food chemistry
DESCRIPTION
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 - PowerPoint PPT PresentationTRANSCRIPT
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
FatsProteins
VitaminsMineralsWater
Major Biomolecules
• Carbohydrates
• Fats
• Protein
CarbohydratesMade 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 Acids1. Made up of C, H, O, N, and P2. Uses:
a. Store and transmit genetic informationb. Make proteins
3. Made up of nucleotidesa. 5 – Carbon sugarb. Phosphate groupc. Nitrogenous base
4. Example: DNA and RNA