الفهرس 
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Abstract
The direct relationship between coffee drinking and coronary heart diseases in many developed countries has led to studies on coffee use as a possible coronary heart disease risk factor. In Egypt, as well as other middle east countries, coffee is consumed in a special form commonly known as Turkish coffee. The method of preparation is quite different from that commonly practiced in Europe and the United States where coffee is commonly consumed in an extracted form, the variation in the brewing procedures may modify the hyperlipidemic effect of coffee, in addition dietary fats may interact with coffee to elevate blood lipids level. The first major epidemiological study suggest a coffee- coronary disease link was the work of Paul et al (1963), this study was followed by many studies with conflicting results until the year 1985, in which many studies suggested that coffee was related to coronary disease incidence. In addition controlled experiments showed that the method of coffee brewing (regardless of its type) is the main cause in the elevation of blood lipids. Furthermore, many reports since 1987 have suggested that although coffee, tea and cola contain caffeine, the increase in serum lipids (mainly serum VLDL, LDL and cholesterol) was significantly associated with coffee consumption but not tea or cola. Therefore the simplest explanation of this iiV. ’finding is that, either coffee contains other substances rather than caffeine that might affect the serum lipid levels or both tea and cola contain other substances that balance the hypercholesterolemic effect of caffeine. Accordingly, this study was perfonned for achievement of the following aims: 1 Assessment the effect of different types of coffee on blood lipids. 2 Study the impact of heat treatment of coffee beans on blood lipids. 3 Detennination of the possible interaction between dietary fats and coffee consumption on blood lipids. F or achievements of the previously mentioned aims, several preparations of coffee were used in the present study, namely raw coffee, instant coffee and decaffeinated coffee, and to determine the effect of heat treatment, raw coffee beans were roasted according to the procedures commonly followed in Egypt. Each coffee preparations were fed ad- libitum in a semipuifid diet containing one of four types of dietary fats, corn oil, sunflower oil, palm oil or ghee to a group of 6 male albino rats weighing between 40-50 gram. In addition, the possible interaction between dietary fat, coffee consumption and dietary cholesterol was evaluated by feeding 0.5 cholesterol to animals in the above mentioned treatment. At the end of the experiment which lasted for 30 days, the animals were fasted overnight then lll. sacrificed under diethyl ether anesthesia, blood samples were collected from which sera were separated for determination of serum lipids level. After biological and statistical analysis of the results, it was found that 1 The serum cholesterol raising effect of coffee was significantly high when compared with control groups, and it was highly significant when the dietary fat was saturated than with the unsaturated ones. 11- The serum triglyceride raising effect of coffee was highly significant and was more pronounced when coffee was fed with saturated dietary fats than with unsaturated one. III- The concentration of very low density lipoprotein (VLDL) were elevated in response to feeding coffee when compared with control groups and the effect was more evident with saturated dietary fats than with the unsaturated ones. IV - The serum high density lipoprotein (HDL) were reduced when different types of coffee were fed when compared with the control groups, serum HDL level were further reduced when coffee was fed in combination with saturated rather than unsaturated dietary fats. V - The serum low density lipoprotein (LDL) were elevated when different types of coffee were fed with saturated dietary fats than with unsaturated one. VI- The type of dietary fat alone played a major role in controlling serum lipids. Corn oil and sunflower oil (which contain a large proportion of polyunsaturated fatty acids) reduced serum cholesterol, triglyceride, LDL and VLDL level, meanwhile ghee and palm oil induced a marked increase in blood lipids. Highest HDL concentration were observed in rats fed corn oil and sunflower oil in comparison to those fed ghee or palm oil. According to this results, it was found that the serum lipids raising effect of saturated dietary fat (palm oil and ghee) was more pronounced when fed with different types of coffee. And that significant increase was noted even with corn oil and sun flower oil which suggest that, the effect of added coffee is independent on the type of dietary fats. In addition, when cholesterol was added to the diet it was found that the added cholesterol has a raising effect on mean serum cholesterol and r: LDL concentration and it lowers the serum HDL. Furthermore, the data from this study suggested that all types of coffee even the decaffeinated type caused an elevating effect upon serum lipids particularly (cholesterol, T. G and LDL). Therefore, it was. concluded that, factor other than caffeine is responsible for the serum lipids raising effect of coffee, ~ince green coffee beans had the same effect as all other types of coffee. The results indicate that this factor or factors which is or/are responsible for the coffee raising. III effect of serum lipids was not fonned or destroyed during the roasting process of coffee. In summary, it would seem prudent to add coffee to the list of diet that potentiate the serum lipids elevating effect and to encourage the consumers to use unsaturated oils instead of the use of saturated fats.^leng