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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 chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Covalent (strongest) and Hydrophobic (Weakest)
Blue pigment in flowers
Glycosides of anthocyanidins
Capsaicin

2. Name two enzymes that are involved in softening fruits.
Phenophylin
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Pectin Esterase - Polygalacturonase - Pectin Layase
RNA transcribed to DNA

3. Name 4 advantages of using enzymes in food processing.
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
14
Initiation - Propagation - Termination
.05

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

5. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
Chitin
Two aldehydes
Pectin Esterase

6. Name 3 factors influencing the rate of lipid oxidation in foods.
Pectin Esterase - Polygalacturonase - Pectin Layase
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Acetoin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

7. How is pH defined?
Negative log of the hydrogen concentration (mol/l).
Thickener in foods
.05 M HCL
45% - 52% - 90%

8. What is the protein efficiency ratio (PER) of casein?
2.5
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

9. Name 5 proteins with good foaming properties.
Thermus Aqauticus
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.
Pheophytia does not have magnesium in porphyrin ring.
Plasmids

10. What is Carboxy-methyl cellulose often used for?
Fatty Acid and Alcohol
Thickener in foods
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

11. Name 4 advantages of using enzymes in food processing.
Racemic Mixture
V=IR and P=VI or I x I x are
Carrageenan
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

12. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
Speed of Light
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

13. Does kosmotrophil ion discourage water structure?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
No
Blue pigment in flowers
Racemic Mixture

14. What are the fructose contents in commercial HFCS products.
Pectin methyl esterase or galacturonase
Sucrose
45% - 52% - 90%
Pheophytin forms

15. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Polyphenoloxidase
Nucleation or crystal formation and crystal growth.
Non-protein nitrogen

16. What is the major color compound in tomatoes?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
14
Degradation of protein and production of acid from sugar at the same time.
Lycopenes

17. Name two enzymes that are involved in softening fruits.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Pectin Esterase - Polygalacturonase - Pectin Layase
Water

18. What are soluble polymers of anhydro-galacturonic acid and its esters called?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Pectins
Fructose
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

19. How can a molecular weight of protein - DNA - and RNA be determined?
Blue pigment in flowers
.05 M HCL
Cis
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

20. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
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.
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
Water
Oil in Water

21. What is the Peroxide Value a measure of?
Pheophytin forms
Fat Oxidation
Troponins and Tropomyosin
Lysine - Arginine - and Histidine

22. How do sodium chloride and sucrose affect foam stability?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Sodium chloride reduces foam stability and sucrose improves foam stability.
2.5
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

23. Is a disaccharide
Ammonia - Water - Carbon Dioxide
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Sucrose
Covalent (strongest) and Hydrophobic (Weakest)

24. What is the chemical nature of anthocyanins?
Lysine - Arginine - and Histidine
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.
Glycosides of anthocyanidins

25. What is surimi?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
A concentrate of microfibrillar proteins of fish muscle.
Pectin methylesterase & polygalacturonase
Covalent (strongest) and Hydrophobic (Weakest)

26. What effect would the addition of sodium bicarbonate have to chocolate?
Thamautin
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
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.
Pheophytin forms

27. What is Ohm's Law and What is Power Equation?
V=IR and P=VI or I x I x are
Fat Oxidation
Initiation - Propagation - Termination
1 - 3 - 7-trimethylxanthine

28. 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.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
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.
Arachidonic Acid

29. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Lipase
Lamellar; Hexagonal I - II; Cubic
Daminozide
They act as catalysts - speeding the polymerization of acrylamide.

30. What enzyme causes hyrolytic rancidity in milk?
Four
ERH=100 x Aw
Chlocophyllide does not have a phytoltail
Lipase

31. Name three factors useful in controlling enzyme activity.
Yellow
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
45% - 52% - 90%
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

32. What is the acid present in fish oil?
Cis
Arachidonic Acid
Monosodium Glutamate
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.

33. What are the limiting amino acids in corn - potato - and green peas?
Four
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Browning of freshly cut surfaces of fruits and vegetables.

34. What is an isomer that is cheaper than Vitamin C?
Glycosides of anthocyanidins
Onions ( or leeks)
Erythorbic Acid
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

35. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
It explodes
Racemic Mixture
Lycopenes

36. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Onions ( or leeks)
Speed of Light
Lipid oxidation
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

37. How do sodium chloride and sucrose affect foam stability?
Non-protein nitrogen
Negative log of the hydrogen concentration (mol/l).
Sodium chloride reduces foam stability and sucrose improves foam stability.
Browning of freshly cut surfaces of fruits and vegetables.

38. What two common compounds are used together as an antioxidative system?
Ascorbic Acid and Citric Acid
Negative log of the hydrogen concentration (mol/l).
Sucrose
Gliadins and Glutenins

39. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
14
Gossypol (it is removed during the oil refining process)
1 - 3 - 7-trimethylxanthine
It explodes

40. What is the Peroxide Value a measure of?
Fat Oxidation
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.
Tryptophan
Racemic Mixture

41. What are the four basic flavors perceived by the tongue?
Gossypol (it is removed during the oil refining process)
20 carbons and 4 double bonds
Sweet - Salty - Sour - and Bitter
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.

42. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Fatty Acid and Alcohol
Primary butyric acid also caproic acid.
.05 M HCL
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

43. What compounds oxidize to form brown color in fruits and vegetables?
2.5
Fatty Acid (Ester linked) to Fatty Alcohol
Ascorbic Acid and Citric Acid
Polyphenols

44. Name 3 chemical agents capable of denaturing proteins.
Primary butyric acid also caproic acid.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
V=IR and P=VI or I x I x are
Fructose

45. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Pectin methylesterase & polygalacturonase
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Emulsification
Polyphenol Oxidase

46. Name the most common functional property of phospholipids in food systems.
Polyphenols
Emulsification
Nucleation or crystal formation and crystal growth.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

47. What is the name given to a mixture of equal parts of Darel Lisomers?
RNA transcribed to DNA
Monosodium Glutamate
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
Racemic Mixture

48. Name 3 physical agents capable of denaturing proteins.
.05 M HCL
Linoleic Acid
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Phenophylin

49. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Browning of freshly cut surfaces of fruits and vegetables.
Carrageenan
Chitin
Sodium chloride reduces foam stability and sucrose improves foam stability.

50. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Covalent (strongest) and Hydrophobic (Weakest)
Daminozide
Polyphenol Oxidase