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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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This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What pigment was first designated as anthocyanins?
Water
V=IR and P=VI or I x I x are
Erythorbic Acid
Blue pigment in flowers

2. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
Nucleation or crystal formation and crystal growth.
1 - 3 - 7-trimethylxanthine
Speed of Light

3. What ketohexose is most significant to food chemists?
Fructose
Sodium bicarbonate generates CO2
45% - 52% - 90%
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

4. What two types of compounds are joined with an ester bond to make a wax?
Troponins and Tropomyosin
Milk
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Fatty Acid and Alcohol

5. How does ERH relate to water activity?
Emulsoids
Olive Green
ERH=100 x Aw
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

6. What does HLB stand for and What does a high and low HLB value indicate?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Arachidonic Acid
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.
1 - 3 - 7-trimethylxanthine

7. Name two enzymes that are involved in softening fruits.
1 - 3 - 7-trimethylxanthine
Thermus Aqauticus
DNA transferred by cell to cell contact (bacterial sex).
Pectin Esterase - Polygalacturonase - Pectin Layase

8. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
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.
Olive Green
Daminozide

9. Name the two components that comprise the relaxing factor in muscle fibers.
Troponins and Tropomyosin
Sodium bicarbonate generates CO2
Tryptophan
Sodium chloride reduces foam stability and sucrose improves foam stability.

10. What is the major color compound in tomatoes?
V=IR and P=VI or I x I x are
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Lycopenes
Cis

11. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Water
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

12. What enzyme is most responsible for browning bananas?
Polyphenol Oxidase
A concentrate of microfibrillar proteins of fish muscle.
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
Initiation - Propagation - and Termination

13. 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
Polyphenols
Initiation - Propagation - Termination
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
pH 3-5

14. In what food is butyric acid typically found?
Erythorbic Acid
Negative log of the hydrogen concentration (mol/l).
Milk
RNA transcribed to DNA

15. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
RNA transcribed to DNA
Fat Oxidation
A concentrate of microfibrillar proteins of fish muscle.
Bright green

16. How is pH defined?
Negative log of the hydrogen concentration (mol/l).
Bright green
pH 3-5
The speed of a molecule is proportional to the surrounding voltage gradient.

17. Peptide bond formation results in the formation of what secondary compound?
The speed of a molecule is proportional to the surrounding voltage gradient.
Water
HPLC has higher pressure than FPLC
Carrageenan

18. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Degradation of protein and production of acid from sugar at the same time.
Linoleic Acid
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Daminozide

19. How many carbon atoms and how many double bonds are there in arachidonic acid?
20 carbons and 4 double bonds
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Phenophylin
Nucleation or crystal formation and crystal growth.

20. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Ascorbic Acid and Citric Acid
Aspartic Acid and Phenylalanine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

21. What is the acid present in fish oil?
Plasmids
Arachidonic Acid
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
NaCl (it dissociated to a 2M solution)

22. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Covalent (strongest) and Hydrophobic (Weakest)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Racemic Mixture
They act as catalysts - speeding the polymerization of acrylamide.

23. What enzyme causes hyrolytic rancidity in milk?
Pectin Esterase
An enzyme that converts hydrogen peroxide to water plus oxygen.
pH below positive charge; pH at no charge; pH above negative charge
Lipase

24. Does kosmotrophil ion discourage water structure?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Initiation - Propagation - Termination
No
Emulsoids

25. Are sorbitol and mannitol sweet?
Yes
Pheophytia does not have magnesium in porphyrin ring.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Olive Green

26. 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?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Capsaicin
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

27. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
Daminozide
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Lipase

28. 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
Two aldehydes
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.
Browning of freshly cut surfaces of fruits and vegetables.
Gliadins and Glutenins

29. In what food is butyric acid typically found?
Fatty Acid and Alcohol
Milk
pH below positive charge; pH at no charge; pH above negative charge
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.

30. What enzyme is most responsible for browning bananas?
Water
Chitin
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Polyphenol Oxidase

31. What is the enzyme that softens tomatoes?
NaCl (it dissociated to a 2M solution)
Pectin Esterase
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Carmelization and Maillard

32. What is catalase?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Capsaicin
.05 M HCL

33. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
pH 3-5
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Tryptophan

34. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Carrageenan
Polyphenol Oxidase
Osmosis
An enzyme that converts hydrogen peroxide to water plus oxygen.

35. Name the two components that comprise the relaxing factor in muscle fibers.
Bitter
Daminozide
Troponins and Tropomyosin
Chlocophyllide does not have a phytoltail

36. Name 3 physical agents capable of denaturing proteins.
Whole Milk
No
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

37. What are 3 mesomorphic structures associated with lipids in the liquid state?
The speed of a molecule is proportional to the surrounding voltage gradient.
Lamellar; Hexagonal I - II; Cubic
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Anomeric

38. Alar is the trade name for what chemical compound?
Yes
Daminozide
Blue pigment in flowers
NaCl (it dissociated to a 2M solution)

39. What is the name given to a mixture of equal parts of Darel Lisomers?
Gossypol (it is removed during the oil refining process)
Racemic Mixture
Sodium bicarbonate generates CO2
No

40. Name 4 advantages of using enzymes in food processing.
Phenophylin
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
Degradation of protein and production of acid from sugar at the same time.
Chitin

41. What are the limiting amino acids in corn - potato - and green peas?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Bitter
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Phenophylin

42. What is the name of the degradation compound of chlorophyll?
Sucrose
Troponins and Tropomyosin
Pectin methyl esterase or galacturonase
Phenophylin

43. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
Nucleation or crystal formation and crystal growth.
Troponins and Tropomyosin
Pectin methylesterase & polygalacturonase

44. At what pH is benzoic acid most effective?
Yellow
Negative log of the hydrogen concentration (mol/l).
pH 3-5
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

45. How do sodium chloride and sucrose affect foam stability?
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
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Sodium chloride reduces foam stability and sucrose improves foam stability.
Bitter

46. What are the fructose contents in commercial HFCS products.
Pectin Esterase - Polygalacturonase - Pectin Layase
HPLC has higher pressure than FPLC
45% - 52% - 90%
Polyphenoloxidase

47. How does HPLC differ from FPLC?
Phenophylin
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.
HPLC has higher pressure than FPLC
Sodium chloride reduces foam stability and sucrose improves foam stability.

48. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
DNA transferred by cell to cell contact (bacterial sex).
Plasmids
Polyphenol Oxidase
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

49. What is an isomer that is cheaper than Vitamin C?
Erythorbic Acid
Yes
Pectin methyl esterase or galacturonase
Thamautin

50. What is the chemical nature of anthocyanins?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Glycosides of anthocyanidins
Pectin methylesterase & polygalacturonase
Ammonia - Water - Carbon Dioxide