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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 effect would the addition of sodium bicarbonate have to chocolate?
Daminozide
It explodes
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).

2. What is the protein efficiency ratio (PER) of casein?
Speed of Light
Sucrose
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
2.5

3. Name the three positively charged amino acids.
Two aldehydes
Capsaicin
Prolamines
Lysine - Arginine - and Histidine

4. What are the four basic flavors perceived by the tongue?
Pheophytia does not have magnesium in porphyrin ring.
Sweet - Salty - Sour - and Bitter
Nucleation or crystal formation and crystal growth.
Arachidonic Acid

5. When heated ammonium bicarbonate decomposes to form what end products?
Pheophytin forms
Initiation - Propagation - Termination
Ammonia - Water - Carbon Dioxide
Aspartic Acid and Phenylalanine

6. What is the chemical nature of anthocyanins?
Gliadins and Glutenins
Glycosides of anthocyanidins
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

7. At low water activity What is the main deteriorative concern?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Daminozide
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Lipid oxidation

8. Name the two components that comprise the relaxing factor in muscle fibers.
Parabens
Troponins and Tropomyosin
Pectin methylesterase & polygalacturonase
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.

9. What two enzymes degrade pectic substances?
Sodium bicarbonate generates CO2
Ascorbic Acid and Citric Acid
Yellow
Pectin methylesterase & polygalacturonase

10. Name 3 factors influencing the consistency of commercial fats.
Anthocyanins
Acsulfame-K - Saccharin - Cyclamate - Aspartame
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

11. In what food is butyric acid typically found?
The speed of a molecule is proportional to the surrounding voltage gradient.
Monosodium Glutamate
Polyphenoloxidase
Milk

12. In what food is butyric acid typically found?
Fat Oxidation
Glycosides of anthocyanidins
No
Milk

13. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Olive Green
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Thermus Aqauticus
Acsulfame-K - Saccharin - Cyclamate - Aspartame

14. What is the name given to a mixture of equal parts of Darel Lisomers?
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.
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.
Racemic Mixture

15. What is an isomer that is cheaper than Vitamin C?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Erythorbic Acid
Lipid oxidation
Pectin Esterase

16. Match the number of carbon atoms with the common name of these saturated fatty acids. Carbon #: 4:0 10:0 - 12:0 -14:0 - 16:0 - 18:0Common Name: Myristic - Butyric - Capric - Lauric - Stearic - Palmitic
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Fat Oxidation

17. What does the acronym NPN stand for?
Pectin Esterase - Polygalacturonase - Pectin Layase
pH 3-5
Non-protein nitrogen
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.

18. Name a naturally occurring protein sweetener.
Pheophytia does not have magnesium in porphyrin ring.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Thamautin
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.

19. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Four
1 - 3 - 7-trimethylxanthine

20. What does the 'c' stand for in the equation E=mc2?
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.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Speed of Light

21. Name two enzymes that are involved in softening fruits.
D: None of the above
ERH=100 x Aw
Chlocophyllide does not have a phytoltail
Pectin Esterase - Polygalacturonase - Pectin Layase

22. 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
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Cis
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.

23. What enzyme causes hyrolytic rancidity in milk?
Daminozide
Lipase
Chlocophyllide does not have a phytoltail
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

24. In genetics What is conjugation?
Water
DNA transferred by cell to cell contact (bacterial sex).
Lycopenes
Pectin methyl esterase or galacturonase

25. Contains the lowest content of water
Whole Milk
Emulsoids
Sodium bicarbonate generates CO2
Polyphenol Oxidase

26. What ketohexose is most significant to food chemists?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Fructose
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Capsaicin

27. What are soluble polymers of anhydro-galacturonic acid and its esters called?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Whole Milk
Pectins
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

28. Name three factors useful in controlling enzyme activity.
Pectin Esterase
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Prolamines
Water

29. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
D: None of the above
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Thickener in foods
Polyphenoloxidase

30. Name one way foam stability can be assessed.
Sucrose
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.
Ascorbic Acid and Citric Acid
Lamellar; Hexagonal I - II; Cubic

31. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Pectin methylesterase & polygalacturonase
Linoleic Acid
Pectin methyl esterase or galacturonase
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

32. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Degradation of protein and production of acid from sugar at the same time.
Bright green
Pectin Esterase - Polygalacturonase - Pectin Layase

33. What two types of compounds are joined with an ester bond to make a wax?
45% - 52% - 90%
Negative log of the hydrogen concentration (mol/l).
Polyphenol Oxidase
Fatty Acid and Alcohol

34. What is the geometric configuration of double bonds in most natural fatty acids?
Pectins
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
V=IR and P=VI or I x I x are
Cis

35. What is acid proteolysis?
Ammonia - Water - Carbon Dioxide
Water
Olive Green
Degradation of protein and production of acid from sugar at the same time.

36. What are the limiting amino acids in corn - potato - and green peas?
Negative log of the hydrogen concentration (mol/l).
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
14

37. Name three non-nutritive sweeteners approved for use in USA?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Water
Lysine - Arginine - and Histidine
The speed of a molecule is proportional to the surrounding voltage gradient.

38. What enzyme causes hyrolytic rancidity in milk?
Lipase
Ammonia - Water - Carbon Dioxide
Acetoin
Lamellar; Hexagonal I - II; Cubic

39. How many carbon atoms and how many double bonds are there in arachidonic acid?
Anthocyanins
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
20 carbons and 4 double bonds
Daminozide

40. Waxes are composed of what two basic chemical entities?
Fatty Acid (Ester linked) to Fatty Alcohol
Thermus Aqauticus
They act as catalysts - speeding the polymerization of acrylamide.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

41. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Arachidonic Acid
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.
Bitter
Initiation - Propagation - Termination

42. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pheophytia does not have magnesium in porphyrin ring.
Pectin methyl esterase or galacturonase
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
D: None of the above

43. What effect would the addition of sodium bicarbonate have to chocolate?
pH below positive charge; pH at no charge; pH above negative charge
The speed of a molecule is proportional to the surrounding voltage gradient.
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.

44. Name three factors useful in controlling enzyme activity.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Gliadins and Glutenins
Whole Milk
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

45. What happens to chlorophyll on heating?
Emulsification
Pheophytin forms
Parabens
Glycosides of anthocyanidins

46. Name the strongest biochemical bond and the weakest biochemical bond.
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.
Covalent (strongest) and Hydrophobic (Weakest)
It explodes
Bitter

47. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Gossypol (it is removed during the oil refining process)
Ammonia - Water - Carbon Dioxide
Carmelization and Maillard
Yellow

48. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
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.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
20 carbons and 4 double bonds
RNA transcribed to DNA

49. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
Gliadins and Glutenins
Racemic Mixture
Orange Juice

50. What does Reichert-Meissert Number measure?
Primary butyric acid also caproic acid.
RNA transcribed to DNA
Chlocophyllide does not have a phytoltail
HPLC has higher pressure than FPLC