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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 is the fundamental driving of electrophoresis?
Arachidonic Acid
The speed of a molecule is proportional to the surrounding voltage gradient.
Erythorbic Acid
Bitter

2. 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?
Browning of freshly cut surfaces of fruits and vegetables.
Daminozide
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Water

3. Name three nonpolar polar - and charged amino acids.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
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.
Blue pigment in flowers
Phenylketonuria

4. What happens to chlorophyll on heating?
Pectin Esterase
Erythorbic Acid
Pheophytin forms
Anomeric

5. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Fatty Acid (Ester linked) to Fatty Alcohol
Lysine - Arginine - and Histidine
Primary butyric acid also caproic acid.
Linoleic Acid

6. What does the acronym NPN stand for?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Non-protein nitrogen
Acetoin

7. In what food is butyric acid typically found?
Yes
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Milk
Water

8. 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
Capsaicin
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Speed of Light
Troponins and Tropomyosin

9. How can a molecular weight of protein - DNA - and RNA be determined?
Pectin Esterase - Polygalacturonase - Pectin Layase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Two aldehydes
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.

10. Name the most common functional property of phospholipids in food systems.
Polyphenol Oxidase
Polyphenols
Emulsification
Linoleic Acid

11. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
.05 M HCL
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Olive Green

12. Name 5 proteins with good foaming properties.
Gliadins and Glutenins
Fatty Acid and Alcohol
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.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

13. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
Arachidonic Acid
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Carmelization and Maillard

14. What two enzymes degrade pectic substances?
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.
Pectin methylesterase & polygalacturonase
Water
Plasmids

15. Which two amino acids is the aspartame derived from?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
DNA transferred by cell to cell contact (bacterial sex).
Aspartic Acid and Phenylalanine
Polyphenol Oxidase

16. 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.
2.5
Tryptophan
20 carbons and 4 double bonds

17. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
pH 3-5
Nucleation or crystal formation and crystal growth.
20 carbons and 4 double bonds

18. Name a naturally occurring protein sweetener.
Thamautin
Pectins
Non-protein nitrogen
Capsaicin

19. What are colloids that are stabilized by a layer of solvation called?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
They act as catalysts - speeding the polymerization of acrylamide.
Emulsoids
Capsaicin

20. How many polypeptide chains make up an antibody?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Four
Pectin methyl esterase or galacturonase
Lipase

21. How many carbon atoms are there in the fatty acid myristic acid?
DNA transferred by cell to cell contact (bacterial sex).
14
V=IR and P=VI or I x I x are
.05 M HCL

22. What is a polymorphism?
.05
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Daminozide
DNA transferred by cell to cell contact (bacterial sex).

23. 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?
Anthocyanins
It explodes
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

24. Name 3 chemical agents capable of denaturing proteins.
Pectin Esterase
Ammonia - Water - Carbon Dioxide
They act as catalysts - speeding the polymerization of acrylamide.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

25. Name two non-enzymatic browning reactions.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Carmelization and Maillard
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Blue pigment in flowers

26. What does Reichert-Meissert Number measure?
Gossypol (it is removed during the oil refining process)
14
Primary butyric acid also caproic acid.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

27. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
Prolamines
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic 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.

28. Name one way foam stability can be assessed.
Blue pigment in flowers
Linoleic Acid
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
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.

29. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
It explodes
Acsulfame-K - Saccharin - Cyclamate - Aspartame
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.
Oil in Water

30. What are the three main steps in the autooxidation of lipids?
Pectin methyl esterase or galacturonase
Phenylketonuria
Negative log of the hydrogen concentration (mol/l).
Initiation - Propagation - Termination

31. What does Acid Degree Value measure and how is it measured?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
1 - 3 - 7-trimethylxanthine
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Pheophytia does not have magnesium in porphyrin ring.

32. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
Carrageenan
NaCl (it dissociated to a 2M solution)
Carrageenan

33. Are sorbitol and mannitol sweet?
Cis
Parabens
Ascorbic Acid and Citric Acid
Yes

34. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
pH 3-5

35. Does kosmotrophil ion discourage water structure?
Yes
No
Polyphenol Oxidase
Polyphenoloxidase

36. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
They act as catalysts - speeding the polymerization of acrylamide.
Polyphenol Oxidase
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

37. What is surimi?
Pheophytin forms
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.
Initiation - Propagation - Termination
A concentrate of microfibrillar proteins of fish muscle.

38. What is the winterization process for an oil?
Chlocophyllide does not have a phytoltail
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Pheophytia does not have magnesium in porphyrin ring.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

39. What two types of compounds are joined with an ester bond to make a wax?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Linoleic Acid
Fatty Acid and Alcohol
Emulsification

40. What does MSG stand for?
Sweet - Salty - Sour - and Bitter
Tryptophan
Monosodium Glutamate
Sodium bicarbonate generates CO2

41. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Polyphenols
NaCl (it dissociated to a 2M solution)
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
The speed of a molecule is proportional to the surrounding voltage gradient.

42. What is the chemical nomenclature for caffeine?
Browning of freshly cut surfaces of fruits and vegetables.
They act as catalysts - speeding the polymerization of acrylamide.
1 - 3 - 7-trimethylxanthine
pH below positive charge; pH at no charge; pH above negative charge

43. Contains the lowest content of water
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
The speed of a molecule is proportional to the surrounding voltage gradient.
Whole Milk
Anthocyanins

44. What does HLB stand for and What does a high and low HLB value indicate?
Pheophytia does not have magnesium in porphyrin ring.
Gliadins and Glutenins
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
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.

45. What effect would the addition of sodium bicarbonate have to chocolate?
Sweet - Salty - Sour - and Bitter
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

46. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
Yes
Lipase
D: None of the above

47. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
20 carbons and 4 double bonds
20 carbons and 4 double bonds
Olive Green
Pectin methylesterase & polygalacturonase

48. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Aspartic Acid and Phenylalanine
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
NaCl (it dissociated to a 2M solution)
2.5

49. 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
Anomeric
14
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

50. 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?
.05 M HCL
Linoleic Acid
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
Plasmids