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Food Chemistry

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Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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1. What does MSG stand for?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Monosodium Glutamate
Pectin Esterase - Polygalacturonase - Pectin Layase
Whole Milk

2. What are two common reducing agents that break disulfide bonds in proteins?
Olive Green
pH 3-5
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Monosodium Glutamate

3. Name 3 factors influencing the consistency of commercial fats.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Troponins and Tropomyosin
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

4. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Erythorbic Acid
Oil in Water
Phenylketonuria
Ammonia - Water - Carbon Dioxide

5. What are the four basic flavors perceived by the tongue?
pH 3-5
The speed of a molecule is proportional to the surrounding voltage gradient.
Sweet - Salty - Sour - and Bitter
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

6. When heated ammonium bicarbonate decomposes to form what end products?
Ascorbic Acid and Citric Acid
Ammonia - Water - Carbon Dioxide
Pectin methylesterase & polygalacturonase
Pectins

7. What is the acid present in fish oil?
Ammonia - Water - Carbon Dioxide
Arachidonic Acid
Polyphenols
Thermus Aqauticus

8. What does the saponification value measure and how is it measured?
Lamellar; Hexagonal I - II; Cubic
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Anthocyanins

9. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Polyphenoloxidase
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Milk
Browning of freshly cut surfaces of fruits and vegetables.

10. What is the Peroxide Value a measure of?
HPLC has higher pressure than FPLC
Fat Oxidation
Non-protein nitrogen
Yes

11. What is a polymorphism?
Daminozide
Chitin
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

12. What is the geometric configuration of double bonds in most natural fatty acids?
Primary butyric acid also caproic acid.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
.05
Cis

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

14. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
.05
Bright green
Chitin
Tryptophan

15. What is acid proteolysis?
20 carbons and 4 double bonds
Degradation of protein and production of acid from sugar at the same time.
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).

16. Alar is the trade name for what chemical compound?
No
Chitin
Daminozide
Carmelization and Maillard

17. What does the iodine value measure and how is it measured?
Anomeric
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Parabens

18. Contains the lowest content of water
Yes
It explodes
Whole Milk
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

19. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Sweet - Salty - Sour - and Bitter
Pectins

20. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
pH below positive charge; pH at no charge; pH above negative charge
Sweet - Salty - Sour - and Bitter
Yes
Chitin

21. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
A concentrate of microfibrillar proteins of fish muscle.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

22. 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?
HPLC has higher pressure than FPLC
Olive Green
.05 M HCL
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

23. At low water activity What is the main deteriorative concern?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Lipid oxidation
An enzyme that converts hydrogen peroxide to water plus oxygen.
Polyphenoloxidase

24. At what pH is benzoic acid most effective?
Emulsoids
pH 3-5
Pheophytia does not have magnesium in porphyrin ring.
Lipase

25. Peptide bond formation results in the formation of what secondary compound?
Emulsoids
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Water
They act as catalysts - speeding the polymerization of acrylamide.

26. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Pectins
Polyphenoloxidase
Lamellar; Hexagonal I - II; Cubic
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

27. Contains the lowest content of water
D: None of the above
Whole Milk
Water
Ascorbic Acid and Citric Acid

28. What compounds oxidize to form brown color in fruits and vegetables?
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)
Polyphenols
Phenylketonuria

29. Alar is the trade name for what chemical compound?
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.
Anomeric
Daminozide
Linoleic Acid

30. What charge will a protein have when the pH of its solution is below at - and above its pKa?
The speed of a molecule is proportional to the surrounding voltage gradient.
A concentrate of microfibrillar proteins of fish muscle.
Daminozide
pH below positive charge; pH at no charge; pH above negative charge

31. Peptide bond formation results in the formation of what secondary compound?
Water
Two aldehydes
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
1 - 3 - 7-trimethylxanthine

32. How can a molecular weight of protein - DNA - and RNA be determined?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
HPLC has higher pressure than FPLC
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Sodium chloride reduces foam stability and sucrose improves foam stability.

33. What is the enzyme responsible for browning in apples and lettuce?
NaCl (it dissociated to a 2M solution)
Polyphenol Oxidase
Lysine - Arginine - and Histidine
14

34. What effect would the addition of sodium bicarbonate have to chocolate?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Carmelization and Maillard
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).

35. What metabolic end product does the Voges-Proskauer test detect?
Thamautin
Bright green
Acetoin
Gliadins and Glutenins

36. Alar is the trade name for what chemical compound?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Daminozide
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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. What is catalase?
Carrageenan
An enzyme that converts hydrogen peroxide to water plus oxygen.
Capsaicin
Sodium bicarbonate generates CO2

38. What is the chemical nature of anthocyanins?
Bright green
RNA transcribed to DNA
Linoleic Acid
Glycosides of anthocyanidins

39. What are colloids that are stabilized by a layer of solvation called?
Non-protein nitrogen
Negative log of the hydrogen concentration (mol/l).
Emulsoids
NaCl (it dissociated to a 2M solution)

40. What is the structural difference between chlorophyll and pheophytia?
HPLC has higher pressure than FPLC
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Troponins and Tropomyosin
Pheophytia does not have magnesium in porphyrin ring.

41. What two enzymes degrade pectic substances?
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.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Pectin methylesterase & polygalacturonase
Monosodium Glutamate

42. What is the name given to a mixture of equal parts of Darel Lisomers?
Racemic Mixture
Lamellar; Hexagonal I - II; Cubic
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
20 carbons and 4 double bonds

43. What are 3 mesomorphic structures associated with lipids in the liquid state?
Fructose
Four
Prolamines
Lamellar; Hexagonal I - II; Cubic

44. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
NaCl (it dissociated to a 2M solution)
Polyphenol Oxidase
Carrageenan
Osmosis

45. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Yellow
Gossypol (it is removed during the oil refining process)
Acetoin

46. How many carbon atoms are there in the fatty acid myristic acid?
Pheophytin forms
Monosodium Glutamate
14
ERH=100 x Aw

47. What does the 'c' stand for in the equation E=mc2?
Non-protein nitrogen
Speed of Light
They act as catalysts - speeding the polymerization of acrylamide.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

48. What ketohexose is most significant to food chemists?
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.
DNA transferred by cell to cell contact (bacterial sex).
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

49. What is the chemical nomenclature for caffeine?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
1 - 3 - 7-trimethylxanthine
Bitter
Aspartic Acid and Phenylalanine

50. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Gliadins and Glutenins
It explodes
Monosodium Glutamate