Introduction Flashcards
When the did study of chemistry develop?
In the 1800s
What is the differentiating factor between lipids and carbohydrates/proteins?
Lipids: fat-soluble
Carbohydrates/Proteins: water-soluble
When did food science develop as a field of expertise?
In the 1970s
What is the problem with Olestra?
- Easy to abuse of since it is calorie free
- Becomes a laxative
What is Simplesse? What is it made of?
- Protein-based
- Fat substitute
What are the four principle elements found in food?
H, C, O, N
What are covalent bonds?
- Sharing one or more pairs of electrons
- Very strong, not easily broken in food
What are ionic bonds? How are they found in the body?
- Cations (+) and anions (-)
- Easy to dissolve in water since they are salts
- Always found dissolved in our bodies
What are hydrogen bonds?
- Compounds containing O or N with covalently bonded hydrogen will form a hydrogen bond with another hydrogen
- Very weak bond
What does this correspond to?
NH2-CHR-COOH
General structure of an amino acid
What does this correspond to?
CH3-(CH2)n-COOH
General structure of a fatty acid
What functional groups are responsible for making french fries taste delicious? Why do cheap restaurants have better fries?
- Aldehydes and ketones
- Restaurants that do not change their oils often have better fries
- Oils that are degraded will generate aldehydes and ketones
Which functional group smells bad?
Sulfur
What is the functional group of acids? Do they gain or lose protons?
- Carboxylic acid (COOH)
- Donate (lose) protons
What is the charge of anion? What is the charge of cation?
Anion: -
Cation: +
What is the amino group? What is ammonia? Do they gain or lose protons? Are they acidic or basic?
- NH2
- Ammonia: NH3
- Basic
- Gain protons
How would you get rid of the smell of fish on your hands?
- Lemon juice will get rid of the amines
- Acidifies the amine, which will turn it into a water-soluble material that will wash off your hands
Which functional group do alcohols contain?
Hydroxyl (-OH)
Name an example of a lipid and a vitamin that contains OH groups.
- Lipid: cholesterol
- Vitamin: retinol, calciferol
What is the functional group of the aldehyde group?
- -CHO
Aldehydes can be formed from ____________ and generally have very low _________
- lipid oxidation
- sensory thresholds
What are the three types of covalent linkages? Which compounds are they found in?
- Ester linkages (in lipids)
- Peptide linkages (in proteins)
- Glycosidic linkages (in sugars)
In food fats, fatty acids are attached to glycerol molecules through what is called an _______ linkage
ester
In proteins, individual amino acids are attached to each other through what is called a ________ linkage
peptide
How are peptide bonds formed?
- Through a condensation reaction (loss of water)
- COOH loses an OH
- NH2 loses an H
What is the difference between alpha and beta glycosidic bonds?
- Alpha: the H groups point in the same direction
- Beta: the H groups point in opposite directions
Is sucrose sweeter than glucose and fructose?
Glucose and fructose is sweeter than sucrose
What are the two main types of chemical reactions?
1) Enzymatic
2) Non-enzymatic
