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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 is the structural difference between chlorophyll and pheophytia?
Fatty Acid (Ester linked) to Fatty Alcohol
Pheophytia does not have magnesium in porphyrin ring.
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

2. What ketohexose is most significant to food chemists?
Initiation - Propagation - and Termination
Lipid oxidation
Pectin methylesterase & polygalacturonase
Fructose

3. What is the name of the degradation compound of chlorophyll?
Phenophylin
Lysine - Arginine - and Histidine
HPLC has higher pressure than FPLC
Fatty Acid and Alcohol

4. What are the three main steps in the autooxidation of lipids?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Degradation of protein and production of acid from sugar at the same time.
Erythorbic Acid
Initiation - Propagation - Termination

5. What is acid proteolysis?
Sucrose
Degradation of protein and production of acid from sugar at the same time.
Daminozide
Pectin Esterase

6. 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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Phenophylin
Plasmids
Pectin Esterase - Polygalacturonase - Pectin Layase

7. At low water activity What is the main deteriorative concern?
Linoleic Acid
Lipid oxidation
Pectin Esterase - Polygalacturonase - Pectin Layase
Chlocophyllide does not have a phytoltail

8. In the enzyme Taq Polymerase What does Taq stand for?
Browning of freshly cut surfaces of fruits and vegetables.
Pheophytin forms
Thermus Aqauticus
Emulsification

9. What are the limiting amino acids in corn - potato - and green peas?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Pectins
Speed of Light

10. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Capsaicin
Emulsification
Covalent (strongest) and Hydrophobic (Weakest)
Water

11. Name one way foam stability can be assessed.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
An enzyme that converts hydrogen peroxide to water plus oxygen.
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.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

12. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Acetoin
Olive Green
pH below positive charge; pH at no charge; pH above negative charge
Speed of Light

13. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Sodium bicarbonate generates CO2
Two aldehydes
2.5

14. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Tryptophan
Orange Juice
Blue pigment in flowers
The speed of a molecule is proportional to the surrounding voltage gradient.

15. What are the three main steps in the autooxidation of lipids?
Plasmids
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Sodium bicarbonate generates CO2
Initiation - Propagation - Termination

16. What does HLB stand for and What does a high and low HLB value indicate?
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.
Initiation - Propagation - Termination
Cis
Phenophylin

17. What two types of compounds are joined with an ester bond to make a wax?
Nucleation or crystal formation and crystal growth.
Fatty Acid and Alcohol
Pheophytin forms
Troponins and Tropomyosin

18. At what pH is benzoic acid most effective?
Pheophytin forms
1 - 3 - 7-trimethylxanthine
.05 M HCL
pH 3-5

19. How many carbon atoms are there in the fatty acid myristic acid?
Degradation of protein and production of acid from sugar at the same time.
14
1 - 3 - 7-trimethylxanthine
Speed of Light

20. What enzyme causes hyrolytic rancidity in milk?
20 carbons and 4 double bonds
Lipase
HPLC has higher pressure than FPLC
Aspartic Acid and Phenylalanine

21. What does the iodine value measure and how is it measured?
Tryptophan
Gliadins and Glutenins
Pectin methylesterase & polygalacturonase
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

22. What effect would the addition of sodium bicarbonate have to chocolate?
Lycopenes
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).
Pheophytin forms

23. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Capsaicin
Four
Pectin methylesterase & polygalacturonase
Polyphenoloxidase

24. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Whole Milk
It explodes
Plasmids
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

25. Name two enzymes that are involved in softening fruits.
.05 M HCL
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Pectin Esterase - Polygalacturonase - Pectin Layase
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

26. What two enzymes degrade pectic substances?
Pectin methylesterase & polygalacturonase
Carmelization and Maillard
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Sodium bicarbonate generates CO2

27. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
Bright green
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Anthocyanins

28. Name the strongest biochemical bond and the weakest biochemical bond.
Racemic Mixture
Covalent (strongest) and Hydrophobic (Weakest)
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
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.

29. What is the name given to a mixture of equal parts of Darel Lisomers?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Racemic Mixture
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Initiation - Propagation - and Termination

30. What is Ohm's Law and What is Power Equation?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Sucrose
V=IR and P=VI or I x I x are
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

31. In the enzyme Taq Polymerase What does Taq stand for?
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.
1 - 3 - 7-trimethylxanthine
Thermus Aqauticus
Acetoin

32. Name two reasons why fats are hydrogenated.
Yes
The speed of a molecule is proportional to the surrounding voltage gradient.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Orange Juice

33. Alar is the trade name for what chemical compound?
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.
Daminozide
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Blue pigment in flowers

34. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Chlocophyllide does not have a phytoltail
Polyphenol Oxidase
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

35. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Capsaicin
No
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

36. What is the structural difference between chlorophyll and pheophytia?
Initiation - Propagation - and Termination
Polyphenoloxidase
Pheophytia does not have magnesium in porphyrin ring.
Pectins

37. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
Negative log of the hydrogen concentration (mol/l).
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
RNA transcribed to DNA
Fatty Acid and Alcohol

38. What are proteins which are soluble in 50-80% ethanol known as?
Initiation - Propagation - and Termination
Bright green
Prolamines
Glycosides of anthocyanidins

39. What pigment was first designated as anthocyanins?
Chitin
Four
Blue pigment in flowers
Pectins

40. Are sorbitol and mannitol sweet?
Yes
Negative log of the hydrogen concentration (mol/l).
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Blue pigment in flowers

41. Name two reasons why fats are hydrogenated.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Polyphenols
Oil in Water

42. What are the limiting amino acids in corn - potato - and green peas?
Whole Milk
Emulsoids
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Oil in Water

43. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Thamautin
Orange Juice
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

44. 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)
45% - 52% - 90%
Chitin
Prolamines

45. Name 4 advantages of using enzymes in food processing.
Oil in Water
Pectin methyl esterase or galacturonase
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

46. What enzyme is most responsible for browning bananas?
Daminozide
A concentrate of microfibrillar proteins of fish muscle.
Lipase
Polyphenol Oxidase

47. Contains the lowest content of water
Sucrose
Whole Milk
Primary butyric acid also caproic acid.
Fat Oxidation

48. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
Emulsification
Pectin methylesterase & polygalacturonase
Erythorbic Acid

49. What is a polymorphism?
Degradation of protein and production of acid from sugar at the same time.
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.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

50. Name 5 proteins with good foaming properties.
A concentrate of microfibrillar proteins of fish muscle.
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.
Phenylketonuria
Lycopenes