore highly plausible that dairy products exert maximum health benefits when consumed in their natural form. Because individuals do not generally consume these individual dairy components in isolation, examining the effects of these foods in their whole forms should be encouraged. 

Dairy products provide a source of dietary saturated fatty acids. Generally, saturated fatty acids have been reported in the literature to increase LDL-cholesterol (Katan et al., 1994), a risk factor for CHD (Lamarche 

It is important to bear in mind when discussing the effect of dairy fat in association to heart disease that dairy products contain many different saturated fatty acids that do not exert the same biological response in terms of, for example, cholesterol levels. The saturated fatty acids in milk fat include shorter and medium chain fatty acids (2 0-10 0), lauric acid (12 0), myristic acid (14 0), palmitic acid (16 0), and stearic acid (18 0). Other fatty acids in milk fat are oleic acid (18 1) and linoleic acid (18 2n-6) as indicated in Table 1.2. 

The longer chained fatty acids, lauric, myristic, and palmitic acids are all cholesterol elevating fatty acids and it is possible that myrictic acid is the most cholesterol elevating fatty acid. Stearic acid is, however, different from the other longer chained fatty acids present in dairy fat since it may have neutral effects on cholesterol level (Katan et ah, 1994). The proportion of stearic acid in milk fat is about 11% (Lindmark-Mansson et ah, 2003). 

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The intermediate m hydrogenation formed by reaction of the unsaturated ester with the hydrogenated surface of the metal catalyst not only can proceed to the saturated fatty acid ester but also can dissociate to the original ester having a cis double bond or to its trans stereoisomer Unlike polyunsaturated vegetable oils which tend to reduce serum cholesterol levels the trans fats produced by partial hydrogenation have cholesterol raising effects similar to those of saturated fats... 

The state of knowledge in the early 1990s of the effects of fat on health lacks clarity and general agreement. There is great support for the thesis that fully saturated fats are associated with problems of atherosclerosis and arterial fatty deposit, but there is evidence that stearates, which are saturates, are only poorly utilized in human digestion. Another body of work has estabUshed a connection between unsaturated fatty acids and a better state of arterial health and lowered fat body attachment to the arterial wall (23) contrary evidence exists that highly unsaturated fats polymerize more readily and thus contribute to arterial plaque formation. 

RandomiZation/Interesterification. Transesterification occurs when a carboxyUc acid (acidolysis) or alcohol (alcoholysis) reacts with an ester to produce a different ester (20). Ester—ester interchange is also a form of transesterification. If completely unsaturated triglyceride oil (UUU) reacts with a totally saturated fat (SSS) in the presence of an active catalyst such as sodium, potassium, or sodium alkoxide, triglycerides of intermediate composition may be formed. 

The sacroplasmic proteins myoglobin and hemoglobin are responsible for much of the color in meat. Species vary tremendously in the amount of sacroplasmic proteins within skeletal muscle with catde, sheep, pigs, and poultry Hsted in declining order of sarcoplasmic protein content. Fat is also an important component of meat products. The amount of fat in a portion of meat varies depending on the species, anatomy, and state of nutrition of the animal. The properties of processed meat products are greatiy dependent on the properties of the fat included. Certain species, such as sheep, have a relatively higher proportion of saturated fat, whereas other species, such as poultry, have a relatively lower proportion of saturated fat. It is well known that the characteristic davors of meat from different species are in part determined by their fat composition. 

The beneficial effects of dietary fiber, including both soluble and iasoluble fiber, are generally recognized. Current recommendations are for daily iatakes of 20—35 g ia a balanced diet of cereal products, fmits, vegetables, and legumes. However, the specific preventive role of dietary fiber ia certaia diseases has beea difficult to estabUsh, ia part because dietary risk factors such as high saturated fat and high proteia levels are reduced as fiber levels iacrease. 

Other industrial applications of electrolysis include extraction/purification of metals from ores, electroplating, and the manufacture of certain chemicals such as sodium hydroxide. In the latter, sodium chloride solution when electrolysed is converted to sodium hydroxide to produce chlorine at the anode and hydrogen at the cathode. Both of these gaseous by-products are collected for industrial use chlorine is used in the production of bleach and PVC hydrogen is used as a fuel, to saturate fats, and to make ammonia. 

Although vegetable oils usually contain a higher proportion of nnsatnrated fatty acids than do animal oils and fats, several plant oils are actually high in saturated fats. Palm oil is low in polyunsaturated fatty acids and particularly high in (saturated) palmitic acid (whence the name palmitic). Coconut oil is particularly high in lanric and myristic acids (both saturated) and contains very few nnsatnrated fatty acids. 

Saturated fats in the diet pose a much greater health risk than unsaturated fats because they are much more likely to lead to solid deposits on blood vessels. 

We hear a lot these days about the relationships between saturated fats, cholesterol, and heart disease. What are the facts It s well established that a diet rich in saturated animal fats often leads to an increase in blood serum cholesterol, particularly in sedentary, overweight people. Conversely, a diet-lower in saturated fats and higher in polyunsaturated fats leads to a lower serum cholesterol level. Studies have shown that a serum cholesterol level greater than 240 mg/dL (a desirable value is <200 mg/dL) is correlated with an increased incidence of coronary artery disease, in which cholesterol deposits build up on the inner walls of coronary arteries, blocking the flow of blood to the heart muscles. 

Focus On... Saturated Fats, Cholesterol, and Heart Disease 1090... 

Micro-organisms are rich in protein. Microbial cells can contain as much protein as conventional foods. Bacteria can contain 60-65% (as a % of dry weight) protein whereas fungi and algae contain about 40%. In addition, microbial cells can be a rich source of fibre, unsaturated fats, minerals and vitamins. They are low in saturated fats and sodium. 

These drugs, alongwith a diet restricted in saturated fat and cholesterol, are used to treat hyperlipidemia when diet and other nonpharmacologic treatments alone have not resulted in lowered cholesterol levels. 

Unlike most saturated fats, stearic acid does not seem to increase cholesterol levels in the blood. This is because liver enzymes convert it to an unsaturated fat during digestion. 

Tristearin is a saturated fat. This means that every carbon has as many hydrogen atoms as it can hold—it is saturated with hydrogen— and there are no double bonds between any two carbons. Carbon can form four bonds. If a carbon is attached to two other carbons in a chain, the atom has two bonds left that can attach to hydrogens. 

Saturated fats are usually solid, while unsaturated fats or polyunsaturated fats (which have two or more double bonds) are usually liquid at room temperature. 

Flaky piecrusts used to contain lard, or at least butter. Solid fats are important in baking, as they separate sheets of dough into thin, independent flakes. Traditional solid fats are animal-derived saturated fats, such as lard and butter. Some vegetable fats, such as coconut and palm kernel oils, are solid, but they are more expensive than some liquid vegetable oils like corn oil, cottonseed oil, or soybean oil. These oils come from plants that are used for more than just the oil they provide. Using several different parts of the plant makes growing them more economical. 

Saturated fats like the tristearin in beef fat have higher melting points than the unsaturated fats in vegetable oils like trilin-olein or trilinolenin. 

Write the structural formula for the product of (a) the reaction of glycerol (1,2,3-trihydroxypropane) with stearic acid, CH5(CH2)16COOH, to produce a saturated fat (b) the oxidation of 4-hydroxybenzyl alcohol by sodium dichromate in an acidic organic solvent. 

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