This document summarizes the key chemical components of food: - Food is made up of chemicals organized into cellular structures. The six main categories are carbohydrates, fats, proteins, vitamins, minerals, and water. - Carbohydrates include sugars (simple) and polysaccharides (complex) such as starch. Fats are characterized by their greasy feel. Proteins are made of amino acids and include albumins, globulins, and enzymes. - Vitamins and minerals, though only needed in small amounts, are essential for health. Water is the most abundant element and acts as a solvent.

1. Chemical Structure of
Food
HRM 408

2. FOOD

3. FOOD
• Is a mixture of Chemicals in well-ordered
system of cellular structures.
• Any food item can be separated into chemically
identifiable substances.

4. Chemical
Structures in
Food
Carbohydrates
Fats
Proteins
Vitamins
Minerals
Water
6 categories

5. WATER

6. WATER
• Water is present in all food items
• The most aboundant of all elements in its
natural state
• Water is a biological solvent
• Boiling poin 100°C

7. Properties Of Water
H2O
2 Hydrogen atoms + 1 oxygen atom
Atoms are aranged in non linear,
three-dimentional structure

8. Water Activity
• Water activity or (aw) is the partial vapor pressure of water in a
substance divided by the standard state partial vapor pressure
of water.
• aw= water activity
• P= partial pressure water in the food
• P0=partial pressure of water at the same temperature

9. Carbohydrates

10. Carbohydrates
•(CH2O)n
•Hydrates of Carbon
•Energy source

11. Carbohydrates
• Subdivided into:
Sugars (simple sugars)
Polysaccharides (complex)

12. Sugar
Classified as:
•Monosaccharides
•Disaccharides
•Trisaccharides
Most common sugars
• Glucose(grape sugar)
• Fuctose(fruit sugar)
• Sucrose(sugar cane)

13. Oligosaccharides
•Means several units of sugar
•Trisaccharides like raffinose is usualy
classified as Oligosaccharides

15. Polysaccharides
• A long chain of glucose molecules forms an
important polysaccharide starch
Starch – has many uses in cookery
– contriutes significantly to the supply of
calories in diets

16. Polysaccharides
Starch is chief food reserve of plants and is converted into
sugar(by plant)
 Cellulose – chief structural carbohydrates of plants
 Pectin – another complex carbohydrate present in fruits
Fiber – term applied to polysaccharides that cannot be digested
in human digestive tract

17. Classification of Polysaccharides and Food
Sources
Polysaccharides
• A. Digestible
1.Starch
2.Dextrins
3.Glycogen(animal starch)
• B. Partially Digestible
1.Galactogens
2.Inulin
3.Mannosans
• C. Indigestible
1.Cellulose(vegtable stalks)
2.Hemicellulose (a. agar-agar, b. pectin)
3Lignin
Food Sources
Cereal(grain,rice,corn),unripe fruits and vegtables
Toasted bread and intermidiate
Pectins,Snail,agar-agar
Mushroom,onion,garlic
Legumes
Skins of fruits and seed covering
Slightly unripe fruits,seeweeds
Woody parts of plant

18. FATS

19. Fats
Characterize by their appearance and greesy
feels and inability to mix with water.

20. Natural
Oils •Animal Fat
•Marine Fat
•Vegtable Fat (most
aboundant food fat)
Classified accourding
to origin:

21. Proteins and
Amino Acids

22. Proteins
•Are Organic Substances
•The building units of Proteins are amino
acids
•1 protein contains 500 or more units of
amino acids

23. Proteins
• Denaturation is a term applied to any alteration to
original properties of protein but not in amino acid
sequence
• Denaturation of meat usually occurs 57 – 75°C

24. Classification of Protein and Food Sources
Protein
• I. Simple proteins
A. Albumins
B. Globulins
C. Glutelins
D. Prolamines
• II.Conjugated Proteins
A. Nucleoproteins
B. Mucoproteins
C. Chromoproteins
D. Phosphoproteins
E. Metalloproteins
Sources
• Legumes in peas,albumin in eggwhites
• Serum globulin,myosin in mucle, edestin in wheat
• Glutenin in wheat, oryzenin in rice
• Protein of nails,bones connective tissues as collagen
• Ribonucleuprotein in cell cytoplasm
• Ovomucoid in egg white, osseomucoid in bones
• Hemoglobin, Flavoprotein
• Casein in milk and ovovitellin in eggyolk
• Hemoglobin and hemocuprein

25. Classification of Protein and Food Sources
• III. Derived Proteins
A. Protein, metaproteins and
coagulated proteins
B. Proteoses, peptones and peptides
• Cooked protein foods as in fried
eggs,cooked meats,fish and legumes
chees and custard
• Intermediate products of protein
digestion or hydrolysis

26. •Enzymes- protein molecules
syntesized by living organism
for specific action as biological catalysts.

27. Useful application of enzymes in food:
1. Meat tenderizer –bromelin from pineapple and papain and effective
tenderizers of mussle meat.
2. Invertase –sucrose inversion is facilitated by adding enzyme
invertasefor certain confections like the soft of chocolate centers of
candies
3. Anylases –The splitting of starch in flour during bread making by
the presence pf amylases yields fermentable sugars to be acted upon
by yeast

28. Useful application of enzymes in food:
4. Pectinases –Ripening of fruits
5. Microbial enzymes bring about
fermentation and proteolysis as in patis and
bagoong, vinegar and wine making, and cheese
ripening.

29. Vitamins

30. Vitamins
• Complex organic compounds that are required in
the diet in very small amount but are vital for
maintenance of health
• Absence of these compounds cause defieciency
diseases

31. • The fat-solabel vitamins are: Retinol: (vitaminA),
Cholecalciferol(vitamin D), Tocopherol (vitamin E), and
Phyloquine (vitamine K)
• The water-soluble vitamins are: Ascorbic asid(vitamin
C), Thiamin(vitamin B1), Riboflavin(vitamin B2),
Pyridoxide(vitamine B6),Niacin Pantothenic acid,
Cobalamines(vitamin B12), Folic acid,Biotin, Choline,
Inositol.

32. Minerals and Trace
Elements

33. Minerals and Trace elements
• Are inorganic substances that may be or may not be in
combination with organic constituents
• Classified into two categories:
Those that need more than 0.005 percent of body weight and
those who don’t
The latter are called Traced elements