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Test your basic knowledge |
Food Chemistry
Start Test
Study First
Subjects
:
engineering
,
chemistry
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
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.
Bitter
Initiation - Propagation - Termination
Lamellar; Hexagonal I - II; Cubic
2. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
HPLC has higher pressure than FPLC
Ascorbic Acid and Citric Acid
Carmelization and Maillard
3. Name two main gluten proteins.
Polyphenol Oxidase
Gliadins and Glutenins
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Yes
4. What pigment was first designated as anthocyanins?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Primary butyric acid also caproic acid.
Anthocyanins
Blue pigment in flowers
5. Name the strongest biochemical bond and the weakest biochemical bond.
20 carbons and 4 double bonds
45% - 52% - 90%
Covalent (strongest) and Hydrophobic (Weakest)
Lysine - Arginine - and Histidine
6. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
45% - 52% - 90%
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Lamellar; Hexagonal I - II; Cubic
Onions ( or leeks)
7. 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?
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
.05 M HCL
Arachidonic Acid
Olive Green
8. What are 3 mesomorphic structures associated with lipids in the liquid state?
Lamellar; Hexagonal I - II; Cubic
Thermus Aqauticus
Nucleation or crystal formation and crystal growth.
Yellow
9. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Gliadins and Glutenins
Cis
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Bright green
10. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
RNA transcribed to DNA
NaCl (it dissociated to a 2M solution)
An enzyme that converts hydrogen peroxide to water plus oxygen.
Polyphenol Oxidase
11. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
Gossypol (it is removed during the oil refining process)
Olive Green
2.5
12. What is the common name for 9 12 - cis-cis-octa dienoic acid?
14
Linoleic Acid
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
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
13. How do sodium chloride and sucrose affect foam stability?
Anomeric
Non-protein nitrogen
Olive Green
Sodium chloride reduces foam stability and sucrose improves foam stability.
14. What are the only phenols approved for use in the microbiological preservation of foods?
Pectin methyl esterase or galacturonase
Daminozide
Water
Parabens
15. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
No
Thermus Aqauticus
Racemic Mixture
16. What are proteins which are soluble in 50-80% ethanol known as?
Lipase
Water
Prolamines
Bright green
17. Name three non-nutritive sweeteners approved for use in USA?
Sodium bicarbonate generates CO2
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Polyphenol Oxidase
Acsulfame-K - Saccharin - Cyclamate - Aspartame
18. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
A concentrate of microfibrillar proteins of fish muscle.
Capsaicin
Acetoin
pH 3-5
19. What compounds oxidize to form brown color in fruits and vegetables?
Pectins
Polyphenols
DNA transferred by cell to cell contact (bacterial sex).
V=IR and P=VI or I x I x are
20. 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.
Monosodium Glutamate
Phenophylin
Anthocyanins
21. What are the three stages of oxidative rancidity?
V=IR and P=VI or I x I x are
2.5
Initiation - Propagation - and Termination
Ascorbic Acid and Citric Acid
22. Alar is the trade name for what chemical compound?
Daminozide
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Sodium bicarbonate generates CO2
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
23. What ketohexose is most significant to food chemists?
Pectin Esterase
2.5
Fructose
Milk
24. Name 3 physical agents capable of denaturing proteins.
Polyphenols
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Prolamines
Thermus Aqauticus
25. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Oil in Water
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Chitin
20 carbons and 4 double bonds
26. What are the only phenols approved for use in the microbiological preservation of foods?
Pectin Esterase - Polygalacturonase - Pectin Layase
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Initiation - Propagation - and Termination
Parabens
27. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Speed of Light
14
An enzyme that converts hydrogen peroxide to water plus oxygen.
Yellow
28. How does HPLC differ from FPLC?
Non-protein nitrogen
HPLC has higher pressure than FPLC
.05
Acetoin
29. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Bright green
A concentrate of microfibrillar proteins of fish muscle.
Osmosis
Plasmids
30. What is the acid present in fish oil?
Pectin methylesterase & polygalacturonase
Lipid oxidation
Arachidonic Acid
.05 M HCL
31. 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
Thamautin
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
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
Browning of freshly cut surfaces of fruits and vegetables.
32. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
Plasmids
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
DNA transferred by cell to cell contact (bacterial sex).
33. What are two common reducing agents that break disulfide bonds in proteins?
Covalent (strongest) and Hydrophobic (Weakest)
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Capsaicin
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
34. Name 4 advantages of using enzymes in food processing.
Osmosis
Acetoin
Lycopenes
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
35. What is acid proteolysis?
2.5
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Tryptophan
Degradation of protein and production of acid from sugar at the same time.
36. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
It explodes
Pectin Esterase
Cis
Capsaicin
37. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Prolamines
Blue pigment in flowers
V=IR and P=VI or I x I x are
38. What is the Peroxide Value a measure of?
2.5
Chitin
RNA transcribed to DNA
Fat Oxidation
39. What metabolic end product does the Voges-Proskauer test detect?
Acetoin
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Lysine - Arginine - and Histidine
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
40. What does Acid Degree Value measure and how is it measured?
14
Phenophylin
Whole Milk
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
41. Alar is the trade name for what chemical compound?
Whole Milk
Pectin methyl esterase or galacturonase
Daminozide
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
42. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
Monosodium Glutamate
Fatty Acid and Alcohol
Pectins
43. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
14
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Capsaicin
44. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Lipid oxidation
Phenylketonuria
Plasmids
2.5
45. What pigment was first designated as anthocyanins?
.05 M HCL
Pectins
Blue pigment in flowers
Thermus Aqauticus
46. During freezing What are the two stages in the crystallization process?
Whole 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.
Nucleation or crystal formation and crystal growth.
Fatty Acid and Alcohol
47. 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.
Fatty Acid (Ester linked) to Fatty Alcohol
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
NaCl (it dissociated to a 2M solution)
48. In the enzyme Taq Polymerase What does Taq stand for?
HPLC has higher pressure than FPLC
Aspartic Acid and Phenylalanine
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Thermus Aqauticus
49. What is catalase?
Troponins and Tropomyosin
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
An enzyme that converts hydrogen peroxide to water plus oxygen.
They act as catalysts - speeding the polymerization of acrylamide.
50. Name two reasons why fats are hydrogenated.
Nucleation or crystal formation and crystal growth.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Tryptophan
Speed of Light