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Food Chemistry

Instructions:

Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What does MSG stand for?
Cis
Monosodium Glutamate
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Covalent (strongest) and Hydrophobic (Weakest)

2. Alar is the trade name for what chemical compound?
Degradation of protein and production of acid from sugar at the same time.
Polyphenol Oxidase
Daminozide
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.

3. Peptide bond formation results in the formation of what secondary compound?
RNA transcribed to DNA
Water
Fatty Acid (Ester linked) to Fatty Alcohol
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

4. 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?
An enzyme that converts hydrogen peroxide to water plus oxygen.
.05 M HCL
Lamellar; Hexagonal I - II; Cubic
Sweet - Salty - Sour - and Bitter

5. What is the enzyme that softens tomatoes?
Lipase
Negative log of the hydrogen concentration (mol/l).
Racemic Mixture
Pectin Esterase

6. What are two common reducing agents that break disulfide bonds in proteins?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Blue pigment in flowers
Gliadins and Glutenins
Plasmids

7. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Polyphenoloxidase
Two aldehydes
Troponins and Tropomyosin
Racemic Mixture

8. What is the Peroxide Value a measure of?
Glycosides of anthocyanidins
Fat Oxidation
An enzyme that converts hydrogen peroxide to water plus oxygen.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

9. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
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
Sodium chloride reduces foam stability and sucrose improves foam stability.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

10. Name three non-nutritive sweeteners approved for use in USA?
Monosodium Glutamate
Acsulfame-K - Saccharin - Cyclamate - Aspartame
pH below positive charge; pH at no charge; pH above negative charge
Pectins

11. In genetics What is conjugation?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Pectin methylesterase & polygalacturonase
DNA transferred by cell to cell contact (bacterial sex).
Pectin Esterase - Polygalacturonase - Pectin Layase

12. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
Pheophytin forms
Sucrose
Speed of Light

13. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
Fatty Acid (Ester linked) to Fatty Alcohol
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
20 carbons and 4 double bonds

14. Name 5 chelating agents used in the food industry.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Olive Green
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

15. Name the strongest biochemical bond and the weakest biochemical bond.
Emulsoids
Daminozide
Covalent (strongest) and Hydrophobic (Weakest)
Thamautin

16. At what pH is benzoic acid most effective?
pH 3-5
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Non-protein nitrogen

17. How is pH defined?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
pH below positive charge; pH at no charge; pH above negative charge
Blue pigment in flowers
Negative log of the hydrogen concentration (mol/l).

18. What is the structural difference between chlorophyll and chlocophyllide?
Chlocophyllide does not have a phytoltail
Lipid oxidation
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.
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

19. What is the chemical nomenclature for caffeine?
1 - 3 - 7-trimethylxanthine
They act as catalysts - speeding the polymerization of acrylamide.
Ammonia - Water - Carbon Dioxide
Fatty Acid (Ester linked) to Fatty Alcohol

20. What is the winterization process for an oil?
Osmosis
20 carbons and 4 double bonds
Pheophytin forms
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

21. What is the enzyme responsible for browning in apples and lettuce?
Cis
D: None of the above
Daminozide
Polyphenol Oxidase

22. How does HPLC differ from FPLC?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
HPLC has higher pressure than FPLC
Acetoin
14

23. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
It explodes
Chitin
Two aldehydes
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

24. What is the main class of color compounds found in raspberries?
HPLC has higher pressure than FPLC
Anthocyanins
Negative log of the hydrogen concentration (mol/l).
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

25. What are two common reducing agents that break disulfide bonds in proteins?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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).
Nucleation or crystal formation and crystal growth.

26. What effect would the addition of sodium bicarbonate have to chocolate?
Chitin
Negative log of the hydrogen concentration (mol/l).
Initiation - Propagation - Termination
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

27. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Phenylketonuria
Oil in Water
They act as catalysts - speeding the polymerization of acrylamide.

28. Alar is the trade name for what chemical compound?
Daminozide
Polyphenol Oxidase
Pectins
Fatty Acid and Alcohol

29. What is acid proteolysis?
Racemic Mixture
Acsulfame-K - Saccharin - Cyclamate - Aspartame
20 carbons and 4 double bonds
Degradation of protein and production of acid from sugar at the same time.

30. What does the 'c' stand for in the equation E=mc2?
Two aldehydes
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Speed of Light
Tryptophan

31. Waxes are composed of what two basic chemical entities?
Fatty Acid (Ester linked) to Fatty Alcohol
pH below positive charge; pH at no charge; pH above negative charge
Anomeric
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.

32. 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
ERH=100 x Aw
Linoleic Acid

33. How many polypeptide chains make up an antibody?
45% - 52% - 90%
Carmelization and Maillard
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Four

34. What enzyme causes hyrolytic rancidity in milk?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Cis
Lipase
Fat Oxidation

35. At low water activity What is the main deteriorative concern?
V=IR and P=VI or I x I x are
Yes
Lipid oxidation
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

36. Name two enzymes that are involved in softening fruits.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Speed of Light
Pectin Esterase - Polygalacturonase - Pectin Layase
Bright green

37. What two enzymes degrade pectic substances?
Thermus Aqauticus
Pectin methylesterase & polygalacturonase
2.5
DNA transferred by cell to cell contact (bacterial sex).

38. Are sorbitol and mannitol sweet?
Tryptophan
Yellow
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.
Yes

39. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Prolamines
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

40. 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.
Parabens
Nucleation or crystal formation and crystal growth.
45% - 52% - 90%

41. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Initiation - Propagation - and Termination
Sucrose
Pectin methyl esterase or galacturonase
Sodium bicarbonate generates CO2

42. What metabolic end product does the Voges-Proskauer test detect?
Thickener in foods
Chlocophyllide does not have a phytoltail
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Acetoin

43. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Ascorbic Acid and Citric Acid
Bright green
pH 3-5
Linoleic Acid

44. How does ERH relate to water activity?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
.05 M HCL
Emulsification
ERH=100 x Aw

45. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Bitter
Pectins

46. In the enzyme Taq Polymerase What does Taq stand for?
Thermus Aqauticus
Pectin methylesterase & polygalacturonase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Phenophylin

47. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
HPLC has higher pressure than FPLC
45% - 52% - 90%
Ascorbic Acid and Citric Acid
Capsaicin

48. What is the major color compound in tomatoes?
Lysine - Arginine - and Histidine
pH 3-5
Glycosides of anthocyanidins
Lycopenes

49. What is Carboxy-methyl cellulose often used for?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Polyphenoloxidase
Thickener in foods
Lycopenes

50. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Degradation of protein and production of acid from sugar at the same time.
Thermus Aqauticus
NaCl (it dissociated to a 2M solution)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)