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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. Define molarity molality - and normality.
Nucleation or crystal formation and crystal growth.
Arachidonic Acid
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Initiation - Propagation - and Termination

2. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
2.5
ERH=100 x Aw
Non-protein nitrogen
They act as catalysts - speeding the polymerization of acrylamide.

3. What is the acid present in fish oil?
Arachidonic Acid
Milk
Chlocophyllide does not have a phytoltail
Carrageenan

4. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Tryptophan
Anthocyanins
Lamellar; Hexagonal I - II; Cubic
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.

5. What is the structural difference between chlorophyll and pheophytia?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Pheophytia does not have magnesium in porphyrin ring.
Prolamines
20 carbons and 4 double bonds

6. Will lipid oxidation be higher at a water activity of .05 or .5?
DNA transferred by cell to cell contact (bacterial sex).
.05
Glycosides of anthocyanidins
Lamellar; Hexagonal I - II; Cubic

7. Name a commonly used household chemical leavening agent and the gas it generates.
Chlocophyllide does not have a phytoltail
Polyphenol Oxidase
Phenylketonuria
Sodium bicarbonate generates CO2

8. In genetics What is conjugation?
V=IR and P=VI or I x I x are
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).
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.

9. Name two enzymes that are involved in softening fruits.
It explodes
Pectin Esterase - Polygalacturonase - Pectin Layase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Oil in Water

10. Name 5 proteins with good foaming properties.
Pectin methylesterase & polygalacturonase
Lipid oxidation
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.
Water

11. Name three factors useful in controlling enzyme activity.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Emulsoids
45% - 52% - 90%
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

12. Contains the lowest content of water
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Whole Milk
DNA transferred by cell to cell contact (bacterial sex).
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.

13. At low water activity What is the main deteriorative concern?
NaCl (it dissociated to a 2M solution)
Lipid oxidation
Milk
Prolamines

14. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Bitter
Anomeric
.05

15. Name three effects of protein denaturation.
Monosodium Glutamate
Erythorbic Acid
Troponins and Tropomyosin
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

16. How many polypeptide chains make up an antibody?
Four
Ascorbic Acid and Citric Acid
Arachidonic Acid
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

17. What are the four basic flavors perceived by the tongue?
Speed of Light
Thamautin
Sweet - Salty - Sour - and Bitter
Cis

18. What is acid proteolysis?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Degradation of protein and production of acid from sugar at the same time.
Lysine - Arginine - and Histidine
Chitin

19. Name one way foam stability can be assessed.
Anthocyanins
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
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.
Acsulfame-K - Saccharin - Cyclamate - Aspartame

20. What effect would the addition of sodium bicarbonate have to chocolate?
Glycosides of anthocyanidins
Polyphenoloxidase
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

21. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Pectins
Emulsification
Milk
Carmelization and Maillard

22. What is a polymorphism?
1 - 3 - 7-trimethylxanthine
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
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.

23. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
It explodes
Pheophytia does not have magnesium in porphyrin ring.
RNA transcribed to DNA
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

24. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Glycosides of anthocyanidins
Initiation - Propagation - and Termination
Plasmids
Primary butyric acid also caproic acid.

25. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Pectins
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Chitin
Daminozide

26. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
Acsulfame-K - Saccharin - Cyclamate - Aspartame
2.5
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

27. How many polypeptide chains make up an antibody?
Four
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
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

28. What is the name of the degradation compound of chlorophyll?
Yellow
Phenophylin
20 carbons and 4 double bonds
Arachidonic Acid

29. Name three non-nutritive sweeteners approved for use in USA?
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.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Phenophylin

30. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Blue pigment in flowers
Linoleic Acid
2.5
Four

31. Which two amino acids is the aspartame derived from?
Yellow
Polyphenol Oxidase
Aspartic Acid and Phenylalanine
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

32. Name 3 factors influencing the consistency of commercial fats.
Parabens
Anomeric
Degradation of protein and production of acid from sugar at the same time.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

33. Alar is the trade name for what chemical compound?
Chitin
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.
Initiation - Propagation - and Termination
Daminozide

34. What are the limiting amino acids in corn - potato - and green peas?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Lysine - Arginine - and Histidine
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

35. When heated ammonium bicarbonate decomposes to form what end products?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Ammonia - Water - Carbon Dioxide
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

36. 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?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
.05 M HCL
Speed of Light

37. Peptide bond formation results in the formation of what secondary compound?
Water
Cis
Two aldehydes
Lysine - Arginine - and Histidine

38. Does kosmotrophil ion discourage water structure?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
No
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.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

39. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Negative log of the hydrogen concentration (mol/l).
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
Onions ( or leeks)

40. Which two amino acids is the aspartame derived from?
Thamautin
Four
Initiation - Propagation - and Termination
Aspartic Acid and Phenylalanine

41. What charge will a protein have when the pH of its solution is below at - and above its pKa?
pH below positive charge; pH at no charge; pH above negative charge
Pectin methylesterase & polygalacturonase
.05
Primary butyric acid also caproic acid.

42. What is the Peroxide Value a measure of?
Fat Oxidation
Erythorbic Acid
V=IR and P=VI or I x I x are
Yellow

43. What is the winterization process for an oil?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Fatty Acid (Ester linked) to Fatty Alcohol
Initiation - Propagation - and Termination

44. At low water activity What is the main deteriorative concern?
They act as catalysts - speeding the polymerization of acrylamide.
Lipid oxidation
It explodes
NaCl (it dissociated to a 2M solution)

45. What does the 'c' stand for in the equation E=mc2?
Speed of Light
Arachidonic Acid
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Phenophylin

46. Name the three positively charged amino acids.
DNA transferred by cell to cell contact (bacterial sex).
Lysine - Arginine - and Histidine
Speed of Light
Pectin Esterase

47. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
Lipase
Yes
Initiation - Propagation - Termination

48. What are two common reducing agents that break disulfide bonds in proteins?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Yellow
Linoleic Acid
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

49. How is pH defined?
Negative log of the hydrogen concentration (mol/l).
An enzyme that converts hydrogen peroxide to water plus oxygen.
Degradation of protein and production of acid from sugar at the same time.
They act as catalysts - speeding the polymerization of acrylamide.

50. What pigment was first designated as anthocyanins?
Degradation of protein and production of acid from sugar at the same time.
Blue pigment in flowers
HPLC has higher pressure than FPLC
Osmosis