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Food Chemistry

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Answer 50 questions in 15 minutes.
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1. Alar is the trade name for what chemical compound?
Nucleation or crystal formation and crystal growth.
Daminozide
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

2. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Chitin
Water
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Two aldehydes

3. What two enzymes degrade pectic substances?
Whole Milk
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.
Polyphenol Oxidase
Pectin methylesterase & polygalacturonase

4. Is a disaccharide
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
They act as catalysts - speeding the polymerization of acrylamide.
Sucrose
Pectin Esterase

5. Name 4 advantages of using enzymes in food processing.
D: None of the above
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
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
Initiation - Propagation - Termination

6. What is Carboxy-methyl cellulose often used for?
Lycopenes
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Thickener in foods
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.

7. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Sodium bicarbonate generates CO2
D: None of the above
Anomeric
ERH=100 x Aw

8. Name the three positively charged amino acids.
Cis
Fatty Acid and Alcohol
2.5
Lysine - Arginine - and Histidine

9. What are proteins which are soluble in 50-80% ethanol known as?
Speed of Light
Covalent (strongest) and Hydrophobic (Weakest)
Prolamines
Non-protein nitrogen

10. What are the primary secondary - tertiary - and quaternary structures?
Pheophytin forms
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.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Polyphenoloxidase

11. Name 3 physical agents capable of denaturing proteins.
Nucleation or crystal formation and crystal growth.
Pectin methylesterase & polygalacturonase
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

12. In the enzyme Taq Polymerase What does Taq stand for?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Emulsoids
Polyphenoloxidase
Thermus Aqauticus

13. How do sodium chloride and sucrose affect foam stability?
20 carbons and 4 double bonds
Sodium chloride reduces foam stability and sucrose improves foam stability.
Thamautin
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

14. What is the acid present in fish oil?
The speed of a molecule is proportional to the surrounding voltage gradient.
Degradation of protein and production of acid from sugar at the same time.
Arachidonic Acid
They act as catalysts - speeding the polymerization of acrylamide.

15. What ketohexose is most significant to food chemists?
DNA transferred by cell to cell contact (bacterial sex).
D: None of the above
Fructose
Carmelization and Maillard

16. Name 3 reasons it is advantageous to obtain enzymes from microorganisms.

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17. Name three factors useful in controlling enzyme activity.
Thickener in foods
Bitter
Polyphenol Oxidase
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

18. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Milk
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.
NaCl (it dissociated to a 2M solution)
Sodium bicarbonate generates CO2

19. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
NaCl (it dissociated to a 2M solution)
Nucleation or crystal formation and crystal growth.
Two aldehydes
Capsaicin

20. How does HPLC differ from FPLC?
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.
Pectin Esterase
HPLC has higher pressure than FPLC
Gossypol (it is removed during the oil refining process)

21. What is the structural difference between chlorophyll and pheophytia?
Initiation - Propagation - Termination
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Lycopenes
Pheophytia does not have magnesium in porphyrin ring.

22. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
pH below positive charge; pH at no charge; pH above negative charge
NaCl (it dissociated to a 2M solution)
D: None of the above

23. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Bright green
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

24. What is the main class of color compounds found in raspberries?
Anthocyanins
Lamellar; Hexagonal I - II; Cubic
Thermus Aqauticus
Fructose

25. How many carbon atoms are there in the fatty acid myristic acid?
Glycosides of anthocyanidins
Daminozide
Gossypol (it is removed during the oil refining process)
14

26. What happens to chlorophyll on heating?
Water
Pheophytin forms
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Osmosis

27. What is the name given to a mixture of equal parts of Darel Lisomers?
Osmosis
Anthocyanins
Monosodium Glutamate
Racemic Mixture

28. What does the acronym NPN stand for?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Non-protein nitrogen
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lysine - Arginine - and Histidine

29. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
HPLC has higher pressure than FPLC
They act as catalysts - speeding the polymerization of acrylamide.
Sweet - Salty - Sour - and Bitter

30. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Plasmids
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.

31. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
Non-protein nitrogen
Thickener in foods
Erythorbic Acid

32. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Aspartic Acid and Phenylalanine
pH below positive charge; pH at no charge; pH above negative charge
Tryptophan

33. What are colloids that are stabilized by a layer of solvation called?
Chlocophyllide does not have a phytoltail
Emulsoids
NaCl (it dissociated to a 2M solution)
Gliadins and Glutenins

34. Which two amino acids is the aspartame derived from?
DNA transferred by cell to cell contact (bacterial sex).
Fructose
The speed of a molecule is proportional to the surrounding voltage gradient.
Aspartic Acid and Phenylalanine

35. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Olive Green
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.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

36. Name 3 chemical agents capable of denaturing proteins.
pH 3-5
Sweet - Salty - Sour - and Bitter
Negative log of the hydrogen concentration (mol/l).
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

37. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Non-protein nitrogen
Polyphenol Oxidase
pH below positive charge; pH at no charge; pH above negative charge

38. Name a commonly used household chemical leavening agent and the gas it generates.
Water
Sodium bicarbonate generates CO2
Pectin Esterase - Polygalacturonase - Pectin Layase
Gossypol (it is removed during the oil refining process)

39. Name one way foam stability can be assessed.
Gossypol (it is removed during the oil refining process)
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.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Monosodium Glutamate

40. What does the iodine value measure and how is it measured?
Nucleation or crystal formation and crystal growth.
NaCl (it dissociated to a 2M solution)
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

41. What are colloids that are stabilized by a layer of solvation called?
Aspartic Acid and Phenylalanine
Emulsoids
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
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

42. What are the three main steps in the autooxidation of lipids?
Initiation - Propagation - Termination
ERH=100 x Aw
Pheophytia does not have magnesium in porphyrin ring.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

43. How does ERH relate to water activity?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
ERH=100 x Aw
No
DNA transferred by cell to cell contact (bacterial sex).

44. What does HLB stand for and What does a high and low HLB value indicate?
Linoleic 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.
Blue pigment in flowers
Racemic Mixture

45. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
No
Water
Chitin
Polyphenol Oxidase

46. What are the limiting amino acids in corn - potato - and green peas?
They act as catalysts - speeding the polymerization of acrylamide.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Non-protein nitrogen
Pectin Esterase - Polygalacturonase - Pectin Layase

47. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Pectin Esterase
Bright green
Emulsoids

48. Contains the lowest content of water
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.
Browning of freshly cut surfaces of fruits and vegetables.
Glycosides of anthocyanidins
Whole Milk

49. Will lipid oxidation be higher at a water activity of .05 or .5?
Carmelization and Maillard
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Pectin Esterase - Polygalacturonase - Pectin Layase
.05

50. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
Lycopenes
Daminozide
RNA transcribed to DNA
Onions ( or leeks)