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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. What is Carboxy-methyl cellulose often used for?
Pectin methyl esterase or galacturonase
Thickener in foods
Cis
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
2. What two common compounds are used together as an antioxidative system?
Thermus Aqauticus
20 carbons and 4 double bonds
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Ascorbic Acid and Citric Acid
3. When heated ammonium bicarbonate decomposes to form what end products?
Ammonia - Water - Carbon Dioxide
Daminozide
Daminozide
The speed of a molecule is proportional to the surrounding voltage gradient.
4. What is the structural difference between chlorophyll and chlocophyllide?
They act as catalysts - speeding the polymerization of acrylamide.
Whole Milk
Chlocophyllide does not have a phytoltail
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
5. What is acid proteolysis?
Yellow
Degradation of protein and production of acid from sugar at the same time.
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.
Pectin Esterase - Polygalacturonase - Pectin Layase
6. What is the chemical nature of anthocyanins?
Polyphenol Oxidase
pH below positive charge; pH at no charge; pH above negative charge
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Glycosides of anthocyanidins
7. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Chitin
Osmosis
Pectin Esterase - Polygalacturonase - Pectin Layase
8. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
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.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Daminozide
9. What is the structural difference between chlorophyll and chlocophyllide?
Primary butyric acid also caproic acid.
.05 M HCL
Chlocophyllide does not have a phytoltail
Blue pigment in flowers
10. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Bitter
Lycopenes
Oil in Water
pH below positive charge; pH at no charge; pH above negative charge
11. Name two reasons why fats are hydrogenated.
Thamautin
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
12. 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.
Fatty Acid and Alcohol
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.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
13. What are colloids that are stabilized by a layer of solvation called?
Emulsoids
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
No
Pheophytin forms
14. Waxes are composed of what two basic chemical entities?
Bitter
Fatty Acid (Ester linked) to Fatty Alcohol
Lysine - Arginine - and Histidine
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
15. What are the fructose contents in commercial HFCS products.
.05 M HCL
45% - 52% - 90%
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.
Sodium chloride reduces foam stability and sucrose improves foam stability.
16. Name the two components that comprise the relaxing factor in muscle fibers.
Gossypol (it is removed during the oil refining process)
Pectin Esterase
Troponins and Tropomyosin
Lipid oxidation
17. 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.
Chlocophyllide does not have a phytoltail
Fat Oxidation
Plasmids
18. Contains the lowest content of water
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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.
Lamellar; Hexagonal I - II; Cubic
Whole Milk
19. Peptide bond formation results in the formation of what secondary compound?
It explodes
14
Pectins
Water
20. How many polypeptide chains make up an antibody?
Capsaicin
HPLC has higher pressure than FPLC
Four
Onions ( or leeks)
21. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Gliadins and Glutenins
Tryptophan
Fatty Acid and Alcohol
14
22. How can a molecular weight of protein - DNA - and RNA be determined?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Pheophytin forms
Pectin Esterase
23. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
Aspartic Acid and Phenylalanine
Bright green
Four
24. What does Reichert-Meissert Number measure?
Fat Oxidation
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Primary butyric acid also caproic acid.
Tryptophan
25. Name 5 chelating agents used in the food industry.
Lipase
ERH=100 x Aw
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Monosodium Glutamate
26. What does MSG stand for?
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
The speed of a molecule is proportional to the surrounding voltage gradient.
Monosodium Glutamate
Orange Juice
27. Name 3 physical agents capable of denaturing proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Chlocophyllide does not have a phytoltail
Bitter
Whole Milk
28. What happens to chlorophyll on heating?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Osmosis
Pheophytin forms
RNA transcribed to DNA
29. Will lipid oxidation be higher at a water activity of .05 or .5?
.05
Bitter
Troponins and Tropomyosin
Aspartic Acid and Phenylalanine
30. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Carrageenan
Olive Green
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Emulsification
31. What compounds oxidize to form brown color in fruits and vegetables?
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.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
HPLC has higher pressure than FPLC
Polyphenols
32. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
Sodium bicarbonate generates CO2
Aspartic Acid and Phenylalanine
Fat Oxidation
33. In the enzyme Taq Polymerase What does Taq stand for?
1 - 3 - 7-trimethylxanthine
Thermus Aqauticus
Primary butyric acid also caproic acid.
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.
Yes
Bitter
Primary butyric acid also caproic 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
35. What happens to chlorophyll on heating?
Pheophytin forms
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
Lamellar; Hexagonal I - II; Cubic
Lipid oxidation
36. 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
Daminozide
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Nucleation or crystal formation and crystal growth.
Browning of freshly cut surfaces of fruits and vegetables.
37. What effect would the addition of sodium bicarbonate have to chocolate?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
RNA transcribed to DNA
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
38. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Initiation - Propagation - Termination
Sucrose
Orange Juice
Covalent (strongest) and Hydrophobic (Weakest)
39. Name a commonly used household chemical leavening agent and the gas it generates.
Fatty Acid and Alcohol
Phenophylin
Sodium bicarbonate generates CO2
Primary butyric acid also caproic acid.
40. What toxic pigment is found in cottonseed endosperm?
Olive Green
.05
Gossypol (it is removed during the oil refining process)
Pectins
41. 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 explodes
HPLC has higher pressure than FPLC
Milk
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
42. When heated ammonium bicarbonate decomposes to form what end products?
Pheophytin forms
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Ammonia - Water - Carbon Dioxide
Phenophylin
43. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Pectin Esterase
pH below positive charge; pH at no charge; pH above negative charge
Anthocyanins
Parabens
44. Alar is the trade name for what chemical compound?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Four
Thamautin
Daminozide
45. What is the acid present in fish oil?
Water
Arachidonic Acid
Prolamines
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
46. What ketohexose is most significant to food chemists?
Chitin
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Onions ( or leeks)
Fructose
47. What two types of compounds are joined with an ester bond to make a wax?
It explodes
A concentrate of microfibrillar proteins of fish muscle.
Yes
Fatty Acid and Alcohol
48. Name 3 reasons it is advantageous to obtain enzymes from microorganisms.
49. What is an isomer that is cheaper than Vitamin C?
Emulsification
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Degradation of protein and production of acid from sugar at the same time.
Erythorbic Acid
50. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
Milk
Cis
RNA transcribed to DNA
Thermus Aqauticus