1. What is food chemistry?
The study of the chemicals inside common foods and how they react.

2. WHy study food chemistry
To understand the major components of foods:
Lipids
Protein
Carbohydrates
And the chemical changes of food composition which occur during the preparation of food
So we can live healthy lives

3. What is Your food made out of?
Basic food chemistry deals with the three primary components in food:
Carbohydrates
Lipids
proteins

4. Scientists study food chemistry
To develop a successful food product one needs a basic understanding on how ingredients work chemically and how they interact with each other
Shelf stability
Appearance
Texture
Taste
Nutrition

5. Major components of food

6. Carbohydrates
Make up a group of chemical compounds found in plant and animal cells.
Contain the elements C, H and O having the general formula (CH2O)n
Since this formula is essentially a combination of carbon and water these materials are called “hydrates of carbon or carbohydrates”.

7. Carbohydrates
Carbohydrates are the primary product of plant photosynthesis, and are consumed as fuel by plants and animals.
Food carbohydrates include the simple carbohydrates (sugars) and complex carbohydrates (starches and fiber).

8. Lipids (fats) Lipids include: Fats Oils Waxes Cholesterol
In the body, fat serves as a source of energy, a thermal insulator, and a cushion around organs; and it is an important component of the cell.

9. Lipids (fats)
In most instances, fats are from animal products – meats, milk products, eggs, and seafood
Oils are from plants – nuts, olives, and seeds.
We use lipids for flavor, to cook foods, and to improve the texture of foods.

10. Proteins Proteins are important components of food
Every cell requires protein for structure and function
Proteins are complex polymers composed of amino acids.

11. Proteins There are 20 amino acids found in the body
Eight of these are essential for adults & children
Nine are essential for infants,
Essential means that we cannot synthesize them in large enough quantities for growth and repair of our bodies, and therefore, they must be included in our diet

12. Proteins
Proteins consist of long chains of amino acids that form into three-dimensional structures, their native state.

13. Proteins
When you change the native state of the protein, you change the three-dimensional structure, which is referred to as denaturation.
Some factors that cause denaturation include:
Heating
Acid

14. Example – Hot dog Fat Protein Carbohydrates Additives Water
-Nutritional
Mouth feel
Appearance
Lipid oxidation
Saturated vs.
unsaturated fat?
Protein
Nutritional
Functional properties
Water binding
Emulsification
Texture
Animal vs. vegetable
proteins?
Carbohydrates
Functional properties
Starch
Additives
Salt
Texture
Antimicrobial
Flavor
Coloring agents
Antimicrobials
Antioxidants
Buffers
Water
How much?
Where is it
bound?
Processing and storage
Loss of function
Loss of nutrients
Hazard development

15. What happens to food when you cook it? Are they all chemical changes?

16. Cooking =Chemical and physical changes
new substances are made
the texture and taste changes
the process is irreversible
an energy change occurs
color changes

17. Cooking carbohydrates
Starches consist of long chains of glucose (sugar) molecules
Cooking provides energy (heat) to break the long chains into individual glucose (sugar) molecules
The heat then aids in the breaking down of sugar into Carbon and water

18. Cooking Fats
Liquify but do not break down during cooking as they can withstand very high temperatures.

19. Cooking Proteins
The protein molecules change shape as a result of the heat energy they absorb.
This is called denaturing and it is permanent. Denaturing causes changes in the appearance and texture of the meat and eggs when they are cooked.
Changes texture and taste of the food

20. Cooking Prteins

22. Additional changes when cooking proteins
Maillard Reaction: Meat turns brown when cooked
Meat is red due to the protein myoglobin (not due to blood)
Cooking oxidized/reacted the Iron in myoglobin turning it brown

23. Additional changes when cooking proteins
White meat has very low levels of myoglobin so it doesn’t appear red and doesn’t turn brown when cooked.

24. Additional changes when cooking proteins
Nitrates are added to meats to keep the red appearance.

25. Additional cooking substances
Baking Powder: Baking powder is used for baking cakes. It contains sodium hydrogen carbonate, which breaks down when heated to form carbon dioxide gas. The carbon dioxide helps to make the cake mixture rise, so that the cakes are light and fluffy.

26. Additional cooking substances
Here is the word equation for the reaction:

27. Genetically modified organisms
In genetic engineering, scientists splice genetic material from plants, animals, or bacteria and insert this genetic material into the DNA of other organisms.
These new organisms are called genetically modified organisms (GMOs).

29. Food calories The amount of energy stored in food
1 food Calorie is equal to 1 kCal or 1,ooo calories
The formula: q =mcΔT
q= heat/energy (calories)
m= mass (g)
c= specific heat of water (1 cal/g℃)
ΔT= change in temperature (℃)

30. Example: If the mass of the water is 150 grams and
the change in temperature of the water
as as Doritos is burned is 50 celsius how many
calories is the the Doritos?
q =mcΔT
q =(150g) x (1 cal/g℃) x (60C) = 7,500 calories
7,500/1000 = 7.5 food calories in 1 Doritos