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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?
Carrageenan
Pheophytia does not have magnesium in porphyrin ring.
Cis
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

2. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
Fatty Acid (Ester linked) to Fatty Alcohol
Thamautin
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.

3. What are the three main steps in the autooxidation of lipids?
Fatty Acid (Ester linked) to Fatty Alcohol
Chitin
Negative log of the hydrogen concentration (mol/l).
Initiation - Propagation - Termination

4. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
.05 M HCL
Oil in Water
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

5. What enzyme causes hyrolytic rancidity in milk?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
HPLC has higher pressure than FPLC
Carmelization and Maillard
Lipase

6. What is the protein efficiency ratio (PER) of casein?
Monosodium Glutamate
Bitter
Acetoin
2.5

7. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Anomeric

8. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
Sucrose
Primary butyric acid also caproic 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

9. Contains the lowest content of water
Linoleic Acid
Orange Juice
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Whole Milk

10. What happens to chlorophyll on heating?
Pheophytin forms
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
RNA transcribed to DNA

11. How many carbon atoms are there in the fatty acid myristic acid?
Polyphenols
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.
Anthocyanins
14

12. What are the four basic flavors perceived by the tongue?
Pectin methylesterase & polygalacturonase
Sweet - Salty - Sour - and Bitter
Plasmids
Lycopenes

13. What does the saponification value measure and how is it measured?
Thickener in foods
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.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

14. What is catalase?
Linoleic Acid
An enzyme that converts hydrogen peroxide to water plus oxygen.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
NaCl (it dissociated to a 2M solution)

15. What is the acid present in fish oil?
Anthocyanins
Polyphenols
Tryptophan
Arachidonic Acid

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

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17. 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
Daminozide
Troponins and Tropomyosin
Carrageenan
D: None of the above

18. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Thermus Aqauticus
Water
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.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

19. What is the winterization process for an oil?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Four
20 carbons and 4 double bonds
V=IR and P=VI or I x I x are

20. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
RNA transcribed to DNA
Covalent (strongest) and Hydrophobic (Weakest)
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Initiation - Propagation - Termination

21. What are the three stages of oxidative rancidity?
Plasmids
A concentrate of microfibrillar proteins of fish muscle.
Initiation - Propagation - and Termination
Primary butyric acid also caproic acid.

22. Name three factors useful in controlling enzyme activity.
V=IR and P=VI or I x I x are
Carrageenan
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

23. At low water activity What is the main deteriorative concern?
Sucrose
No
Lipid oxidation
Four

24. Is a disaccharide
The speed of a molecule is proportional to the surrounding voltage gradient.
Covalent (strongest) and Hydrophobic (Weakest)
Parabens
Sucrose

25. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Water
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Ascorbic Acid and Citric Acid
Linoleic Acid

26. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Polyphenols
pH 3-5
Linoleic Acid
Phenylketonuria

27. 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)
Lamellar; Hexagonal I - II; Cubic
HPLC has higher pressure than FPLC
Four

28. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Orange Juice
Nucleation or crystal formation and crystal growth.
Olive Green
Negative log of the hydrogen concentration (mol/l).

29. What are two common reducing agents that break disulfide bonds in proteins?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
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)
Lysine - Arginine - and Histidine

30. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
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.
Polyphenols
No

31. What two types of compounds are joined with an ester bond to make a wax?
pH 3-5
Polyphenoloxidase
Fatty Acid and Alcohol
Pectin Esterase

32. Name the two components that comprise the relaxing factor in muscle fibers.
Troponins and Tropomyosin
Emulsification
Lycopenes
pH below positive charge; pH at no charge; pH above negative charge

33. When heated ammonium bicarbonate decomposes to form what end products?
Lysine - Arginine - and Histidine
Yellow
Ammonia - Water - Carbon Dioxide
Plasmids

34. What does the saponification value measure and how is it measured?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Lipid oxidation
Fatty Acid and Alcohol

35. At what pH is benzoic acid most effective?
pH 3-5
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Polyphenols
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

36. How do sodium chloride and sucrose affect foam stability?
Pectin methylesterase & polygalacturonase
D: None of the above
Initiation - Propagation - and Termination
Sodium chloride reduces foam stability and sucrose improves foam stability.

37. What compounds oxidize to form brown color in fruits and vegetables?
Polyphenols
Thickener in foods
Thamautin
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

38. Name 3 physical agents capable of denaturing proteins.
Thermus Aqauticus
.05
Parabens
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

39. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Onions ( or leeks)
HPLC has higher pressure than FPLC
Chitin
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

40. How many carbon atoms are there in the fatty acid myristic acid?
14
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Two aldehydes
1 - 3 - 7-trimethylxanthine

41. Name the three positively charged amino acids.
ERH=100 x Aw
Parabens
Pheophytin forms
Lysine - Arginine - and Histidine

42. Name the two components that comprise the relaxing factor in muscle fibers.
Pectin methylesterase & polygalacturonase
Troponins and Tropomyosin
Phenylketonuria
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

43. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Initiation - Propagation - and Termination
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Parabens
Capsaicin

44. How does ERH relate to water activity?
ERH=100 x Aw
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
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.

45. 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?
Plasmids
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Polyphenol Oxidase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

46. What pigment was first designated as anthocyanins?
Glycosides of anthocyanidins
Blue pigment in flowers
Emulsification
Carmelization and Maillard

47. What are the three main steps in the autooxidation of lipids?
Polyphenol Oxidase
Initiation - Propagation - Termination
Parabens
pH below positive charge; pH at no charge; pH above negative charge

48. Name 3 chemical agents capable of denaturing proteins.
Sweet - Salty - Sour - and Bitter
Lipase
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
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.

49. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
20 carbons and 4 double bonds
Primary butyric acid also caproic acid.
Plasmids
Lycopenes

50. What enzyme is most responsible for browning bananas?
NaCl (it dissociated to a 2M solution)
Polyphenol Oxidase
Sweet - Salty - Sour - and Bitter
Lipid oxidation