classification ofFood and food composition.ppt
- 2. Introduction Classes Composition Sudan food values Contents
- 3. Introduction Food is substance consumed to provide nutritional support for the body. It is usually of plant or animals origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, and minerals. The substance is ingested by an organism and assimilated by the organism's cells to produce energy, maintain life, or stimulate growth.
- 4. Foods can be classified in the following categories. each has its own characteristics: Cereals and starchy roots. pulses, legumes, seeds and nuts. Meat. Milk and eggs. Fats and oils.
- 5. Vegetables and fruit. Sugar and syrups. Beverages.
- 6. The main cereals consumed by man are: wheat, rice ,grain , and maize. Cereals are a good source of carbohydrate (contains starch from 70-80 % of its weight). Cereals are an important source of proteins in the poorer parts of the world. The grain contains 7-12% of its dry weight as protein.
- 7. Most cereal proteins are deficient in one or more amino acids (wheat and sorghum protein are deficient in lysine and maize protein deficient in tryptophan). Cereals also are a good source of minerals and B group of vitamins.
- 9. Wheat
- 10. Starchy roots, e.g. cassava, yams and potatoes, are mainly composed of starch. They used in many parts of the world as a major source of CHO instead of cereals. Raw potatoes contains about 1-8% protein, and the new potatoes contains ascorbic acid.
- 11. Cassava
- 12. Yams
- 13. Different types of potato
- 14. Many varieties of seeds are eaten in various parts of world. The main nutrient ingredients of these are starch (60% of dry weight) and a high content of protein (about 20% of dry weight). If eaten with a cereal food like bread, chapati, kisra, or porridge (asida) or any other form of local cereal food, these pulses supply the deficient amino acids of the cereal protein.
- 15. Ground nuts are pulses and have a high protein content (26%) and high fat content (44%). And they are also very rich in iron and niacin. Sesame contain about 50% fat, 20% carbohydrates, 20% protein. Sesame has a good content of sulphur-containing amino acids, and also is a rich source of calcium (1200 mg/100g).
- 16. Soya beans are rich in protein 38% CHO 20% fat 18% and already an ingredient of many food preparations in the developed parts of the world.
- 17. Lupine (arabic: turmos or termis) is rich in protein and phosphorus (545 mg/100g), and the calcium content is (90 mg/100g). It is common native practice to advise a person who has sustained a fracture to eat lupine.
- 18. Beef, lamb, pork and poultry are the main meat products consumed by the various people of the world to various extents depending on availability, local culture and religious prohibitions. The nutritional importance of meat lies: - First in the rich protein content. - Second the high quality of this protein: I.e. containing all essential amino acids.. High biological value protein.
- 21. Fish: Fish, like meat, contains protein of high biological value. Fish oils contain long-chain ω3-polyunsaturated fatty acids, mainly eicosapentaenoic acid (20 c) and docosahexaenoic acid (22 c). There is very little carbohydrate in fish and quite small amounts of cholesterol. It is not usually a good source of fat-soluble vitamins, particularly those with antioxidant activity but whole body fish like sardines provide vitamin D.
- 22. Human milk is the first food a baby gets. It provides all the essential ingredients of a balanced diet except iron and vitamin C. Up to the fourth month, babies may depend entirely on milk without risk of nutritional deficient. Cow’s milk is about 88% water and 3% protein. The two main proteins are casein (comprises about 82% of the total protein) and whey proteins which include lactalbumin and lactoglobulin.
- 23. Milk carries B group vitamins, particularly riboflavin and vitamin B12, and the fat soluble vitamins A and D. • The energy content of milk varies mainly with its fat content. • An approximately value is 270 kJ (65kcal)/100 ml. • It is one of riches food of calcium. • Cheese: the popular milk products, cheese is about ten times the concentration of milk and provides a good storage form for the protein, fat and calcium content of milk.
