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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 are colloids that are stabilized by a layer of solvation called?
Sodium chloride reduces foam stability and sucrose improves foam stability.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Emulsoids
NaCl (it dissociated to a 2M solution)

2. What is the common name for 9 12 - cis-cis-octa dienoic acid?
pH below positive charge; pH at no charge; pH above negative charge
Linoleic Acid
Plasmids
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.

3. What is the chemical nomenclature for caffeine?
Capsaicin
1 - 3 - 7-trimethylxanthine
Ascorbic Acid and Citric Acid
Fat Oxidation

4. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Tryptophan
Primary butyric acid also caproic acid.
Olive Green

5. At what pH is benzoic acid most effective?
Daminozide
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
pH 3-5
Two aldehydes

6. What ketohexose is most significant to food chemists?
ERH=100 x Aw
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Fructose
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

7. 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
Pectin methylesterase & polygalacturonase
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Polyphenoloxidase

8. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Erythorbic Acid
Bitter
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
.05 M HCL

9. Name the strongest biochemical bond and the weakest biochemical bond.
Blue pigment in flowers
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Covalent (strongest) and Hydrophobic (Weakest)

10. What is acid proteolysis?
Chlocophyllide does not have a phytoltail
Degradation of protein and production of acid from sugar at the same time.
Oil in Water
.05 M HCL

11. What does Acid Degree Value measure and how is it measured?
Lycopenes
DNA transferred by cell to cell contact (bacterial sex).
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Emulsoids

12. How does HPLC differ from FPLC?
Pectin methylesterase & polygalacturonase
Onions ( or leeks)
Cis
HPLC has higher pressure than FPLC

13. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
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.
ERH=100 x Aw
Phenophylin

14. What is a polymorphism?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Daminozide
Fructose
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

15. Which two amino acids is the aspartame derived from?
Four
Initiation - Propagation - and Termination
Prolamines
Aspartic Acid and Phenylalanine

16. At what pH is benzoic acid most effective?
Yes
pH 3-5
Lipid oxidation
Initiation - Propagation - and Termination

17. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
Polyphenol Oxidase
Sweet - Salty - Sour - and Bitter
Chlocophyllide does not have a phytoltail

18. During freezing What are the two stages in the crystallization process?
Nucleation or crystal formation and crystal growth.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Olive Green

19. When heated ammonium bicarbonate decomposes to form what end products?
14
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Ammonia - Water - Carbon Dioxide
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. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Aspartic Acid and Phenylalanine
Bitter
Anthocyanins
Pectin methyl esterase or galacturonase

21. What is the enzyme that softens tomatoes?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
It explodes
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Pectin Esterase

22. What is the name of the degradation compound of chlorophyll?
Phenophylin
Lipase
1 - 3 - 7-trimethylxanthine
They act as catalysts - speeding the polymerization of acrylamide.

23. What is the protein efficiency ratio (PER) of casein?
Anomeric
2.5
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Fructose

24. What does HLB stand for and What does a high and low HLB value indicate?
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.
Osmosis
Yes
Daminozide

25. Name 5 proteins with good foaming properties.
Gliadins and Glutenins
Negative log of the hydrogen concentration (mol/l).
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.
Pectin Esterase

26. Alar is the trade name for what chemical compound?
.05
Daminozide
Pectin Esterase
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

27. What is the chemical nature of anthocyanins?
Parabens
Sweet - Salty - Sour - and Bitter
Glycosides of anthocyanidins
Tryptophan

28. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
NaCl (it dissociated to a 2M solution)
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

29. Name 5 chelating agents used in the food industry.
Initiation - Propagation - and Termination
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Erythorbic Acid
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

30. What are the three stages of oxidative rancidity?
Orange Juice
Initiation - Propagation - and Termination
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.
Parabens

31. Name two non-enzymatic browning reactions.
Carmelization and Maillard
Chlocophyllide does not have a phytoltail
Bright green
Erythorbic Acid

32. What is catalase?
Pectins
An enzyme that converts hydrogen peroxide to water plus oxygen.
20 carbons and 4 double bonds
Chitin

33. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
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
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.
Oil in Water
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

34. Is a disaccharide
Speed of Light
Sucrose
Speed of Light
.05 M HCL

35. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Pectins
Sucrose
Thamautin
Anomeric

36. Name the most common functional property of phospholipids in food systems.
Emulsification
pH below positive charge; pH at no charge; pH above negative charge
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
DNA transferred by cell to cell contact (bacterial sex).

37. 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
Covalent (strongest) and Hydrophobic (Weakest)
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Olive Green

38. What ketohexose is most significant to food chemists?
2.5
Fructose
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 - Polygalacturonase - Pectin Layase

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?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Pectins
Troponins and Tropomyosin
It explodes

40. How do sodium chloride and sucrose affect foam stability?
HPLC has higher pressure than FPLC
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Arachidonic Acid
Sodium chloride reduces foam stability and sucrose improves foam stability.

41. What metabolic end product does the Voges-Proskauer test detect?
Onions ( or leeks)
Acetoin
Cis
pH below positive charge; pH at no charge; pH above negative charge

42. What compounds oxidize to form brown color in fruits and vegetables?
Sodium bicarbonate generates CO2
Racemic Mixture
V=IR and P=VI or I x I x are
Polyphenols

43. How can a molecular weight of protein - DNA - and RNA be determined?
Fat Oxidation
Anthocyanins
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
NaCl (it dissociated to a 2M solution)

44. What is the structural difference between chlorophyll and pheophytia?
Pheophytia does not have magnesium in porphyrin ring.
Browning of freshly cut surfaces of fruits and vegetables.
Capsaicin
Nucleation or crystal formation and crystal growth.

45. Name three factors useful in controlling enzyme activity.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
No
Pectins

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

47. What does the acronym NPN stand for?
Non-protein nitrogen
Monosodium Glutamate
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Fat Oxidation

48. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Pectin Esterase - Polygalacturonase - Pectin Layase
Polyphenol Oxidase

49. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Daminozide
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
1 - 3 - 7-trimethylxanthine
Orange Juice

50. How many carbon atoms are there in the fatty acid myristic acid?
Olive Green
Linoleic Acid
14
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces