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Food Chemistry

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1. Name 3 factors influencing the consistency of commercial fats.
Two aldehydes
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Arachidonic Acid
Pectins

2. How many carbon atoms and how many double bonds are there in arachidonic acid?
Pheophytia does not have magnesium in porphyrin ring.
Yellow
20 carbons and 4 double bonds
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

3. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Polyphenols
Pectin methyl esterase or galacturonase
2.5

4. What does the iodine value measure and how is it measured?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
HPLC has higher pressure than FPLC
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Two aldehydes

5. 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?
pH 3-5
Blue pigment in flowers
HPLC has higher pressure than FPLC
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

6. How is pH defined?
Lipase
Ascorbic Acid and Citric Acid
Four
Negative log of the hydrogen concentration (mol/l).

7. Name 3 chemical agents capable of denaturing proteins.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
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
Yes

8. What is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
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).
Sweet - Salty - Sour - and Bitter

9. What are the primary secondary - tertiary - and quaternary structures?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
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.
Monosodium Glutamate

10. At what pH is benzoic acid most effective?
pH 3-5
2.5
Ascorbic Acid and Citric Acid
14

11. Name 5 proteins with good foaming properties.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
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.
Primary butyric acid also caproic acid.
Arachidonic Acid

12. What is the protein efficiency ratio (PER) of casein?
Phenophylin
2.5
No
Polyphenols

13. What is the structural difference between chlorophyll and pheophytia?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pheophytia does not have magnesium in porphyrin ring.
Oil in Water
Pectin Esterase

14. Name 3 physical agents capable of denaturing proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Aspartic Acid and Phenylalanine
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

15. What ketohexose is most significant to food chemists?
Fructose
V=IR and P=VI or I x I x are
14
Non-protein nitrogen

16. What does the 'c' stand for in the equation E=mc2?
Sucrose
Speed of Light
Thamautin
Thickener in foods

17. 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?
Pectin Esterase
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
.05 M HCL
14

18. When heated ammonium bicarbonate decomposes to form what end products?
.05 M HCL
Fructose
Troponins and Tropomyosin
Ammonia - Water - Carbon Dioxide

19. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Thickener in foods
Anthocyanins
Plasmids
Pectin Esterase

20. Name three non-nutritive sweeteners approved for use in USA?
Fatty Acid and Alcohol
Acsulfame-K - Saccharin - Cyclamate - Aspartame
1 - 3 - 7-trimethylxanthine
Negative log of the hydrogen concentration (mol/l).

21. What is surimi?
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Negative log of the hydrogen concentration (mol/l).
A concentrate of microfibrillar proteins of fish muscle.
Ascorbic Acid and Citric Acid

22. At low water activity What is the main deteriorative concern?
Lipid oxidation
Sweet - Salty - Sour - and Bitter
Anomeric
Daminozide

23. 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
A concentrate of microfibrillar proteins of fish muscle.
Onions ( or leeks)
Browning of freshly cut surfaces of fruits and vegetables.
Emulsoids

24. What compounds oxidize to form brown color in fruits and vegetables?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Water
Pectin methyl esterase or galacturonase
Polyphenols

25. What are 3 mesomorphic structures associated with lipids in the liquid state?
Tryptophan
Pheophytin forms
Emulsification
Lamellar; Hexagonal I - II; Cubic

26. Name the two components that comprise the relaxing factor in muscle fibers.
Polyphenoloxidase
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Sucrose
Troponins and Tropomyosin

27. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
They act as catalysts - speeding the polymerization of acrylamide.
Osmosis
Aspartic Acid and Phenylalanine
Racemic Mixture

28. Name three factors useful in controlling enzyme activity.
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.
Capsaicin
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
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.

29. What does Reichert-Meissert Number measure?
Onions ( or leeks)
Polyphenol Oxidase
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.

30. What pigment was first designated as anthocyanins?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Pectin methylesterase & polygalacturonase
Blue pigment in flowers

31. What is acid proteolysis?
Degradation of protein and production of acid from sugar at the same time.
Pectin Esterase
Onions ( or leeks)
Olive Green

32. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Browning of freshly cut surfaces of fruits and vegetables.
Osmosis
2.5
Nucleation or crystal formation and crystal growth.

33. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Chlocophyllide does not have a phytoltail
Osmosis
Chlocophyllide does not have a phytoltail
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

34. What does Acid Degree Value measure and how is it measured?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Carrageenan
Cis
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

35. How can a molecular weight of protein - DNA - and RNA be determined?
pH 3-5
Tryptophan
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Monosodium Glutamate

36. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Chitin
Four
Ascorbic Acid and Citric Acid

37. Name two non-enzymatic browning reactions.
V=IR and P=VI or I x I x are
Carmelization and Maillard
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.
Prolamines

38. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Nucleation or crystal formation and crystal growth.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
They act as catalysts - speeding the polymerization of acrylamide.

39. Name three nonpolar polar - and charged amino acids.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Fat Oxidation
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Polyphenoloxidase

40. Name 3 factors influencing the rate of lipid oxidation in foods.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Yellow
Lamellar; Hexagonal I - II; Cubic
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

41. Will lipid oxidation be higher at a water activity of .05 or .5?
HPLC has higher pressure than FPLC
Blue pigment in flowers
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
.05

42. Is a disaccharide
Sucrose
Polyphenols
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.
Fructose

43. Name the strongest biochemical bond and the weakest biochemical bond.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Covalent (strongest) and Hydrophobic (Weakest)
Emulsification
Fatty Acid (Ester linked) to Fatty Alcohol

44. What is the geometric configuration of double bonds in most natural fatty acids?
DNA transferred by cell to cell contact (bacterial sex).
Carmelization and Maillard
Cis
Pectin Esterase - Polygalacturonase - Pectin Layase

45. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
Covalent (strongest) and Hydrophobic (Weakest)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
pH 3-5

46. What is the enzyme responsible for browning in apples and lettuce?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Polyphenol Oxidase
Arachidonic Acid
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

47. What is the name given to a mixture of equal parts of Darel Lisomers?
Two aldehydes
Racemic Mixture
Sucrose
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

48. What is the chemical nomenclature for caffeine?
Chlocophyllide does not have a phytoltail
Initiation - Propagation - Termination
They act as catalysts - speeding the polymerization of acrylamide.
1 - 3 - 7-trimethylxanthine

49. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
NaCl (it dissociated to a 2M solution)
Acsulfame-K - Saccharin - Cyclamate - Aspartame

50. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Nucleation or crystal formation and crystal growth.
Orange Juice
Cis
Olive Green