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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. Alar is the trade name for what chemical compound?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Daminozide
Sodium bicarbonate generates CO2
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

2. What metabolic end product does the Voges-Proskauer test detect?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Acetoin
No
Chlocophyllide does not have a phytoltail

3. What is the structural difference between chlorophyll and pheophytia?
Daminozide
Pheophytia does not have magnesium in porphyrin ring.
Sucrose
Polyphenoloxidase

4. At what pH is benzoic acid most effective?
Polyphenoloxidase
pH 3-5
Lycopenes
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.

5. What is the protein efficiency ratio (PER) of casein?
Racemic Mixture
2.5
Plasmids
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

6. What is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
Onions ( or leeks)
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
An enzyme that converts hydrogen peroxide to water plus oxygen.

7. 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
.05 M HCL
Browning of freshly cut surfaces of fruits and vegetables.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Racemic Mixture

8. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Thermus Aqauticus
Daminozide
Initiation - Propagation - and Termination

9. How can a molecular weight of protein - DNA - and RNA be determined?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Polyphenol Oxidase
V=IR and P=VI or I x I x are
.05

10. What are 3 mesomorphic structures associated with lipids in the liquid state?
Lamellar; Hexagonal I - II; Cubic
.05
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Linoleic Acid

11. What does the acronym NPN stand for?
Acetoin
Gossypol (it is removed during the oil refining process)
Non-protein nitrogen
Yes

12. Name two reasons why fats are hydrogenated.
Polyphenol Oxidase
Plasmids
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
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

13. What are the only phenols approved for use in the microbiological preservation of foods?
Anthocyanins
Racemic Mixture
ERH=100 x Aw
Parabens

14. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Carmelization and Maillard
pH below positive charge; pH at no charge; pH above negative charge
They act as catalysts - speeding the polymerization of acrylamide.
ERH=100 x Aw

15. What enzyme is most responsible for browning bananas?
Gossypol (it is removed during the oil refining process)
14
Polyphenol Oxidase
Monosodium Glutamate

16. How many carbon atoms and how many double bonds are there in arachidonic acid?
Pheophytin forms
Daminozide
20 carbons and 4 double bonds
Phenophylin

17. Name 3 factors influencing the consistency of commercial fats.
Pectin Esterase
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
.05
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

18. Are sorbitol and mannitol sweet?
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Negative log of the hydrogen concentration (mol/l).
Prolamines
Yes

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

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20. During freezing What are the two stages in the crystallization process?
Nucleation or crystal formation and crystal growth.
Carmelization and Maillard
Four
Oil in Water

21. What are the only phenols approved for use in the microbiological preservation of foods?
14
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
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
Parabens

22. What compounds oxidize to form brown color in fruits and vegetables?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Covalent (strongest) and Hydrophobic (Weakest)
Polyphenols
Capsaicin

23. What is the major color compound in tomatoes?
Lycopenes
Pectins
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.
They act as catalysts - speeding the polymerization of acrylamide.

24. What is the name of the degradation compound of chlorophyll?
Phenophylin
D: None of the above
Pectin methyl esterase or galacturonase
Yes

25. Contains the lowest content of water
Whole Milk
Milk
Fructose
Pheophytia does not have magnesium in porphyrin ring.

26. Name two non-enzymatic browning reactions.
Bright green
D: None of the above
Browning of freshly cut surfaces of fruits and vegetables.
Carmelization and Maillard

27. Give one word for a carbon atom involved in hemiacetal or acetal formation.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Anomeric
It explodes

28. 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
Ascorbic Acid and Citric Acid
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
D: None of the above
Bitter

29. What is the enzyme that softens tomatoes?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Pectin Esterase
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.
Milk

30. Name the three positively charged amino acids.
Pheophytia does not have magnesium in porphyrin ring.
No
Lysine - Arginine - and Histidine
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

31. What is a polymorphism?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
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.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

32. What is an isomer that is cheaper than Vitamin C?
Non-protein nitrogen
Erythorbic Acid
RNA transcribed to DNA
Blue pigment in flowers

33. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
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
Two aldehydes
Lipid oxidation

34. 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
Two aldehydes
Chitin
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

35. In genetics What is conjugation?
Lipid oxidation
Olive Green
DNA transferred by cell to cell contact (bacterial sex).
Glycosides of anthocyanidins

36. At low water activity What is the main deteriorative concern?
Lipid oxidation
No
A concentrate of microfibrillar proteins of fish muscle.
1 - 3 - 7-trimethylxanthine

37. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Pectin Esterase - Polygalacturonase - Pectin Layase
Arachidonic Acid

38. Name the strongest biochemical bond and the weakest biochemical bond.
Emulsoids
Pheophytia does not have magnesium in porphyrin ring.
Covalent (strongest) and Hydrophobic (Weakest)
Bright green

39. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Onions ( or leeks)
Olive Green
Cis

40. 20 grams of amylose is added to 80 grams of water in a bearker; the boiling point is measured with an ordinary mercury-in-glass thermometer. What is the observed boiling point of the material in the beaker?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Degradation of protein and production of acid from sugar at the same time.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Acsulfame-K - Saccharin - Cyclamate - Aspartame

41. What is the chemical nomenclature for caffeine?
1 - 3 - 7-trimethylxanthine
Thermus Aqauticus
Erythorbic Acid
D: None of the above

42. In what food is butyric acid typically found?
Milk
Oil in Water
Aspartic Acid and Phenylalanine
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

43. What are two common reducing agents that break disulfide bonds in proteins?
V=IR and P=VI or I x I x are
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
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Prolamines

44. 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
Yes
45% - 52% - 90%
D: None of the above
Glycosides of anthocyanidins

45. How do sodium chloride and sucrose affect foam stability?
Ammonia - Water - Carbon Dioxide
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.
RNA transcribed to DNA
Sodium chloride reduces foam stability and sucrose improves foam stability.

46. Alar is the trade name for what chemical compound?
Lamellar; Hexagonal I - II; Cubic
Daminozide
Bitter
Lycopenes

47. What is the name given to a mixture of equal parts of Darel Lisomers?
Blue pigment in flowers
Racemic Mixture
Initiation - Propagation - Termination
Oil in Water

48. In what food is butyric acid typically found?
Cis
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Milk
Sucrose

49. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Pheophytin forms
Pectin methylesterase & polygalacturonase
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.

50. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Tryptophan