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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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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 is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Osmosis
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

2. What two common compounds are used together as an antioxidative system?
Onions ( or leeks)
Pheophytia does not have magnesium in porphyrin ring.
Ascorbic Acid and Citric Acid
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

3. What is the main class of color compounds found in raspberries?
Yes
Acetoin
Polyphenoloxidase
Anthocyanins

4. Name two non-enzymatic browning reactions.
Browning of freshly cut surfaces of fruits and vegetables.
Chitin
Carmelization and Maillard
Sweet - Salty - Sour - and Bitter

5. In the enzyme Taq Polymerase What does Taq stand for?
Daminozide
Negative log of the hydrogen concentration (mol/l).
Parabens
Thermus Aqauticus

6. Name 5 proteins with good foaming properties.
Sodium bicarbonate generates CO2
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.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Chlocophyllide does not have a phytoltail

7. What enzyme causes hyrolytic rancidity in milk?
Pectin Esterase
Plasmids
Lipase
Polyphenols

8. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
DNA transferred by cell to cell contact (bacterial sex).
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Chlocophyllide does not have a phytoltail

9. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Racemic Mixture
Pheophytin forms
A concentrate of microfibrillar proteins of fish muscle.

10. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Chitin
2.5
Fatty Acid and Alcohol
The speed of a molecule is proportional to the surrounding voltage gradient.

11. In genetics What is conjugation?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
DNA transferred by cell to cell contact (bacterial sex).
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.

12. 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)
Chlocophyllide does not have a phytoltail
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
HPLC has higher pressure than FPLC

13. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Osmosis
Thickener in foods
Olive Green
Prolamines

14. In genetics What is conjugation?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Chlocophyllide does not have a phytoltail
RNA transcribed to DNA
DNA transferred by cell to cell contact (bacterial sex).

15. What ketohexose is most significant to food chemists?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Fructose
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Anomeric

16. What metabolic end product does the Voges-Proskauer test detect?
Negative log of the hydrogen concentration (mol/l).
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Pectins
Acetoin

17. What two common compounds are used together as an antioxidative system?
Water
Thamautin
Acetoin
Ascorbic Acid and Citric Acid

18. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Bitter
Pectins
Non-protein nitrogen
Primary butyric acid also caproic acid.

19. What two enzymes degrade pectic substances?
Lipase
Anthocyanins
Pectin methylesterase & polygalacturonase
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.

20. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Linoleic Acid
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
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Osmosis

21. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Pectin Esterase - Polygalacturonase - Pectin Layase
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Primary butyric acid also caproic acid.

22. What is Ohm's Law and What is Power Equation?
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 - and Termination
Browning of freshly cut surfaces of fruits and vegetables.
V=IR and P=VI or I x I x are

23. What is the name of the degradation compound of chlorophyll?
Linoleic Acid
Phenophylin
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

24. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Anthocyanins
Gliadins and Glutenins
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
They act as catalysts - speeding the polymerization of acrylamide.

25. Peptide bond formation results in the formation of what secondary compound?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Primary butyric acid also caproic acid.
Water
NaCl (it dissociated to a 2M solution)

26. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
.05 M HCL
Fructose
Two aldehydes

27. What pigment was first designated as anthocyanins?
Polyphenol Oxidase
Blue pigment in flowers
Covalent (strongest) and Hydrophobic (Weakest)
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

28. Name 3 chemical agents capable of denaturing proteins.
Pectins
Daminozide
Milk
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

29. What is the fundamental driving of electrophoresis?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Pheophytia does not have magnesium in porphyrin ring.
Negative log of the hydrogen concentration (mol/l).
The speed of a molecule is proportional to the surrounding voltage gradient.

30. During freezing What are the two stages in the crystallization process?
Orange Juice
Nucleation or crystal formation and crystal growth.
Lamellar; Hexagonal I - II; Cubic
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

31. Name 3 factors influencing the rate of lipid oxidation in foods.
Racemic Mixture
Milk
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

32. What are 3 mesomorphic structures associated with lipids in the liquid state?
Initiation - Propagation - Termination
Anomeric
Water
Lamellar; Hexagonal I - II; Cubic

33. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
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
Capsaicin
Prolamines

34. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
No
Bright green
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.
Capsaicin

35. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Water
Linoleic Acid

36. What compounds oxidize to form brown color in fruits and vegetables?
.05
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Polyphenols

37. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
ERH=100 x Aw
Polyphenoloxidase
Sodium bicarbonate generates CO2
Capsaicin

38. What does the 'c' stand for in the equation E=mc2?
Sucrose
Speed of Light
pH below positive charge; pH at no charge; pH above negative charge
Sodium chloride reduces foam stability and sucrose improves foam stability.

39. Name a commonly used household chemical leavening agent and the gas it generates.
pH below positive charge; pH at no charge; pH above negative charge
Two aldehydes
Sodium bicarbonate generates CO2
Sodium chloride reduces foam stability and sucrose improves foam stability.

40. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
They act as catalysts - speeding the polymerization of acrylamide.
Negative log of the hydrogen concentration (mol/l).
Orange Juice
.05

41. What does the 'c' stand for in the equation E=mc2?
Speed of Light
Daminozide
Two aldehydes
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.

42. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Pheophytia does not have magnesium in porphyrin ring.
Troponins and Tropomyosin
Linoleic Acid

43. What is the name given to a mixture of equal parts of Darel Lisomers?
Gossypol (it is removed during the oil refining process)
Racemic Mixture
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lipase

44. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Polyphenol Oxidase
Orange Juice
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Yellow

45. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
pH below positive charge; pH at no charge; pH above negative charge
Milk
Yellow
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

46. Name two non-enzymatic browning reactions.
Carmelization and Maillard
Milk
They act as catalysts - speeding the polymerization of acrylamide.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

47. 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
D: None of the above
Anomeric
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
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

48. Waxes are composed of what two basic chemical entities?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Gliadins and Glutenins
Fatty Acid (Ester linked) to Fatty Alcohol
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.

49. What are the primary secondary - tertiary - and quaternary structures?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Pectins
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
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.

50. What is the Peroxide Value a measure of?
Fat Oxidation
2.5
Initiation - Propagation - Termination
Gossypol (it is removed during the oil refining process)