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. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
They are natural - nontoxic substances - generally catalyze without unwanted side-effects - active under very mild conditions of temperature and pH - active at low concentrations - rate of reaction can be controlled - can be inactivated after reactio
Two aldehydes
Carrageenan
Ascorbic Acid and Citric Acid

2. What two enzymes degrade pectic substances?
Pectin methylesterase & polygalacturonase
Yes
Polyphenol Oxidase
V=IR and P=VI or I x I x are

3. Will lipid oxidation be higher at a water activity of .05 or .5?
Tryptophan
.05
D: None of the above
Browning of freshly cut surfaces of fruits and vegetables.

4. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Monosodium Glutamate
Polyphenol Oxidase
NaCl (it dissociated to a 2M solution)
1 - 3 - 7-trimethylxanthine

5. What is the acid present in fish oil?
.05
45% - 52% - 90%
Arachidonic Acid
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.

6. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
D: None of the above
Orange Juice
Pectin methyl esterase or galacturonase
Plasmids

7. How many carbon atoms and how many double bonds are there in arachidonic acid?
20 carbons and 4 double bonds
Whole Milk
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Monosodium Glutamate

8. Name a naturally occurring protein sweetener.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Pectin Esterase
Arachidonic Acid
Thamautin

9. What two enzymes degrade pectic substances?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Anomeric
Glycosides of anthocyanidins
Pectin methylesterase & polygalacturonase

10. Name three effects of protein denaturation.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Aspartic Acid and Phenylalanine
Monosodium Glutamate

11. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Fatty Acid and Alcohol
Non-protein nitrogen
Emulsification
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

12. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Glycosides of anthocyanidins
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Acetoin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

13. Which two amino acids is the aspartame derived from?
Aspartic Acid and Phenylalanine
Fatty Acid (Ester linked) to Fatty Alcohol
Pectin methyl esterase or galacturonase
Arachidonic Acid

14. What is the chemical nature of anthocyanins?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Glycosides of anthocyanidins
Ammonia - Water - Carbon Dioxide
Yes

15. Peptide bond formation results in the formation of what secondary compound?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Water
NaCl (it dissociated to a 2M solution)
Bright green

16. Name a commonly used household chemical leavening agent and the gas it generates.
Capsaicin
Sodium bicarbonate generates CO2
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Chitin

17. 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
2.5
ERH=100 x Aw
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Daminozide

18. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Egg white proteins - the globin part of hemoglobin - bovine serum albumin - gelatin - whey proteins - casein micelles - B-casein - wheat proteins - soy proteins - and some protein hydrolyzates.
Olive Green
Troponins and Tropomyosin

19. What enzyme is most responsible for browning bananas?
Polyphenol Oxidase
.05 M HCL
Sodium bicarbonate generates CO2
Sucrose

20. Are sorbitol and mannitol sweet?
Capsaicin
Lipid oxidation
Daminozide
Yes

21. What does HLB stand for and What does a high and low HLB value indicate?
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.
Anomeric
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Lamellar; Hexagonal I - II; Cubic

22. What toxic pigment is found in cottonseed endosperm?
The speed of a molecule is proportional to the surrounding voltage gradient.
Gossypol (it is removed during the oil refining process)
Covalent (strongest) and Hydrophobic (Weakest)
Polyphenoloxidase

23. What is the major color compound in tomatoes?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Yes
Phenophylin
Lycopenes

24. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Gossypol (it is removed during the oil refining process)
Fat Oxidation
Pheophytin forms

25. What is the main class of color compounds found in raspberries?
No
Cis
Anthocyanins
Aspartic Acid and Phenylalanine

26. What are colloids that are stabilized by a layer of solvation called?
Fatty Acid (Ester linked) to Fatty Alcohol
Pectin methyl esterase or galacturonase
Emulsoids
Speed of Light

27. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
They act as catalysts - speeding the polymerization of acrylamide.
20 carbons and 4 double bonds
.05 M HCL
Pheophytin forms

28. What is the name of the degradation compound of chlorophyll?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Yes
Phenophylin
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

29. What toxic pigment is found in cottonseed endosperm?
Chlocophyllide does not have a phytoltail
Arachidonic Acid
Gossypol (it is removed during the oil refining process)
No

30. Name 5 chelating agents used in the food industry.
45% - 52% - 90%
Ammonia - Water - Carbon Dioxide
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

31. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Two aldehydes
Pectin methyl esterase or galacturonase
Pectin methylesterase & polygalacturonase
Polyphenol Oxidase

32. Name the three positively charged amino acids.
Plasmids
D: None of the above
Lysine - Arginine - and Histidine
Fatty Acid and Alcohol

33. Which of the following examples of browning is enzymatic in nature? 1. Browning of sugars as a result of heating 2. Browning of freshly cut surfaces of fruits and vegetables 3. Browning of bread during toasting 4. Browning of potato chips
Browning of freshly cut surfaces of fruits and vegetables.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Polyphenoloxidase
Two aldehydes

34. What is the main class of color compounds found in raspberries?
Anthocyanins
Initiation - Propagation - Termination
Gossypol (it is removed during the oil refining process)
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

35. What is a polymorphism?
Olive Green
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.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Orange Juice

36. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Lysine - Arginine - and Histidine
Carrageenan
Yellow
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

37. Which two amino acids is the aspartame derived from?
Aspartic Acid and Phenylalanine
No
Troponins and Tropomyosin
They act as catalysts - speeding the polymerization of acrylamide.

38. What is surimi?
Glycosides of anthocyanidins
A concentrate of microfibrillar proteins of fish muscle.
Fat Oxidation
Bright green

39. How do sodium chloride and sucrose affect foam stability?
Emulsification
Sodium chloride reduces foam stability and sucrose improves foam stability.
Chitin
Lysine - Arginine - and Histidine

40. Which of the following examples of browning is enzymatic in nature? 1. Browning of sugars as a result of heating 2. Browning of freshly cut surfaces of fruits and vegetables 3. Browning of bread during toasting 4. Browning of potato chips
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
14
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Browning of freshly cut surfaces of fruits and vegetables.

41. Alar is the trade name for what chemical compound?
Gliadins and Glutenins
Daminozide
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

42. Name two main gluten proteins.
Daminozide
Non-protein nitrogen
Gliadins and Glutenins
Arachidonic Acid

43. At what pH is benzoic acid most effective?
Yellow
Chlocophyllide does not have a phytoltail
pH 3-5
Polyphenols

44. What effect would the addition of sodium bicarbonate have to chocolate?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Browning of freshly cut surfaces of fruits and vegetables.
DNA transferred by cell to cell contact (bacterial sex).
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

45. In what food is butyric acid typically found?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
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.
Milk
Thickener in foods

46. What are two common reducing agents that break disulfide bonds in proteins?
V=IR and P=VI or I x I x are
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
They are natural - nontoxic substances - generally catalyze without unwanted side-effects - active under very mild conditions of temperature and pH - active at low concentrations - rate of reaction can be controlled - can be inactivated after reactio
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

47. Name two reasons why fats are hydrogenated.
NaCl (it dissociated to a 2M solution)
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Anthocyanins
Nucleation or crystal formation and crystal growth.

48. Name a commonly used household chemical leavening agent and the gas it generates.
20 carbons and 4 double bonds
Speed of Light
Sodium bicarbonate generates CO2
Orange Juice

49. What pigment was first designated as anthocyanins?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Blue pigment in flowers
45% - 52% - 90%
Polyphenols

50. What is the name given to a mixture of equal parts of Darel Lisomers?
Daminozide
Ammonia - Water - Carbon Dioxide
Polyphenols
Racemic Mixture