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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. Which two amino acids is the aspartame derived from?
Racemic Mixture
Aspartic Acid and Phenylalanine
Parabens
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

2. What effect would the addition of sodium bicarbonate have to chocolate?
45% - 52% - 90%
Four
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Four

3. Name 3 chemical agents capable of denaturing proteins.
The speed of a molecule is proportional to the surrounding voltage gradient.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
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. What two types of compounds are joined with an ester bond to make a wax?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
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.
Fatty Acid and Alcohol
NaCl (it dissociated to a 2M solution)

5. Is a disaccharide
Yellow
Sucrose
Polyphenol Oxidase
Chlocophyllide does not have a phytoltail

6. Name 3 physical agents capable of denaturing proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
.05
Sucrose
Lycopenes

7. How is pH defined?
Negative log of the hydrogen concentration (mol/l).
Primary butyric acid also caproic acid.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Fat Oxidation

8. Name one way foam stability can be assessed.
Speed of Light
Sodium bicarbonate generates CO2
Primary butyric acid also caproic acid.
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.

9. In the enzyme Taq Polymerase What does Taq stand for?
Thermus Aqauticus
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
1 - 3 - 7-trimethylxanthine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

10. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Ascorbic Acid and Citric Acid
Linoleic Acid
No
Carrageenan

11. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
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.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Phenophylin
Orange Juice

12. Name 3 factors influencing the consistency of commercial fats.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Thermus Aqauticus
Primary butyric acid also caproic acid.

13. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
HPLC has higher pressure than FPLC
45% - 52% - 90%
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

14. What are the four basic flavors perceived by the tongue?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Emulsoids
Sweet - Salty - Sour - and Bitter
Covalent (strongest) and Hydrophobic (Weakest)

15. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Sucrose
Phenylketonuria
NaCl (it dissociated to a 2M solution)
Sweet - Salty - Sour - and Bitter

16. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
Yellow
Monosodium Glutamate
Sodium bicarbonate generates CO2

17. What is Ohm's Law and What is Power Equation?
pH 3-5
V=IR and P=VI or I x I x are
14
Browning of freshly cut surfaces of fruits and vegetables.

18. Alar is the trade name for what chemical compound?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
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).
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

19. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Erythorbic Acid
Thickener in foods
.05 M HCL
Yellow

20. What is the acid present in fish oil?
Acetoin
pH below positive charge; pH at no charge; pH above negative charge
Arachidonic Acid
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

21. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Thickener in foods
Initiation - Propagation - and Termination
Plasmids
Pectin methyl esterase or galacturonase

22. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
DNA transferred by cell to cell contact (bacterial sex).
Covalent (strongest) and Hydrophobic (Weakest)
Osmosis

23. How many carbon atoms are there in the fatty acid myristic acid?
Thickener in foods
14
Linoleic Acid
Primary butyric acid also caproic acid.

24. What enzyme causes hyrolytic rancidity in milk?
Lipase
Yes
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Emulsoids

25. Will lipid oxidation be higher at a water activity of .05 or .5?
Anthocyanins
No
.05
Pectin methyl esterase or galacturonase

26. During freezing What are the two stages in the crystallization process?
Aspartic Acid and Phenylalanine
Nucleation or crystal formation and crystal growth.
Acetoin
Carmelization and Maillard

27. What is Carboxy-methyl cellulose often used for?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Thickener in foods
Osmosis
Polyphenoloxidase

28. What is the chemical nature of anthocyanins?
Polyphenol Oxidase
Sodium chloride reduces foam stability and sucrose improves foam stability.
Glycosides of anthocyanidins
RNA transcribed to DNA

29. What two common compounds are used together as an antioxidative system?
Onions ( or leeks)
Ascorbic Acid and Citric Acid
Oil in Water
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

30. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
pH 3-5
Plasmids
14
Onions ( or leeks)

31. What is the Peroxide Value a measure of?
Fat Oxidation
Aspartic Acid and Phenylalanine
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Yes

32. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
Lipid oxidation
RNA transcribed to DNA
Arachidonic Acid
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.

33. What is Ohm's Law and What is Power Equation?
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.
V=IR and P=VI or I x I x are
Troponins and Tropomyosin
Nucleation or crystal formation and crystal growth.

34. What does the iodine value measure and how is it measured?
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.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
V=IR and P=VI or I x I x are
Osmosis

35. At low water activity What is the main deteriorative concern?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Lipid oxidation
Olive Green
Osmosis

36. What is the main class of color compounds found in raspberries?
Anthocyanins
V=IR and P=VI or I x I x are
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.
Chitin

37. What is surimi?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
A concentrate of microfibrillar proteins of fish muscle.
Glycosides of anthocyanidins
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

38. What is the structural difference between chlorophyll and pheophytia?
Lipase
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Gossypol (it is removed during the oil refining process)
Pheophytia does not have magnesium in porphyrin ring.

39. What does Acid Degree Value measure and how is it measured?
DNA transferred by cell to cell contact (bacterial sex).
Browning of freshly cut surfaces of fruits and vegetables.
20 carbons and 4 double bonds
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

40. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Polyphenol Oxidase
It explodes
NaCl (it dissociated to a 2M solution)

41. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Thickener in foods
Aspartic Acid and Phenylalanine
Chitin
Daminozide

42. What compounds oxidize to form brown color in fruits and vegetables?
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
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.
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.
Polyphenols

43. What does the saponification value measure and how is it measured?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Initiation - Propagation - and Termination
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
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.

44. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Chitin
Acetoin
Arachidonic Acid
Sodium chloride reduces foam stability and sucrose improves foam stability.

45. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Negative log of the hydrogen concentration (mol/l).
Negative log of the hydrogen concentration (mol/l).
Onions ( or leeks)

46. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Oil in Water
HPLC has higher pressure than FPLC
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.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

47. What are 3 mesomorphic structures associated with lipids in the liquid state?
Lamellar; Hexagonal I - II; Cubic
NaCl (it dissociated to a 2M solution)
Arachidonic Acid
Bright green

48. Will lipid oxidation be higher at a water activity of .05 or .5?
Aspartic Acid and Phenylalanine
Covalent (strongest) and Hydrophobic (Weakest)
.05
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

49. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Pheophytin forms
D: None of the above
Linoleic Acid
Degradation of protein and production of acid from sugar at the same time.

50. What is the major color compound in tomatoes?
Primary butyric acid also caproic acid.
Lycopenes
It explodes
Oil in Water