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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 chlocophyllide?
Gliadins and Glutenins
Thermus Aqauticus
Chlocophyllide does not have a phytoltail
V=IR and P=VI or I x I x are

2. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
Covalent (strongest) and Hydrophobic (Weakest)
Aspartic Acid and Phenylalanine
D: None of the above

3. 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
D: None of the above
Fat Oxidation
.05 M HCL
.05

4. What is the protein efficiency ratio (PER) of casein?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
2.5
pH 3-5

5. What are two common reducing agents that break disulfide bonds in proteins?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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.
Degradation of protein and production of acid from sugar at the same time.

6. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
pH 3-5
Gliadins and Glutenins
Pectin methylesterase & polygalacturonase

7. What is the name of the degradation compound of chlorophyll?
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.
Sodium bicarbonate generates CO2
Water
Phenophylin

8. Name the three positively charged amino acids.
Tryptophan
Lysine - Arginine - and Histidine
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Phenophylin

9. What is the chemical nomenclature for caffeine?
1 - 3 - 7-trimethylxanthine
Arachidonic Acid
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
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.

10. Waxes are composed of what two basic chemical entities?
Covalent (strongest) and Hydrophobic (Weakest)
Pheophytin forms
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Fatty Acid (Ester linked) to Fatty Alcohol

11. What happens to chlorophyll on heating?
Pheophytin forms
Negative log of the hydrogen concentration (mol/l).
Osmosis
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

12. Name two non-enzymatic browning reactions.
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.
Linoleic Acid
Carmelization and Maillard
.05

13. Name 3 factors influencing the consistency of commercial fats.
Sodium bicarbonate generates CO2
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
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

14. 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
Lysine - Arginine - and Histidine
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.
Thermus Aqauticus

15. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Pectins
Pheophytia does not have magnesium in porphyrin ring.
A concentrate of microfibrillar proteins of fish muscle.
Daminozide

16. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Plasmids
Bright green
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
RNA transcribed to DNA

17. 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)
2.5
Blue pigment in flowers
Carmelization and Maillard

18. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Pectin Esterase - Polygalacturonase - Pectin Layase
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

19. What are colloids that are stabilized by a layer of solvation called?
Emulsoids
Two aldehydes
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Tryptophan

20. What are the three main steps in the autooxidation of lipids?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
20 carbons and 4 double bonds
Lipid oxidation
Initiation - Propagation - Termination

21. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Two aldehydes
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

22. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
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
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
It explodes
Fat Oxidation

23. At low water activity What is the main deteriorative concern?
Sodium bicarbonate generates CO2
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
The speed of a molecule is proportional to the surrounding voltage gradient.
Lipid oxidation

24. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Negative log of the hydrogen concentration (mol/l).
Olive Green
Bitter

25. When heated ammonium bicarbonate decomposes to form what end products?
Yellow
Oil in Water
Ammonia - Water - Carbon Dioxide
Water

26. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Degradation of protein and production of acid from sugar at the same time.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

27. Name the two components that comprise the relaxing factor in muscle fibers.
Pectin methyl esterase or galacturonase
Tryptophan
Troponins and Tropomyosin
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

28. When heated ammonium bicarbonate decomposes to form what end products?
Lipid oxidation
Whole Milk
Ammonia - Water - Carbon Dioxide
Nucleation or crystal formation and crystal growth.

29. Name three nonpolar polar - and charged amino acids.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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.
Speed of Light
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

30. What is a polymorphism?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Glycosides of anthocyanidins
NaCl (it dissociated to a 2M solution)
Two aldehydes

31. Name 4 advantages of using enzymes in food processing.
V=IR and P=VI or I x I x are
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
Initiation - Propagation - Termination
A concentrate of microfibrillar proteins of fish muscle.

32. What does Acid Degree Value measure and how is it measured?
Emulsification
Emulsoids
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Parabens

33. What is the enzyme that softens tomatoes?
Pectin Esterase
Emulsification
A concentrate of microfibrillar proteins of fish muscle.
Phenylketonuria

34. Alar is the trade name for what chemical compound?
Degradation of protein and production of acid from sugar at the same time.
Plasmids
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Daminozide

35. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
pH below positive charge; pH at no charge; pH above negative charge
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

36. What are the only phenols approved for use in the microbiological preservation of foods?
20 carbons and 4 double bonds
Acetoin
Pectin methylesterase & polygalacturonase
Parabens

37. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Orange Juice
They act as catalysts - speeding the polymerization of acrylamide.
A concentrate of microfibrillar proteins of fish muscle.
Bitter

38. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Two aldehydes
Polyphenoloxidase
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

39. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Bitter
Water
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Glycosides of anthocyanidins

40. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Pectins
Lamellar; Hexagonal I - II; Cubic
Covalent (strongest) and Hydrophobic (Weakest)
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

41. Name one way foam stability can be assessed.
Pectin Esterase
Bitter
Tryptophan
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.

42. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Tryptophan
Phenylketonuria
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Carrageenan

43. At what pH is benzoic acid most effective?
Racemic Mixture
They act as catalysts - speeding the polymerization of acrylamide.
pH 3-5
Initiation - Propagation - Termination

44. Is a disaccharide
Capsaicin
Sucrose
Capsaicin
Oil in Water

45. How many carbon atoms and how many double bonds are there in arachidonic acid?
Phenylketonuria
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
20 carbons and 4 double bonds
Primary butyric acid also caproic acid.

46. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Gossypol (it is removed during the oil refining process)
pH below positive charge; pH at no charge; pH above negative charge
The speed of a molecule is proportional to the surrounding voltage gradient.
NaCl (it dissociated to a 2M solution)

47. Will lipid oxidation be higher at a water activity of .05 or .5?
It explodes
Fatty Acid and Alcohol
No
.05

48. 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?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Blue pigment in flowers
Bright green
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

49. Alar is the trade name for what chemical compound?
Fructose
Fat Oxidation
Lycopenes
Daminozide

50. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Primary butyric acid also caproic acid.
Phenylketonuria
Lamellar; Hexagonal I - II; Cubic
Thamautin