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Food Chemistry

Instructions:

Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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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. In genetics What is conjugation?
Linoleic Acid
Browning of freshly cut surfaces of fruits and vegetables.
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.
DNA transferred by cell to cell contact (bacterial sex).

2. What are the only phenols approved for use in the microbiological preservation of foods?
Parabens
Water
pH below positive charge; pH at no charge; pH above negative charge
Fatty Acid and Alcohol

3. Is a disaccharide
Sucrose
HPLC has higher pressure than FPLC
20 carbons and 4 double bonds
Lipase

4. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
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.
Acetoin

5. What is surimi?
.05 M HCL
Erythorbic Acid
A concentrate of microfibrillar proteins of fish muscle.
Racemic Mixture

6. What does Reichert-Meissert Number measure?
Primary butyric acid also caproic acid.
Chitin
14
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

7. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Primary butyric acid also caproic acid.
They act as catalysts - speeding the polymerization of acrylamide.
The speed of a molecule is proportional to the surrounding voltage gradient.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

8. Name a naturally occurring protein sweetener.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Thamautin
Phenophylin
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

9. If you take 20 ml of .1 M NaOH to titrate 40 mL of an HCL solution to the penolphthalein end point What is the molarity of the HCL solution?
Gliadins and Glutenins
No
.05 M HCL
Water

10. Are sorbitol and mannitol sweet?
Yes
Sodium chloride reduces foam stability and sucrose improves foam stability.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

11. In the enzyme Taq Polymerase What does Taq stand for?
They act as catalysts - speeding the polymerization of acrylamide.
Fructose
Sucrose
Thermus Aqauticus

12. How is pH defined?
Fat Oxidation
1 - 3 - 7-trimethylxanthine
Sodium bicarbonate generates CO2
Negative log of the hydrogen concentration (mol/l).

13. What does the iodine value measure and how is it measured?
Linoleic Acid
Capsaicin
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

14. What ketohexose is most significant to food chemists?
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
Pheophytin forms
Fructose
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

15. Alar is the trade name for what chemical compound?
Four
Initiation - Propagation - Termination
Daminozide
Polyphenoloxidase

16. What is the name of the degradation compound of chlorophyll?
Milk
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Phenophylin
Initiation - Propagation - Termination

17. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Orange Juice
Anthocyanins
Two aldehydes

18. Which two amino acids is the aspartame derived from?
No
Aspartic Acid and Phenylalanine
Lipid oxidation
Thermus Aqauticus

19. Name the three positively charged amino acids.
They act as catalysts - speeding the polymerization of acrylamide.
Lysine - Arginine - and Histidine
A concentrate of microfibrillar proteins of fish muscle.
Daminozide

20. What is the major color compound in tomatoes?
Lycopenes
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Whole Milk

21. Alar is the trade name for what chemical compound?
Emulsification
Tryptophan
Daminozide
Acetoin

22. What does Acid Degree Value measure and how is it measured?
Water
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Ascorbic Acid and Citric Acid
Thickener in foods

23. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Polyphenol Oxidase
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Erythorbic Acid
Oil in Water

24. What is the main class of color compounds found in raspberries?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Anthocyanins
Milk
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

25. Define molarity molality - and normality.
The speed of a molecule is proportional to the surrounding voltage gradient.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Orange Juice
Lipid oxidation

26. Name the two components that comprise the relaxing factor in muscle fibers.
Troponins and Tropomyosin
1 - 3 - 7-trimethylxanthine
20 carbons and 4 double bonds
Emulsification

27. Name 5 chelating agents used in the food industry.
Lipase
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Sodium chloride reduces foam stability and sucrose improves foam stability.

28. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Sodium chloride reduces foam stability and sucrose improves foam stability.
Water
Lipid oxidation
1 - 3 - 7-trimethylxanthine

29. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Lycopenes
No
Polyphenols

30. Name three factors useful in controlling enzyme activity.
Bright green
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
An enzyme that converts hydrogen peroxide to water plus oxygen.
Lycopenes

31. How is pH defined?
RNA transcribed to DNA
Negative log of the hydrogen concentration (mol/l).
Phenophylin
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

32. Name three non-nutritive sweeteners approved for use in USA?
No
Erythorbic Acid
Lycopenes
Acsulfame-K - Saccharin - Cyclamate - Aspartame

33. At low water activity What is the main deteriorative concern?
Lipid oxidation
Polyphenol Oxidase
Aspartic Acid and Phenylalanine
Acsulfame-K - Saccharin - Cyclamate - Aspartame

34. Name one way foam stability can be assessed.
Daminozide
Phenophylin
Polyphenoloxidase
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.

35. What are the three main steps in the autooxidation of lipids?
DNA transferred by cell to cell contact (bacterial sex).
Water
Initiation - Propagation - Termination
Pectin methylesterase & polygalacturonase

36. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Water
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Lipase
Emulsification

37. What are 3 mesomorphic structures associated with lipids in the liquid state?
Lamellar; Hexagonal I - II; Cubic
Milk
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Fatty Acid and Alcohol

38. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Emulsification
The speed of a molecule is proportional to the surrounding voltage gradient.
Four

39. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
RNA transcribed to DNA
A concentrate of microfibrillar proteins of fish muscle.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
It explodes

40. 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
Parabens
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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

41. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
.05 M HCL
Erythorbic Acid
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

42. How does HPLC differ from FPLC?
Onions ( or leeks)
D: None of the above
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
HPLC has higher pressure than FPLC

43. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Initiation - Propagation - Termination
Plasmids
Speed of Light
Carrageenan

44. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Daminozide
Lipid oxidation

45. What is the structural difference between chlorophyll and chlocophyllide?
Capsaicin
Troponins and Tropomyosin
D: None of the above
Chlocophyllide does not have a phytoltail

46. What are the four basic flavors perceived by the tongue?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Gliadins and Glutenins
Pectin Esterase - Polygalacturonase - Pectin Layase
Sweet - Salty - Sour - and Bitter

47. Name two non-enzymatic browning reactions.
.05 M HCL
Carmelization and Maillard
Two aldehydes
Water

48. What is catalase?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Blue pigment in flowers
An enzyme that converts hydrogen peroxide to water plus oxygen.
Primary-amino acid sequence. Secondary-alpha-helix - beta sheet. Tertiary-one complete protein chain with cross bonds linking it together. Quaternary-four separate protein chains assembled as one.

49. During freezing What are the two stages in the crystallization process?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Nucleation or crystal formation and crystal growth.
Gossypol (it is removed during the oil refining process)
Fat Oxidation

50. What are the three main steps in the autooxidation of lipids?
Initiation - Propagation - Termination
45% - 52% - 90%
Cis
Lycopenes