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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 are the three stages of oxidative rancidity?
pH 3-5
Covalent (strongest) and Hydrophobic (Weakest)
Initiation - Propagation - and Termination
Pectin methyl esterase or galacturonase

2. Alar is the trade name for what chemical compound?
Primary butyric acid also caproic acid.
Daminozide
Carrageenan
Acetoin

3. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Orange Juice
Oil in Water
NaCl (it dissociated to a 2M solution)

4. What is an isomer that is cheaper than Vitamin C?
Fat Oxidation
Erythorbic Acid
Four
A concentrate of microfibrillar proteins of fish muscle.

5. What is the winterization process for an oil?
DNA transferred by cell to cell contact (bacterial sex).
V=IR and P=VI or I x I x are
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
pH below positive charge; pH at no charge; pH above negative charge

6. Name 3 factors influencing the consistency of commercial fats.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
.05
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Sodium chloride reduces foam stability and sucrose improves foam stability.

7. What is the acid present in fish oil?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Arachidonic Acid
Ammonia - Water - Carbon Dioxide
Sodium bicarbonate generates CO2

8. What two enzymes degrade pectic substances?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Daminozide
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Pectin methylesterase & polygalacturonase

9. What would be a safe processing time for heat processing green beans in a boiling water bath? A. 30 minutes B. 300 minutes C. Depends on the size of the food container D. None of the above
Thamautin
Monosodium Glutamate
Blue pigment in flowers
D: None of the above

10. What are colloids that are stabilized by a layer of solvation called?
Linoleic Acid
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.
Emulsoids

11. 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?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Two aldehydes
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

12. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
RNA transcribed to DNA
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Primary butyric acid also caproic acid.

13. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Monosodium Glutamate
Plasmids
.05 M HCL

14. What are two common reducing agents that break disulfide bonds in 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
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Water
No

15. What does HLB stand for and What does a high and low HLB value indicate?
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.
A concentrate of microfibrillar proteins of fish muscle.
Lipase
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

16. What is the protein efficiency ratio (PER) of casein?
Bright green
2.5
Monosodium Glutamate
Pectin methylesterase & polygalacturonase

17. Name three non-nutritive sweeteners approved for use in USA?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Anomeric
Acsulfame-K - Saccharin - Cyclamate - Aspartame

18. What are soluble polymers of anhydro-galacturonic acid and its esters called?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Thermus Aqauticus
Pectins
Erythorbic Acid

19. What are two common reducing agents that break disulfide bonds in proteins?
2.5
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Sweet - Salty - Sour - and Bitter
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

20. Name two non-enzymatic browning reactions.
.05 M HCL
Oil in Water
Pectins
Carmelization and Maillard

21. How can a molecular weight of protein - DNA - and RNA be determined?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
RNA transcribed to DNA
Troponins and Tropomyosin
1 - 3 - 7-trimethylxanthine

22. Name two reasons why fats are hydrogenated.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Pheophytia does not have magnesium in porphyrin ring.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
It explodes

23. Does kosmotrophil ion discourage water structure?
No
Plasmids
Emulsoids
Pectin methylesterase & polygalacturonase

24. What are the three stages of oxidative rancidity?
.05
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Ammonia - Water - Carbon Dioxide
Initiation - Propagation - and Termination

25. What is surimi?
Fatty Acid (Ester linked) to Fatty Alcohol
Pectin Esterase - Polygalacturonase - Pectin Layase
A concentrate of microfibrillar proteins of fish muscle.
Blue pigment in flowers

26. What are proteins which are soluble in 50-80% ethanol known as?
Daminozide
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Prolamines
An enzyme that converts hydrogen peroxide to water plus oxygen.

27. What is the name of the degradation compound of chlorophyll?
Phenophylin
pH 3-5
45% - 52% - 90%
Thamautin

28. How many polypeptide chains make up an antibody?
Sucrose
Four
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
45% - 52% - 90%

29. What are the three main steps in the autooxidation of lipids?
They act as catalysts - speeding the polymerization of acrylamide.
No
Initiation - Propagation - Termination
Ascorbic Acid and Citric Acid

30. Name 3 chemical agents capable of denaturing proteins.
Initiation - Propagation - Termination
Lycopenes
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

31. What is the protein efficiency ratio (PER) of casein?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
2.5
Chitin

32. Name 5 proteins with good foaming properties.
Lipid oxidation
Onions ( or leeks)
Phenylketonuria
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.

33. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Milk
A concentrate of microfibrillar proteins of fish muscle.
Carrageenan
Daminozide

34. Waxes are composed of what two basic chemical entities?
Aspartic Acid and Phenylalanine
Emulsification
Fatty Acid (Ester linked) to Fatty Alcohol
Sodium bicarbonate generates CO2

35. Which two amino acids is the aspartame derived from?
Racemic Mixture
Aspartic Acid and Phenylalanine
Gliadins and Glutenins
Two aldehydes

36. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Primary butyric acid also caproic acid.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Bright green

37. What is acid proteolysis?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
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.
No
Degradation of protein and production of acid from sugar at the same time.

38. Name three factors useful in controlling enzyme activity.
Thermus Aqauticus
.05 M HCL
Negative log of the hydrogen concentration (mol/l).
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

39. Name 5 proteins with good foaming properties.
Degradation of protein and production of acid from sugar at the same time.
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.
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.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

40. Name 4 advantages of using enzymes in food processing.
Gossypol (it is removed during the oil refining process)
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
Pectin methylesterase & polygalacturonase
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

41. Define molarity molality - and normality.
Pectins
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Primary butyric acid also caproic acid.
Four

42. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Pectins
Thickener in foods

43. What are the primary secondary - tertiary - and quaternary structures?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
RNA transcribed to DNA
Carrageenan
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.

44. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
They act as catalysts - speeding the polymerization of acrylamide.
Pectin Esterase
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

45. Name a commonly used household chemical leavening agent and the gas it generates.
Pectins
Acetoin
Sodium bicarbonate generates CO2
Gossypol (it is removed during the oil refining process)

46. Will lipid oxidation be higher at a water activity of .05 or .5?
.05
Pectin methylesterase & polygalacturonase
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Oil in Water

47. Name 4 advantages of using enzymes in food processing.
ERH=100 x Aw
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
Gliadins and Glutenins
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

48. Alar is the trade name for what chemical compound?
Daminozide
Negative log of the hydrogen concentration (mol/l).
Acetoin
Degradation of protein and production of acid from sugar at the same time.

49. Name three effects of protein denaturation.
V=IR and P=VI or I x I x are
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Sweet - Salty - Sour - and Bitter

50. How do sodium chloride and sucrose affect foam stability?
Sweet - Salty - Sour - and Bitter
Osmosis
Sodium chloride reduces foam stability and sucrose improves foam stability.
Thamautin