Test your basic knowledge |

Food Chemistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Name three nonpolar polar - and charged amino acids.
Sucrose
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

2. What is the protein efficiency ratio (PER) of casein?
Aspartic Acid and Phenylalanine
Pectin methyl esterase or galacturonase
2.5
Lycopenes

3. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Oil in Water
Thamautin
Troponins and Tropomyosin
Acetoin

4. What two common compounds are used together as an antioxidative system?
Osmosis
1 - 3 - 7-trimethylxanthine
HPLC has higher pressure than FPLC
Ascorbic Acid and Citric Acid

5. 20 grams of amylose is added to 80 grams of water in a bearker; the boiling point is measured with an ordinary mercury-in-glass thermometer. What is the observed boiling point of the material in the beaker?
Ascorbic Acid and Citric Acid
Acsulfame-K - Saccharin - Cyclamate - Aspartame
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Yellow

6. What metabolic end product does the Voges-Proskauer test detect?
A concentrate of microfibrillar proteins of fish muscle.
Acetoin
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

7. Name the two components that comprise the relaxing factor in muscle fibers.
2.5
2.5
Troponins and Tropomyosin
Osmosis

8. What is acid proteolysis?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
The degree of liquid drainage or foam collapse (foam reduction) after a given time - the time for total or half-drainage (or half-reduction in volume) - or the time before drainage starts.
Degradation of protein and production of acid from sugar at the same time.
Non-protein nitrogen

9. What two enzymes degrade pectic substances?
pH 3-5
Pectin methylesterase & polygalacturonase
Acsulfame-K - Saccharin - Cyclamate - Aspartame
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

10. What is the protein efficiency ratio (PER) of casein?
2.5
20 carbons and 4 double bonds
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Prolamines

11. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Acsulfame-K - Saccharin - Cyclamate - Aspartame
They act as catalysts - speeding the polymerization of acrylamide.
Whole Milk

12. What ketohexose is most significant to food chemists?
Four
They act as catalysts - speeding the polymerization of acrylamide.
Olive Green
Fructose

13. In what food is butyric acid typically found?
Lipase
Milk
Covalent (strongest) and Hydrophobic (Weakest)
Sucrose

14. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Olive Green
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Anomeric
pH below positive charge; pH at no charge; pH above negative charge

15. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Parabens
Yellow
Olive Green
It explodes

16. What is the structural difference between chlorophyll and chlocophyllide?
20 carbons and 4 double bonds
Microorganisms are very versatile - MO's can be altered by mutations or genetic engineering to produce a greater quantity of enzyme or different enzymes - recovery of enzymes is often easy - readily available - high rate of growth and enzyme producti
Chlocophyllide does not have a phytoltail
1 - 3 - 7-trimethylxanthine

17. What are proteins which are soluble in 50-80% ethanol known as?
DNA transferred by cell to cell contact (bacterial sex).
Sodium chloride reduces foam stability and sucrose improves foam stability.
Prolamines
Speed of Light

18. Name two non-enzymatic browning reactions.
Onions ( or leeks)
Carmelization and Maillard
2.5
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

19. What is the structural difference between chlorophyll and pheophytia?
Pheophytia does not have magnesium in porphyrin ring.
Ammonia - Water - Carbon Dioxide
Initiation - Propagation - and Termination
Primary butyric acid also caproic acid.

20. During freezing What are the two stages in the crystallization process?
Pheophytin forms
Nucleation or crystal formation and crystal growth.
Anomeric
Two aldehydes

21. Alar is the trade name for what chemical compound?
Daminozide
Degradation of protein and production of acid from sugar at the same time.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Lamellar; Hexagonal I - II; Cubic

22. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
Daminozide
Linoleic Acid
Polyphenols

23. Are sorbitol and mannitol sweet?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Emulsification
Yes

24. What is the main class of color compounds found in raspberries?
Blue pigment in flowers
Monosodium Glutamate
Monosodium Glutamate
Anthocyanins

25. Match the number of carbon atoms with the common name of these saturated fatty acids. Carbon #: 4:0 10:0 - 12:0 -14:0 - 16:0 - 18:0Common Name: Myristic - Butyric - Capric - Lauric - Stearic - Palmitic
Thickener in foods
Carmelization and Maillard
HLB (hydrophilic-lipophilic balance); a low value (3-6) promotes water in oil emulsions and a high value (8-18) promotes oil in water emulsions.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

