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
Carbohydrates
Vitamins
divided into 6 classes:
Fats
Proteins
Minerals
Water
Major Biomolecules
• Carbohydrates
• Fats
• Protein
Carbohydrates
• Functions
Made up of C, H, and O in a 1 : 2 : 1 ratio
– 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
• Polyunsaturateddecreases LDL
• Monounsaturateddecreases 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