Chapter 2: Food Categories and Composition
1. Food composition: the substances or components found in a beverage or food.
o Key nutrients:
• Large molecular substances: lipid, protein, and carbohydrates
• Small molecular substances: water, vitamins, minerals, and
o Raw foods are composed of naturally occurring substances,
o Process foods often contain specific, functional additives
The relative amount of each nutrient/substance in a food varies.
3. Cereals, grains, baked products
4. Confectionery and chocolate
5. Fruits and vegetables
6. Legumes and nuts
7. Meats, poultry, eggs, seafood
8. Milk and dairy
9. Serving size: the amount of food customarily eaten at one time.
o Serving size on food label are based on FDA established lists, and they must be
expressed in both common household and metric measures.
o Tables of food composition do not suggest a serving size, but instead provide a
measure of food, identified by weight, followed by the nutrient composition found in
o Nutrient dense => food that is capable of supplying a variety of protein, complex
carbohydrates, vitamins, and minerals without excess fat and calories.
o Ex: milk and orange juice can be considered nutrient dense, while the cola
provides only 'empty' calories.
11.Biological value (BV): amount of nitrogen derived from food protein that is used in the
body to promote growth. BV is related to the amino acid content of a protein.
12.Bioavailability: the degree to which nutrients are digested and absorbed in the body. It
is influenced by such factors as the food source, and food processing.
13.All beverages are not created equal in the amount of water they provide.
14.As the presence of dispersed substances in a beverage increases, the water content
15.Ex: orange juice and alcohol has lower water content than instant coffee.
16.Degree Brix is a measurement of the sucrose level in beverage, sucrose can undergo
inversion to produce glucose and fructose, which increase the sweetness of beverage.
This inversion process can be dependent on acidity, temperature and an enzyme
o Degree Brix/acid Ratio therefore affects the taste of beverage, and is critical in
selecting certain fruit and vegetable types to make juice. (ex: the different tastes in
brands of orange juice)
Cereals, Grains, and Baked Products 17.Cereal grains: corn, rice, wheat, barley, millet, rye, sorghum and oats.
o Composed of 3 nutritious parts: 83% endosperm + 15% bran + germ.
o Generally 75% carb, 10% protein, and <2% fat.
o The protein in cereal grains has lower biological value and bioavailability than
• Lysine + methionine can be deficient in cereal foods.
18.Leavening: the production of gases in dough that contributes to the volume achieved
during baking and the final aerated texture.
o Leavening agents: yeasts, baking soda, baking powder, and ammonium
Leavening agents produce CO2 as the specific leaving gas.
o Steam is also produced and contributes to 'oven spring'
Fruits and vegetables
19.Fruit = ripened ovary of a plant, therefore contains seeds
20.Vegetable = herbaceous plant containing an edible portion such as a leaf, shoot, root,
tuber, flower, or stem.
21.High in water content, low in protein and fat.
22.Good source of minerals,digestible carb, indigestible carb (fiber such as cellulose and
pectin), and specific vitamins.
23.Ripeness: the optimum condition of flavor, colour and texture for a particular fruit
24.Maturity: the condition of a fruit when it is picked.
25.Harvesting: the collection of fruits and vegetables at the specific time of peak quality in
terms of colour, texture and flavour in order to market them.
26.Senescence: the decline in the quality of stored, respiring fruits and vegetables that
occurs after harvesting.
Viscosity, colour, pH and titratable acidity, flavour and odor, degrees Brix.
28.Dried Fruits = dehydrated or infused fruits.
o Dehydration: removing moisture from fruits to prevent microbial and enzymatic
o Infusion: fructorse forced into a fruit piece by using heat and pressure.
Legumes and Nuts
29.Legumes: edible seeds and pods of certain flowering plants, including beans, lentils,
soybeans, and peas
30.Most legumes offer good-quality protein compared to other plants and are low in fats
31.Oilseeds: are legumes with higher fat such as soybeans, cottonseed, sesame seed,
sunflower seed and peanut seed.
32.Lipooxygenase present in the soybean is responsible for converting soybean fatty acids
to odorous compound, producing a 'beany' or 'grassy' flavour. This can be eliminated by
33.Some soyfood not only provides protein but also a phytochemical called isoflavones,
which may be effective in the prevention and treatment of cancer.
34.Tree nuts include: almonds, hazelnuts, cashew, macadamia, pecan and walnut.
35.Peanut is not a nut, but a member of the pea and bean family.
Meat and meat products
36.Meat: the edible flesh and organs of animals and fowls. 37.Meat is a source of high-quality protein and is valued for its cooked flavor and tender
o Also provides various B vitamins, Fe, Mg, and other minerals.
o Fat content of red meat ranges widely, a source of saturated and unsaturated
fatty acids and cholesterol