protein, carbohydrate, fat and fiber.pptx

protein, carbohydrate, fat and fiber.pptx

1. Organic nutrients Dr. Nabil

2. 1. Protein Protein: an energy- yielding nutrient composed of carbon, hydrogen, oxygen, and nitrogen. Differs from carbohydrates and fats because of the presence of nitrogen. The building blocks of all protein molecules are amino acids. Dr. Nabil

3. Dr. Nabil The quality of a protein is determined by its ability to provide the essential amino acids. Proteins from animal sources (eggs, meat, and fish) and one vegetable protein (soy) are all considered high-quality because they contain all of the essential amino acids in the necessary proportions.

4. Protein in the Body Protein in the Body Muscle Bone Skin Other: blood, glands, nerve tissue Dr. Nabil

5. Dr. Nabil The Function of Protein Build and maintain tissues – Needed to form the structure of muscles, organs, skin, blood, hair, nails and every other body part). Make important compounds – Body uses proteins to make hormones, and antibodies. Regulate mineral and fluid balance enzymes, some – Proteins help carry the minerals sodium and potassium from one side of cell walls to the other (keeps a balance of fluid inside and outside the cell)

6. Dr. Nabil The Function of Protein Maintain acid- base balance Maintenance of the correct level of acidity of a body fluid Proteins in the blood act as chemical buffers. Carry vital substances Used to transport lipoproteins (protein linked with fat), as well as oxygen, chromosomes, and other bundles of protein to other parts of cells Provide energy Provides the cells with the energy they need to exist If carbs and fats are lacking, the body uses protein as an energy source

7. The requirement of protein is dependent on its nutritive value, caloric intake & physiological states (growth, pregnancy, lactation) of individual. For an adult, ( RDA for protein ) 0.8-1.0 g protein/kg body weight/day is adequate. The requirement is almost double for growing children, pregnant & lactating women . Dr. Nabil

8. Quality of proteins Dr. Nabil 🞂 ​ The quality of a dietary protein is a measure of its ability to provide the essential amino acids required for tissue maintenance. 🞂 ​ Proteins from animal sources have a high quality because they contain all the essential amino acids in proportions similar to those required for synthesis of human tissue proteins. 🞂 ​ Proteins from wheat, corn, rice, and beans have a lower quality than do animal proteins.

9. Assessment of Protein Quality Dr. Nabil The quality of a protein is assessed by comparison to the “reference protein”, which is usually egg protein. Four methods of assessment of protein quality are: Chemical score or amino acid score Net protein utilization (NPU) Protein efficiency ratio (PER) Biological value (BV).

10. Other substances in food -fibers -phytochemicals -pigments -additives -alcohols

11. Fiber Dr. Nabil 🞂 ​ Dietary fiber carbohydrates consist of: Cellulose Pectin –Gums Mucilages. non- digestible carbohydrates present in food. is defined as the These Plant foods are the only sources of dietary fiber. It is found in vegetables, fruits, and grains

12. 🞂 ​ The recommended daily fiber intake (RDI) is 25 g/day for women and 38 g/day for men . Dr. Nabil