Food Chemistry

Introduction Food Chemistry: the study of producing, processing, preparing, evaluating, and using food The study of how your body uses the food you eat is nutrition Substances that are found in food and needed by the body to function, grow, repair itself and produce energy are called nutrients Your body needs over 50 different nutrients which can be divided into 6 classes: Carbohydrates Fats Proteins Vitamins Minerals Water

Major Biomolecules Carbohydrates Fats Protein

Carbohydrates Made up of C, H, and O in a 1 : 2 : 1 ratio Functions – Provides body main source of energy (quick energy) – Provide bulk – Helps the body digest fats Types – Simple –Sugars (basic bldg blocks – mono = 1) – Complex Starches and Fiber (Di = 2, Poly = many) Sources: – Sugars—honey, jam – Fiber sources—fruits, vegetables, whole grains – Starch sources— breads, cereals, pasta

Carbohydrates structure Classified as simple or complex, based on the number and structure of the sugar molecule they contain: -Monosaccharides = simple sugars -Polysaccharide = complex sugars

Fats Made up mostly of C and H with some O Functions – Provides energy – Carries fat-soluble vitamins – Protects vital organs and provides insulation – Provides essential fatty acids Types – Fatty Acids – Cholesterol Types – Fatty Acids Saturated –raises LDL Polyunsaturated- decreases LDL Monounsaturated- decreases LDL and increases HDL – Cholesterol LDL-”bad cholesterol” HDL-”good cholesterol”

Sources of Fats Cheese Butter Nuts Meats Dressings Chocolate

Fats structure

a.Saturated fats form when each carbon atom in the fatty acid chain is joined to another carbon atom by a single covalent bond Solid at room temperature (Ex: butter) b.Unsaturated fats form when there is a least one carbon-carbon double bond liquid at room temperature (ex: Olive oil) c. Polyunsaturated fats form when there are two or more carbon-carbon double bonds liquid at room temperature (ex: Corn, sesame & peanut oil)

Proteins Made up of C, H, O, and N Functions – Build and repair tissues – Help body make important substances – Regulate body processes – Supply energy Types – Complete: contains adequate amounts of all essential amino acids – Incomplete: Lacks some amino acids Sources – Meat-Complete – Milk-Complete – Eggs-Complete – Fish-Complete – Nuts-Incomplete – Legumes-Incomplete

Protein structure Proteins are polymers of amino acids

Dietary Guidelines 55 % of person’s calories should come from carbohydrates 15 % from protein 30% or less from fat

Vitamins Can be divided into two main categories Fat-soluble vitamins – dissolve in fats – can be stored in fatty tissues of the body Water-soluble vitamins – dissolve in water – are not stored in the body

Fat-Soluble Vitamins

Water-Soluble Vitamins

Minerals Minerals can also be divided into two categories: Macrominerals are needed in amounts of 100 mg or more per day. Trace elements are needed in amounts less than 100 mg per day.

Macrominerals

Trace Minerals

Excess Nutrients As with everything, too much of any one thing is not good for you and the same thing goes for nutrients. Excess energy nutrients-carbohydrates, fats, and proteins-can lead to unhealthy weight gain Excesses of some vitamins and minerals can lead to toxicity (poisoning) and other complications

Food Labels= must be on all packaged foods as of 1990 federal law

D. Nucleic Acids 1.Made up of C, H, O, N, and P 2.Uses: a. Store and transmit genetic information b. Make proteins 3.Made up of nucleotides a.5 – Carbon sugar b.Phosphate group c.Nitrogenous base 4. Example: DNA and RNA