Test your basic knowledge |

Food 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 are the primary secondary - tertiary - and quaternary structures?
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.
2.5
RNA transcribed to DNA
Acsulfame-K - Saccharin - Cyclamate - Aspartame

2. Which two amino acids is the aspartame derived from?
Polyphenoloxidase
Cis
Aspartic Acid and Phenylalanine
HPLC has higher pressure than FPLC

3. What is the acid present in fish oil?
Lipid oxidation
Water
Arachidonic Acid
20 carbons and 4 double bonds

4. How do sodium chloride and sucrose affect foam stability?
2.5
Tryptophan
Sodium chloride reduces foam stability and sucrose improves foam stability.
Polyphenol Oxidase

5. 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
Yes
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Phenylketonuria
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

6. 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.
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.
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.
Prolamines

7. How many carbon atoms and how many double bonds are there in arachidonic acid?
Polyphenol Oxidase
Polyphenols
20 carbons and 4 double bonds
Troponins and Tropomyosin

8. What does the iodine value measure and how is it measured?
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
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Chlocophyllide does not have a phytoltail

9. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
1 - 3 - 7-trimethylxanthine
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Chitin

10. What does the acronym NPN stand for?
Phenylketonuria
1 - 3 - 7-trimethylxanthine
Non-protein nitrogen
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

11. What does Reichert-Meissert Number measure?
Primary butyric acid also caproic acid.
Ascorbic Acid and Citric Acid
20 carbons and 4 double bonds
It explodes

12. What does the saponification value measure and how is it measured?
Fructose
Anthocyanins
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Chitin

13. What toxic pigment is found in cottonseed endosperm?
Two aldehydes
1 - 3 - 7-trimethylxanthine
Gossypol (it is removed during the oil refining process)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

14. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
Glycosides of anthocyanidins
Whole Milk
Acsulfame-K - Saccharin - Cyclamate - Aspartame

15. What is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
Pectin methylesterase & polygalacturonase
Water
Yes

16. What is the main class of color compounds found in raspberries?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Pectins
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.
Anthocyanins

17. What enzyme is most responsible for browning bananas?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Polyphenol Oxidase
Carrageenan
Initiation - Propagation - and Termination

18. How does HPLC differ from FPLC?
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.
HPLC has higher pressure than FPLC
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Milk

19. Does kosmotrophil ion discourage water structure?
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.
Pectin Esterase - Polygalacturonase - Pectin Layase
No
Emulsoids

20. 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?
Anthocyanins
It explodes
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

21. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Sodium bicarbonate generates CO2
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Water
Bright green

22. What is the major color compound in tomatoes?
Capsaicin
Onions ( or leeks)
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

23. During freezing What are the two stages in the crystallization process?
ERH=100 x Aw
Acetoin
Chlocophyllide does not have a phytoltail
Nucleation or crystal formation and crystal growth.

24. In what food is butyric acid typically found?
V=IR and P=VI or I x I x are
NaCl (it dissociated to a 2M solution)
Milk
Water

25. What is Carboxy-methyl cellulose often used for?
Emulsoids
Thickener in foods
Osmosis
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

26. What is a polymorphism?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Whole Milk
Non-protein nitrogen
14

27. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Sweet - Salty - Sour - and Bitter
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Oil in Water

28. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Water
Anomeric
Erythorbic Acid
Yellow

29. Name two main gluten proteins.
Lipase
Oil in Water
Gliadins and Glutenins
Yes

30. Name three non-nutritive sweeteners approved for use in USA?
Degradation of protein and production of acid from sugar at the same time.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

31. What is surimi?
Lipid oxidation
A concentrate of microfibrillar proteins of fish muscle.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Phenophylin

32. What are the only phenols approved for use in the microbiological preservation of foods?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Parabens
Osmosis
Polyphenols

33. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
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.
They act as catalysts - speeding the polymerization of acrylamide.
Parabens
.05 M HCL

34. What are the three main steps in the autooxidation of lipids?
Racemic Mixture
Polyphenols
Fatty Acid (Ester linked) to Fatty Alcohol
Initiation - Propagation - Termination

35. 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?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Onions ( or leeks)
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.
Sodium chloride reduces foam stability and sucrose improves foam stability.

36. How does ERH relate to water activity?
Emulsoids
Initiation - Propagation - and Termination
ERH=100 x Aw
Yellow

37. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Linoleic Acid
Carrageenan
Onions ( or leeks)
Fat Oxidation

38. What is Ohm's Law and What is Power Equation?
An enzyme that converts hydrogen peroxide to water plus oxygen.
V=IR and P=VI or I x I x are
.05
Anthocyanins

39. What is the Peroxide Value a measure of?
Chlocophyllide does not have a phytoltail
Fat Oxidation
pH 3-5
Lycopenes

40. 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?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Chlocophyllide does not have a phytoltail
Troponins and Tropomyosin
Lamellar; Hexagonal I - II; Cubic

41. What happens to chlorophyll on heating?
Pheophytin forms
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Lysine - Arginine - and Histidine
Arachidonic Acid

42. What are the three main steps in the autooxidation of lipids?
D: None of the above
HPLC has higher pressure than FPLC
Initiation - Propagation - Termination
pH below positive charge; pH at no charge; pH above negative charge

43. Name two reasons why fats are hydrogenated.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
V=IR and P=VI or I x I x are
Degradation of protein and production of acid from sugar at the same time.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

44. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Capsaicin
Pectin Esterase - Polygalacturonase - Pectin Layase
The speed of a molecule is proportional to the surrounding voltage gradient.
The speed of a molecule is proportional to the surrounding voltage gradient.

45. Name two non-enzymatic browning reactions.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Erythorbic Acid
Carmelization and Maillard
Aspartic Acid and Phenylalanine

46. What charge will a protein have when the pH of its solution is below at - and above its pKa?
pH below positive charge; pH at no charge; pH above negative charge
Orange Juice
ERH=100 x Aw
Emulsoids

47. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
Monosodium Glutamate
Whole Milk
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

48. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
V=IR and P=VI or I x I x are
Acetoin
Glycosides of anthocyanidins
Osmosis

49. Name a commonly used household chemical leavening agent and the gas it generates.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Sodium bicarbonate generates CO2
Pheophytia does not have magnesium in porphyrin ring.
Polyphenols

50. When heated ammonium bicarbonate decomposes to form what end products?
Initiation - Propagation - and Termination
Ammonia - Water - Carbon Dioxide
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
ERH=100 x Aw