26. What does the iodine value measure and how is it measured?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Chitin
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

27. Name 5 chelating agents used in the food industry.
Thickener in foods
Acetoin
D: None of the above
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

28. What happens to chlorophyll on heating?
Polyphenoloxidase
1 - 3 - 7-trimethylxanthine
Pheophytin forms
ERH=100 x Aw

29. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Daminozide
Pectins
Phenophylin
Microorganisms are very versatile - MO's can be altered by mutations or genetic engineering to produce a greater quantity of enzyme or different enzymes - recovery of enzymes is often easy - readily available - high rate of growth and enzyme producti

30. Alar is the trade name for what chemical compound?
Primary butyric acid also caproic acid.
Pectin Esterase - Polygalacturonase - Pectin Layase
Daminozide
Phenylketonuria

31. Name three effects of protein denaturation.
Whole Milk
Negative log of the hydrogen concentration (mol/l).
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
DNA transferred by cell to cell contact (bacterial sex).

32. What is the name of the degradation compound of chlorophyll?
Pectin Esterase - Polygalacturonase - Pectin Layase
HPLC has higher pressure than FPLC
Phenophylin
Microorganisms are very versatile - MO's can be altered by mutations or genetic engineering to produce a greater quantity of enzyme or different enzymes - recovery of enzymes is often easy - readily available - high rate of growth and enzyme producti

33. Alar is the trade name for what chemical compound?
Daminozide
Thickener in foods
.05
Yellow

34. Name 3 factors influencing the consistency of commercial fats.
Cis
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Erythorbic Acid

35. How many carbon atoms and how many double bonds are there in arachidonic acid?
20 carbons and 4 double bonds
An enzyme that converts hydrogen peroxide to water plus oxygen.
Fat Oxidation
They act as catalysts - speeding the polymerization of acrylamide.

36. What two enzymes degrade pectic substances?
Pheophytia does not have magnesium in porphyrin ring.
Pectin methylesterase & polygalacturonase
Initiation - Propagation - and Termination
Aspartic Acid and Phenylalanine

37. Name a commonly used household chemical leavening agent and the gas it generates.
.05 M HCL
Troponins and Tropomyosin
Thamautin
Sodium bicarbonate generates CO2

38. Name three non-nutritive sweeteners approved for use in USA?
Anomeric
NaCl (it dissociated to a 2M solution)
Lycopenes
Acsulfame-K - Saccharin - Cyclamate - Aspartame

39. Name 3 physical agents capable of denaturing proteins.
Fat Oxidation
Pheophytin forms
Milk
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

40. What does MSG stand for?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Two aldehydes
.05
Monosodium Glutamate

41. What is the acid present in fish oil?
Bitter
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Sucrose
Arachidonic Acid

42. What are the only phenols approved for use in the microbiological preservation of foods?
No
An enzyme that converts hydrogen peroxide to water plus oxygen.
Osmosis
Parabens

43. Waxes are composed of what two basic chemical entities?
Bitter
Non-protein nitrogen
Fatty Acid (Ester linked) to Fatty Alcohol
Lipid oxidation

44. What are the only phenols approved for use in the microbiological preservation of foods?
Bitter
Four
Parabens
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

45. Name two main gluten proteins.
Fatty Acid (Ester linked) to Fatty Alcohol
Oil in Water
Bright green
Gliadins and Glutenins

46. Name three factors useful in controlling enzyme activity.
Water
Polyphenols
Primary butyric acid also caproic acid.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

47. What is Ohm's Law and What is Power Equation?
Gossypol (it is removed during the oil refining process)
Ammonia - Water - Carbon Dioxide
V=IR and P=VI or I x I x are
Gliadins and Glutenins

48. Name the strongest biochemical bond and the weakest biochemical bond.
Covalent (strongest) and Hydrophobic (Weakest)
Initiation - Propagation - and Termination
Orange Juice
Phenylketonuria

49. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
Pectin Esterase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Glycosides of anthocyanidins

50. What ketohexose is most significant to food chemists?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Fructose
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents