What is nutrition The word 'Nutrition" comes from a Latin word which means to 'nourish" or to "to feed". Nutrition covers many areas including: the science of food why people/animal choose certain foods what foods are made of the nutrients in foods how the body uses food food digestion food functions

Food composition What are foods made of? Carbohydrates Proteins Fats Vitamins Minerals Water

Carbohydrates Carbon, hydrogen and oxygen Ratio H:O = 2:1 similar to water Acetic acid, lactic acid, deoxyribose, rhamnose Polyhydroxy aldehide or polyhydroxy keton Primary function: – Source of energy Located in plant and animal tissues – Simple carbohydrate- starches (grains) – Complex carbohydrate- cellulose (component of cell walls)

SOURCE OF CALORY – 55-60% of caloric intake – 1 gram yields 4 calories Carbohydrates

Simple carbohydrates 1.Monosaccharides –Glucose –Fructose –Galactose 2.Disaccharides –Sucrose (Glucose + fructose)Cane –Maltose (Glucose + Glucose)Starches –Lactose (Glucose + Galactose)Milk

Carbohydrates Complex carbohydrates 1.Cellulose Ruminants require microbial fermentation to break down complex carbohydrates

Carbohydrates Carbohydrates come from plant foods. They are the cheapest and most plentiful of all nutrients. Foods, which contain carbohydrates, are called energy foods. Carbohydrates are classified into three groups: Sugar Starch fiber

Sources of carbohydrates Sugars are found in honey, fruit (both fresh and dried) soft drinks, milk and sugar. Starches are found in cereals, pasta, flour, bread, potatoes, root and pulse vegetables. Fibers are found in fruits, vegetables and whole wheat bread.

Functions of carbohydrates Carbohydrates provides the body with heat and energy. Fiber helps the movement of food through the intestine. Fiber rich and starchy foods provide a "full feeling". Carbohydrate deficiency: Carbohydrate deficiency diseases rarely occur, as carbohydrate is present in a wide variety of foods. Starting material for synthesis of other type of compound e.g. fatty acid and certain amino acid Structure of: glycolipid, glycoprotein, nucleic acid

SUGAR MONO- SACCHARIDES TRIOSESGLYCERALDEHYDE DIHYDROXYACETON TETROSESERYTHROSE PENTOSESARABINOSE XYLOSE RIBULOSE RIBOSE HEXOSESGLUCOSE GALACTOSE MANNOSE FRUCTOSE HEPTOSESSEDUHEPTULOSA OLIGO- SACCHARIDES DISACCHARIDESSUCROSE LACTOSE MALTOSE CELLOBIOSE TRISACCHARIDESRAFFINOSE KESTOSE TETRA- SACCHARIDES STACHYOSE

NON SUGAR POLY- SACCHARIDES HOMOGLYCANS ARABINANS XYLANS GLUCANSSTARCH DEXTRINS GLYCOGEN CELLULOSE FRUCTANSINULIN LEVAN GALACTANS MANNANS GLUCOSAMINES HETEROGLYCANS PECTIN HEMICELLULOSES GUMS ACIDIC MUCILAGES HYALURONIC ACID CHONDROITIN COMPLEX CARBOHYDRATES GLYCOLIPIDS GLYCOPROTEINS

FRACTIONCOMPONENTSNUTRITIONAL AVAILABLE RUMINANTNONRUMINANT CELL CONTENTLIPIDVIRTUALLY COMPLETE HIGHLY AVAILABLE SUGAR-,,- STARCH-,,- NPN-,,- SOLUBLE PROTEIN-,,- PEPTIN-,,- CELL WALL 1.ADSHEMICELLULOSEPARTIALVERY LOW 1.ADFCELLULOSE-,,- LIGNININDIGESTIBLE LIGNIFIED NITROGEN INDIGESTIBLE HEAT DAMAGED PROTEIN INDIGESTIBLE SILICAINDIGESTIBLE