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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. Name three factors useful in controlling enzyme activity.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Four
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

2. What enzyme causes hyrolytic rancidity in milk?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
DNA transferred by cell to cell contact (bacterial sex).
Two aldehydes
Lipase

3. 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?
Thamautin
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Phenylketonuria
DNA transferred by cell to cell contact (bacterial sex).

4. What are the limiting amino acids in corn - potato - and green peas?
Arachidonic Acid
Non-protein nitrogen
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

5. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Lycopenes
Troponins and Tropomyosin
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Plasmids

6. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Bitter
Yellow
Pectins
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

7. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Two aldehydes
An enzyme that converts hydrogen peroxide to water plus oxygen.
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.
D: None of the above

8. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Linoleic Acid
Pectin Esterase - Polygalacturonase - Pectin Layase

9. What is the structural difference between chlorophyll and chlocophyllide?
Chlocophyllide does not have a phytoltail
Arachidonic Acid
Initiation - Propagation - and Termination
Non-protein nitrogen

10. Is a disaccharide
Sucrose
ERH=100 x Aw
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Anomeric

11. In the enzyme Taq Polymerase What does Taq stand for?
Chitin
Thermus Aqauticus
Four
Erythorbic Acid

12. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Water
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Polyphenol Oxidase

13. What are the three stages of oxidative rancidity?
They act as catalysts - speeding the polymerization of acrylamide.
Initiation - Propagation - and Termination
Fructose
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

14. Name 4 advantages of using enzymes in food processing.
Gliadins and Glutenins
Anomeric
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
Lamellar; Hexagonal I - II; Cubic

15. What does HLB stand for and What does a high and low HLB value indicate?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Daminozide
Pectin Esterase - Polygalacturonase - Pectin Layase
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.

16. Name two main gluten proteins.
Lipid oxidation
Chlocophyllide does not have a phytoltail
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Gliadins and Glutenins

17. In genetics What is conjugation?
Water
Lamellar; Hexagonal I - II; Cubic
DNA transferred by cell to cell contact (bacterial sex).
Orange Juice

18. How many carbon atoms are there in the fatty acid myristic acid?
14
Bright green
Bright green
Thermus Aqauticus

19. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Covalent (strongest) and Hydrophobic (Weakest)
Initiation - Propagation - Termination
RNA transcribed to DNA
Bright green

20. Name the strongest biochemical bond and the weakest biochemical bond.
It explodes
Covalent (strongest) and Hydrophobic (Weakest)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
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

21. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Daminozide
Sodium bicarbonate generates CO2

22. Peptide bond formation results in the formation of what secondary compound?
Parabens
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Yes
Water

23. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
Four
Onions ( or leeks)
Lamellar; Hexagonal I - II; Cubic

24. How is pH defined?
Non-protein nitrogen
Thamautin
Negative log of the hydrogen concentration (mol/l).
pH 3-5

25. What does the saponification value measure and how is it measured?
The speed of a molecule is proportional to the surrounding voltage gradient.
.05
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Sodium bicarbonate generates CO2

26. What is the protein efficiency ratio (PER) of casein?
2.5
Capsaicin
Acetoin
Negative log of the hydrogen concentration (mol/l).

27. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
DNA transferred by cell to cell contact (bacterial sex).
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Bitter

28. Name 3 factors influencing the consistency of commercial fats.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Chitin
Pectin methyl esterase or galacturonase
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

29. What are the only phenols approved for use in the microbiological preservation of foods?
Thermus Aqauticus
Browning of freshly cut surfaces of fruits and vegetables.
Parabens
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.

30. What effect would the addition of sodium bicarbonate have to chocolate?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Daminozide
Anthocyanins
Gliadins and Glutenins

31. What pigment was first designated as anthocyanins?
Daminozide
Blue pigment in flowers
Chlocophyllide does not have a phytoltail
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

32. Name two enzymes that are involved in softening fruits.
45% - 52% - 90%
Erythorbic Acid
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pectin Esterase - Polygalacturonase - Pectin Layase

33. What are the primary secondary - tertiary - and quaternary structures?
Carrageenan
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
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.
Fatty Acid (Ester linked) to Fatty Alcohol

34. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
D: None of the above
Speed of Light
Linoleic Acid
Two aldehydes

35. Name a naturally occurring protein sweetener.
Initiation - Propagation - Termination
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.
Daminozide
Thamautin

36. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
Arachidonic Acid
Thermus Aqauticus
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

37. What does MSG stand for?
HPLC has higher pressure than FPLC
Milk
Lycopenes
Monosodium Glutamate

38. 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.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pectin Esterase
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

39. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Capsaicin
Non-protein nitrogen

40. What effect would the addition of sodium bicarbonate have to chocolate?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Phenylketonuria
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

41. What two enzymes degrade pectic substances?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Pectin methylesterase & polygalacturonase
Negative log of the hydrogen concentration (mol/l).
Thermus Aqauticus

42. How many carbon atoms and how many double bonds are there in arachidonic acid?
An enzyme that converts hydrogen peroxide to water plus oxygen.
The speed of a molecule is proportional to the surrounding voltage gradient.
Gliadins and Glutenins
20 carbons and 4 double bonds

43. What is acid proteolysis?
Olive Green
Degradation of protein and production of acid from sugar at the same time.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Negative log of the hydrogen concentration (mol/l).

44. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Yellow
Polyphenoloxidase
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
45% - 52% - 90%

45. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
14
Linoleic Acid
Chitin

46. What compounds oxidize to form brown color in fruits and vegetables?
They act as catalysts - speeding the polymerization of acrylamide.
Polyphenols
Linoleic Acid
Sucrose

47. 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?
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.
.05 M HCL
No

48. What pigment was first designated as anthocyanins?
Blue pigment in flowers
Lipase
Cis
Negative log of the hydrogen concentration (mol/l).

49. What are the four basic flavors perceived by the tongue?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Pectin methylesterase & polygalacturonase
Sweet - Salty - Sour - and Bitter
HPLC has higher pressure than FPLC

50. In what food is butyric acid typically found?
Emulsification
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.
Milk
Plasmids