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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 compounds capable of poisoning the catalyst during commercial hydrogenation.
Aspartic Acid and Phenylalanine
HPLC has higher pressure than FPLC
.05 M HCL
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

2. What does HLB stand for and What does a high and low HLB value indicate?
Emulsification
Daminozide
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
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.

3. What is an isomer that is cheaper than Vitamin C?
Daminozide
Erythorbic Acid
Fat Oxidation
Monosodium Glutamate

4. What two common compounds are used together as an antioxidative system?
Sucrose
Monosodium Glutamate
Ascorbic Acid and Citric Acid
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

5. What is the name given to a mixture of equal parts of Darel Lisomers?
Lysine - Arginine - and Histidine
Pheophytia does not have magnesium in porphyrin ring.
Racemic Mixture
Two aldehydes

6. 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
HPLC has higher pressure than FPLC
Whole Milk
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Browning of freshly cut surfaces of fruits and vegetables.

7. What two common compounds are used together as an antioxidative system?
Ascorbic Acid and Citric Acid
.05 M HCL
Fatty Acid and Alcohol
Troponins and Tropomyosin

8. Are sorbitol and mannitol sweet?
Ascorbic Acid and Citric Acid
Covalent (strongest) and Hydrophobic (Weakest)
Two aldehydes
Yes

9. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Browning of freshly cut surfaces of fruits and vegetables.
Gossypol (it is removed during the oil refining process)

10. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Initiation - Propagation - and Termination
Onions ( or leeks)
Cis

11. Name three effects of protein denaturation.
Phenophylin
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Water

12. Name the most common functional property of phospholipids in food systems.
Two aldehydes
Aspartic Acid and Phenylalanine
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Emulsification

13. In the enzyme Taq Polymerase What does Taq stand for?
The speed of a molecule is proportional to the surrounding voltage gradient.
Thermus Aqauticus
Sodium chloride reduces foam stability and sucrose improves foam stability.
They act as catalysts - speeding the polymerization of acrylamide.

14. Name 5 chelating agents used in the food industry.
Lipid oxidation
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Water
.05

15. What enzyme is most responsible for browning bananas?
Polyphenol Oxidase
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Troponins and Tropomyosin
Degradation of protein and production of acid from sugar at the same time.

16. What are soluble polymers of anhydro-galacturonic acid and its esters called?
20 carbons and 4 double bonds
Pectins
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

17. Name three effects of protein denaturation.
Tryptophan
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
NaCl (it dissociated to a 2M solution)
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

18. What is the name of the degradation compound of chlorophyll?
Parabens
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Phenophylin
Lipase

19. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Thermus Aqauticus
Prolamines
Linoleic Acid

20. What ketohexose is most significant to food chemists?
Fructose
Troponins and Tropomyosin
Negative log of the hydrogen concentration (mol/l).
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

21. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
Bitter
Linoleic Acid
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

22. Name the three positively charged amino acids.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Sodium bicarbonate generates CO2
Lysine - Arginine - and Histidine
Pectin methylesterase & polygalacturonase

23. How can a molecular weight of protein - DNA - and RNA be determined?
Pectin methyl esterase or galacturonase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Acetoin
Arachidonic Acid

24. Name three factors useful in controlling enzyme activity.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

25. Name three non-nutritive sweeteners approved for use in USA?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Polyphenol Oxidase
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lycopenes

26. How many carbon atoms and how many double bonds are there in arachidonic acid?
Water
20 carbons and 4 double bonds
Gliadins and Glutenins
Speed of Light

27. Name a naturally occurring protein sweetener.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Thamautin
A concentrate of microfibrillar proteins of fish muscle.
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.

28. What toxic pigment is found in cottonseed endosperm?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Lamellar; Hexagonal I - II; Cubic
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Gossypol (it is removed during the oil refining process)

29. Name two non-enzymatic browning reactions.
Gossypol (it is removed during the oil refining process)
Carmelization and Maillard
pH below positive charge; pH at no charge; pH above negative charge
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

30. What two enzymes degrade pectic substances?
A concentrate of microfibrillar proteins of fish muscle.
Pectin methylesterase & polygalacturonase
.05
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. What does the 'c' stand for in the equation E=mc2?
A concentrate of microfibrillar proteins of fish muscle.
Speed of Light
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
Carrageenan

32. Peptide bond formation results in the formation of what secondary compound?
Pectins
Water
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Degradation of protein and production of acid from sugar at the same time.

33. Name 4 advantages of using enzymes in food processing.
Ascorbic Acid and Citric Acid
Pectin Esterase - Polygalacturonase - Pectin Layase
Speed of Light
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

34. What is the structural difference between chlorophyll and chlocophyllide?
Glycosides of anthocyanidins
Cis
Emulsification
Chlocophyllide does not have a phytoltail

35. At low water activity What is the main deteriorative concern?
Phenylketonuria
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Lipid oxidation
Aspartic Acid and Phenylalanine

36. Name 3 factors influencing the rate of lipid oxidation in foods.
Oil in Water
Browning of freshly cut surfaces of fruits and vegetables.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
An enzyme that converts hydrogen peroxide to water plus oxygen.

37. 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?
.05 M HCL
Lipid oxidation
ERH=100 x Aw
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

38. What are the fructose contents in commercial HFCS products.
Chitin
Oil in Water
Parabens
45% - 52% - 90%

39. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Thermus Aqauticus
Troponins and Tropomyosin
Pectin methyl esterase or galacturonase

40. Alar is the trade name for what chemical compound?
Daminozide
Oil in Water
Phenylketonuria
It explodes

41. Name 4 advantages of using enzymes in food processing.
Cis
Bright green
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
Fat Oxidation

42. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
Water
.05
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

43. Are sorbitol and mannitol sweet?
Yes
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Phenylketonuria
Polyphenol Oxidase

44. What is a polymorphism?
D: None of the above
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Monosodium Glutamate
They act as catalysts - speeding the polymerization of acrylamide.

45. Name 3 physical agents capable of denaturing proteins.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Emulsoids
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Oil in Water

46. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
Polyphenol Oxidase
NaCl (it dissociated to a 2M solution)
Polyphenoloxidase

47. 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
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Pectin Esterase - Polygalacturonase - Pectin Layase
Browning of freshly cut surfaces of fruits and vegetables.
Sodium bicarbonate generates CO2

48. What is the common name for 9 12 - cis-cis-octa dienoic acid?
No
Linoleic Acid
Daminozide
Fat Oxidation

49. Name the most common functional property of phospholipids in food systems.
Emulsification
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Lamellar; Hexagonal I - II; Cubic
Thamautin

50. 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?
It explodes
Polyphenols
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Cis