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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 proteins which are soluble in 50-80% ethanol known as?
Prolamines
Fatty Acid and Alcohol
V=IR and P=VI or I x I x are
Daminozide

2. Name 5 chelating agents used in the food industry.
Blue pigment in flowers
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

3. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Speed of Light
Ascorbic Acid and Citric Acid

4. What does Reichert-Meissert Number measure?
Fat Oxidation
Primary butyric acid also caproic acid.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Gossypol (it is removed during the oil refining process)

5. What are two common reducing agents that break disulfide bonds in proteins?
Sucrose
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Whole Milk
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.

6. Will lipid oxidation be higher at a water activity of .05 or .5?
Tryptophan
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Gliadins and Glutenins
.05

7. What charge will a protein have when the pH of its solution is below at - and above its pKa?
pH below positive charge; pH at no charge; pH above negative charge
Anthocyanins
Water
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

8. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Two aldehydes
Pectins
pH below positive charge; pH at no charge; pH above negative charge
Lysine - Arginine - and Histidine

9. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Oil in Water
They act as catalysts - speeding the polymerization of acrylamide.
Fructose
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

10. In the enzyme Taq Polymerase What does Taq stand for?
D: None of the above
Thermus Aqauticus
Polyphenol Oxidase
Prolamines

11. What does the 'c' stand for in the equation E=mc2?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Speed of Light
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Fat Oxidation

12. What is an isomer that is cheaper than Vitamin C?
Chlocophyllide does not have a phytoltail
Glycosides of anthocyanidins
Erythorbic Acid
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

13. How many carbon atoms and how many double bonds are there in arachidonic acid?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Arachidonic Acid
Erythorbic Acid
20 carbons and 4 double bonds

14. Name two reasons why fats are hydrogenated.
Carmelization and Maillard
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Pectin methyl esterase or galacturonase
45% - 52% - 90%

15. What is the name of the degradation compound of chlorophyll?
Four
Pectin methylesterase & polygalacturonase
Anomeric
Phenophylin

16. 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.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
pH below positive charge; pH at no charge; pH above negative charge
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

17. What is the enzyme responsible for browning in apples and lettuce?
.05
Carmelization and Maillard
Polyphenol Oxidase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

18. Name three effects of protein denaturation.
HPLC has higher pressure than FPLC
Sodium chloride reduces foam stability and sucrose improves foam stability.
Polyphenol Oxidase
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

19. Name the strongest biochemical bond and the weakest biochemical bond.
Covalent (strongest) and Hydrophobic (Weakest)
Degradation of protein and production of acid from sugar at the same time.
Initiation - Propagation - and Termination
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

20. What does Acid Degree Value measure and how is it measured?
pH 3-5
Emulsoids
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
2.5

21. What is the enzyme that softens tomatoes?
Pectin Esterase
Aspartic Acid and Phenylalanine
Emulsoids
.05

22. What two common compounds are used together as an antioxidative system?
.05
An enzyme that converts hydrogen peroxide to water plus oxygen.
Ascorbic Acid and Citric Acid
Polyphenol Oxidase

23. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Anomeric
.05
Capsaicin

24. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lipase
HPLC has higher pressure than FPLC
ERH=100 x Aw

25. What are the primary secondary - tertiary - and quaternary structures?
Blue pigment in flowers
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.
Initiation - Propagation - and Termination
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

26. Name 3 physical agents capable of denaturing proteins.
Oil in Water
Olive Green
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Lysine - Arginine - and Histidine

27. What compounds oxidize to form brown color in fruits and vegetables?
Blue pigment in flowers
Pectin Esterase - Polygalacturonase - Pectin Layase
Polyphenols
NaCl (it dissociated to a 2M solution)

28. What enzyme causes hyrolytic rancidity in milk?
Milk
Lamellar; Hexagonal I - II; Cubic
Lipase
Monosodium Glutamate

29. 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?
Onions ( or leeks)
Pectins
.05 M HCL
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.

30. Name 5 proteins with good foaming properties.
Plasmids
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Prolamines
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.

31. What does the acronym NPN stand for?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Thamautin
Non-protein nitrogen
Initiation - Propagation - and Termination

32. Which of the following examples of browning is enzymatic in nature? 1. Browning of sugars as a result of heating 2. Browning of freshly cut surfaces of fruits and vegetables 3. Browning of bread during toasting 4. Browning of potato chips
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Two aldehydes
Browning of freshly cut surfaces of fruits and vegetables.
RNA transcribed to DNA

33. What is the name of the degradation compound of chlorophyll?
Phenophylin
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Monosodium Glutamate

34. What are the three stages of oxidative rancidity?
HPLC has higher pressure than FPLC
Polyphenol Oxidase
It explodes
Initiation - Propagation - and Termination

35. Name the two components that comprise the relaxing factor in muscle fibers.
Sodium bicarbonate generates CO2
Troponins and Tropomyosin
Pectin Esterase
Covalent (strongest) and Hydrophobic (Weakest)

36. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Tryptophan
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Arachidonic Acid
Linoleic Acid

37. What is surimi?
Plasmids
Lipid oxidation
A concentrate of microfibrillar proteins of fish muscle.
2.5

38. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Primary butyric acid also caproic acid.

39. Name 3 factors influencing the consistency of commercial fats.
Racemic Mixture
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Four
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

40. What is the chemical nomenclature for caffeine?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
1 - 3 - 7-trimethylxanthine
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Glycosides of anthocyanidins

41. In genetics What is conjugation?
Phenophylin
DNA transferred by cell to cell contact (bacterial sex).
Phenophylin
Degradation of protein and production of acid from sugar at the same time.

42. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Negative log of the hydrogen concentration (mol/l).
Aspartic Acid and Phenylalanine
Onions ( or leeks)
Erythorbic Acid

43. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Daminozide
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
ERH=100 x Aw

44. Name a commonly used household chemical leavening agent and the gas it generates.
Linoleic Acid
They act as catalysts - speeding the polymerization of acrylamide.
Sodium bicarbonate generates CO2
Blue pigment in flowers

45. Name 3 reasons it is advantageous to obtain enzymes from microorganisms.

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46. What is Ohm's Law and What is Power Equation?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Blue pigment in flowers
Chlocophyllide does not have a phytoltail
V=IR and P=VI or I x I x are

47. Alar is the trade name for what chemical compound?
Emulsoids
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Daminozide
Sweet - Salty - Sour - and Bitter

48. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
HPLC has higher pressure than FPLC
Pheophytin forms
Browning of freshly cut surfaces of fruits and vegetables.

49. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
Glycosides of anthocyanidins
Fructose
Orange Juice

50. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Polyphenol Oxidase
Glycosides of anthocyanidins
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).