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Food Chemistry

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Answer 50 questions in 15 minutes.
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1. Name 5 chelating agents used in the food industry.
Bitter
Oil in Water
Erythorbic Acid
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

2. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Arachidonic Acid
Carrageenan
Lycopenes
HPLC has higher pressure than FPLC

3. When heated ammonium bicarbonate decomposes to form what end products?
Initiation - Propagation - Termination
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.
Ammonia - Water - Carbon Dioxide
Milk

4. How does ERH relate to water activity?
ERH=100 x Aw
Carrageenan
Browning of freshly cut surfaces of fruits and vegetables.
DNA transferred by cell to cell contact (bacterial sex).

5. Name three effects of protein denaturation.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Chlocophyllide does not have a phytoltail
Parabens
Chitin

6. How can a molecular weight of protein - DNA - and RNA be determined?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Parabens
Acetoin
.05

7. Alar is the trade name for what chemical compound?
pH below positive charge; pH at no charge; pH above negative charge
Daminozide
Troponins and Tropomyosin
Fructose

8. Name 3 physical agents capable of denaturing proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Milk
Non-protein nitrogen
Negative log of the hydrogen concentration (mol/l).

9. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
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
Pectin Esterase
Orange Juice

10. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
Pectin methylesterase & polygalacturonase
20 carbons and 4 double bonds
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

11. What toxic pigment is found in cottonseed endosperm?
Cis
Gossypol (it is removed during the oil refining process)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Phenylketonuria

12. Waxes are composed of what two basic chemical entities?
Gliadins and Glutenins
The speed of a molecule is proportional to the surrounding voltage gradient.
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.
Fatty Acid (Ester linked) to Fatty Alcohol

13. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Gliadins and Glutenins
NaCl (it dissociated to a 2M solution)
Olive Green
Two aldehydes

14. What is the Peroxide Value a measure of?
Aspartic Acid and Phenylalanine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Fat Oxidation
Degradation of protein and production of acid from sugar at the same time.

15. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Acsulfame-K - Saccharin - Cyclamate - Aspartame
ERH=100 x Aw
Linoleic Acid

16. When heated ammonium bicarbonate decomposes to form what end products?
Aspartic Acid and Phenylalanine
Ammonia - Water - Carbon Dioxide
Emulsoids
Racemic Mixture

17. What are two common reducing agents that break disulfide bonds in proteins?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
pH below positive charge; pH at no charge; pH above negative charge
Initiation - Propagation - Termination

18. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Prolamines
Primary butyric acid also caproic acid.
Capsaicin

19. What are the primary secondary - tertiary - and quaternary structures?
Daminozide
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
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.
Bitter

20. Name one way foam stability can be assessed.
Sucrose
Sodium chloride reduces foam stability and sucrose improves foam stability.
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.
Emulsoids

21. Name two main gluten proteins.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Gliadins and Glutenins
Water
Phenophylin

22. What are 3 mesomorphic structures associated with lipids in the liquid state?
Sweet - Salty - Sour - and Bitter
Lamellar; Hexagonal I - II; Cubic
pH below positive charge; pH at no charge; pH above negative charge
pH 3-5

23. Name one way foam stability can be assessed.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Lipase
Osmosis
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.

24. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Capsaicin
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.
Fat Oxidation
2.5

25. What are colloids that are stabilized by a layer of solvation called?
Ascorbic Acid and Citric Acid
Emulsoids
45% - 52% - 90%
Monosodium Glutamate

26. What effect would the addition of sodium bicarbonate have to chocolate?
Chitin
Polyphenoloxidase
Orange Juice
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. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Non-protein nitrogen
NaCl (it dissociated to a 2M solution)
Initiation - Propagation - Termination
Pheophytin forms

28. What pigment was first designated as anthocyanins?
Blue pigment in flowers
Chlocophyllide does not have a phytoltail
Emulsoids
Capsaicin

29. What does Acid Degree Value measure and how is it measured?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Polyphenols
Lipase
Onions ( or leeks)

30. 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?
Arachidonic Acid
Acetoin
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

31. What is the structural difference between chlorophyll and pheophytia?
Anomeric
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
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.
Pheophytia does not have magnesium in porphyrin ring.

32. Name three nonpolar polar - and charged amino acids.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Thickener in foods
.05 M HCL
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

33. What does the 'c' stand for in the equation E=mc2?
Olive Green
Polyphenol Oxidase
An enzyme that converts hydrogen peroxide to water plus oxygen.
Speed of Light

34. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Linoleic Acid
Ascorbic Acid and Citric Acid
Bitter

35. What is the protein efficiency ratio (PER) of casein?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Two aldehydes
2.5
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

36. What does the acronym NPN stand for?
It explodes
Non-protein nitrogen
V=IR and P=VI or I x I x are
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

37. What is an isomer that is cheaper than Vitamin C?
Covalent (strongest) and Hydrophobic (Weakest)
A concentrate of microfibrillar proteins of fish muscle.
Lysine - Arginine - and Histidine
Erythorbic Acid

38. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Daminozide
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

39. How many carbon atoms and how many double bonds are there in arachidonic acid?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
20 carbons and 4 double bonds
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Emulsoids

40. Alar is the trade name for what chemical compound?
Daminozide
The speed of a molecule is proportional to the surrounding voltage gradient.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

41. 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
Browning of freshly cut surfaces of fruits and vegetables.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Sodium bicarbonate generates CO2
45% - 52% - 90%

42. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
NaCl (it dissociated to a 2M solution)
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Phenylketonuria
Thermus Aqauticus

43. What does MSG stand for?
Bright green
Arachidonic Acid
Monosodium Glutamate
NaCl (it dissociated to a 2M solution)

44. How is pH defined?
Polyphenol Oxidase
Parabens
Negative log of the hydrogen concentration (mol/l).
Fructose

45. What is the name of the degradation compound of chlorophyll?
2.5
It explodes
Capsaicin
Phenophylin

46. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Parabens
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Polyphenoloxidase
20 carbons and 4 double bonds

47. What does the saponification value measure and how is it measured?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Polyphenol Oxidase

48. 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
Blue pigment in flowers
Plasmids
Water

49. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Pectin methylesterase & polygalacturonase
Degradation of protein and production of acid from sugar at the same time.
Covalent (strongest) and Hydrophobic (Weakest)
Two aldehydes

50. What enzyme is most responsible for browning bananas?
Sweet - Salty - Sour - and Bitter
Polyphenol Oxidase
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
Speed of Light