- 24. Comparison of human milk with milk from other sources: Human cow goat ewe camel Protein (casein) (g) 1.5 3.5 3.7 6.5 3.7 Fat (g) 4.5 3.5 4.8 6.9 4.2 CHO (lactatose) (g) 6.8 5.0 4.5 4.9 4.1 Iron (mg) 0.7 0.1 0.2 - - Phosphorus (mg) 14 91 129 - - Calcium (mg) 34 120 150 - -
- 26. Eggs: Eggs are good source high quality protein , calcium, vitamins A and B12 and high cholesterol content of the yolk. A medium size egg (60g) will provide the following:
- 28. Ostrich egg (right), compared to chicken egg (lower left) and quail eggs (upper left).
- 29. Fats & Oils: The main sources of dietary fat are meats, dairy products, and vegetable oils. Some fats can occur in solid form when kept at low temperature (saturated lipids). Oils, however, do not solidify (composed unsaturated lipids). Fats are a good source of energy .
- 30. Vegetables comprise any plant part, other than fruit which is used as food. They include roots and tubers such as potatoes, taroالقلقاس , carrots, and yams, lettuce الخس and cabbage ملفوف, Some fungi (e.g.mushrooms) are also consumed as vegetables.
- 31. Green leafy vegetables have a very high water content and are exceptionally low in energy while relatively high in micronutrients. Some vegetables are rich in micronutrients: potatoes are a major source of vitamin C, carrots are exceptionally high in β-carotene, and spinach is rich in folic acid and iron .
- 33. Some fruit contain good supplies of calcium and phosphorus, but is a poor source of iron. This is because they are low in energy, fat and sodium and make valuable contributions to the intakes of vitamin C, carotenoids, folate and dietary fibre. Numerous epidemiological studies have shown that people who eat above average amounts of fruit and vegetables have below average rates of heart disease and cancer.
- 35. Cane sugar is a relatively new addition to the human diet. Sugar contains sucrose which gives about 4 kcal/g. Syrup is also made of sugar.
- 36. • Tea and coffee is widely consumed beverages. • The main ingredient of these drinks is caffeine. • The usual dose in a tea cup is about 60 mg and in a coffee is 90 mg. • Cola drinks may contain 50 – 200 mg of caffeine/ l. • Alcohol containing drinks provide 7 kcal/g of alcohol. • Alcoholic drinks can contain 3-5% beers, 10-15% in wines, 20- 25% in sherries and up 45-50% spirits.
- 37. Chemical composition of foods
- 38. Water: The water content of a food item is obtained by means of weighting the sample before and after drying by heat. Some food may contain volatile substances and therefore heating will not be suitable for estimating the moisture content.
- 39. Energy values: Energy values are obtained by two method: • Directly, the energy content of a sample can be measured using a bomb calorimeter . • In this method, a measured amount of the food is burnt in oxygen inside a heavy closed container. • The heat generated is measured and converted into energy. • Indirectly the energy content of foods is calculated from the protein, fat and carbohydrates.
- 40. The proteins: • Are usually calculated from the total nitrogen content of the food item multiplied by a factor of 6.25/g of nitrogen.
- 41. The fat: The fat content of food is obtained by extraction using different methods. Carbohydrate values: Carbohydrate values include sugars and starches. This value is calculated from results of direct analysis for sugars and starches.
- 43. Food and description Food energy (cal) Moistu re (g) Carbo hydra tes (g)’ Prote ins (g) Fat (g) Crud e fiber (g) Ash (g) Calciu m (mg)’ Iron (mg) Ph osp hor us (m g) Meat mutton cooked 213 57.6 6.9 25.4 8.6 0.0 1.5 Meat mutton fried 292 52.0 0.0 26.2 20. 0 0.0 1.8 Mulah rigila 81 79.2 12.0 3.9 2.4 0.6 1.9 100 4.3 40 Ful masri boiled oil and salt (broad beans) 74 77.7 9.8 9.0 0.3 2.4 0.8 59 1.5 65 Kisra with various type 180 50.1 42.5 5.8 0.3 0.4 0.9 20 1.0 134 Macaroni suksukania unenriched not cooked 365 10.5 76.1 10.8 0.9 1.3 0.4 58 0.5 11
- 44. Sukkar MY. Human Nutrition for Medical Studies & Allied Health Sciences. London; 1985. p.13-18. Essentials of Human Nutrition (2002) Mann J. ; p. 383-403.