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 is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
Parabens
Fructose
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

2. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Polyphenol Oxidase
Two aldehydes
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Daminozide

3. What is Carboxy-methyl cellulose often used for?
Daminozide
Thickener in foods
Emulsoids
Bitter

4. Waxes are composed of what two basic chemical entities?
Fatty Acid (Ester linked) to Fatty Alcohol
Polyphenols
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Sucrose

5. What are the three main steps in the autooxidation of lipids?
Emulsoids
Initiation - Propagation - Termination
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Plasmids

6. Which two amino acids is the aspartame derived from?
Erythorbic Acid
Ammonia - Water - Carbon Dioxide
Chlocophyllide does not have a phytoltail
Aspartic Acid and Phenylalanine

7. What would be a safe processing time for heat processing green beans in a boiling water bath? A. 30 minutes B. 300 minutes C. Depends on the size of the food container D. None of the above
Acetoin
D: None of the above
Whole Milk
Gossypol (it is removed during the oil refining process)

8. 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.
Linoleic Acid
Lysine - Arginine - and Histidine
Nucleation or crystal formation and crystal growth.

9. What is the enzyme that softens tomatoes?
Pectin Esterase
Emulsification
Orange Juice
Cis

10. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Arachidonic Acid
Olive Green
Negative log of the hydrogen concentration (mol/l).

11. What does the 'c' stand for in the equation E=mc2?
Speed of Light
No
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

12. What is surimi?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Acetoin
A concentrate of microfibrillar proteins of fish muscle.
Fatty Acid and Alcohol

13. What does Acid Degree Value measure and how is it measured?
Nucleation or crystal formation and crystal growth.
45% - 52% - 90%
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Lipid oxidation

14. Name two enzymes that are involved in softening fruits.
Emulsoids
Pectin Esterase - Polygalacturonase - Pectin Layase
Erythorbic Acid
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.

15. What metabolic end product does the Voges-Proskauer test detect?
Two aldehydes
Acetoin
Daminozide
Milk

16. In the enzyme Taq Polymerase What does Taq stand for?
Thermus Aqauticus
Degradation of protein and production of acid from sugar at the same time.
Lycopenes
Carrageenan

17. What does the iodine value measure and how is it measured?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
.05
Bright green
It explodes

18. Which two amino acids is the aspartame derived from?
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.
V=IR and P=VI or I x I x are
Gossypol (it is removed during the oil refining process)
Aspartic Acid and Phenylalanine

19. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
V=IR and P=VI or I x I x are
Orange Juice
Fatty Acid and Alcohol

20. In genetics What is conjugation?
Water
DNA transferred by cell to cell contact (bacterial sex).
D: None of the above
Nucleation or crystal formation and crystal growth.

21. Alar is the trade name for what chemical compound?
Daminozide
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Blue pigment in flowers
ERH=100 x Aw

22. What are the three stages of oxidative rancidity?
Negative log of the hydrogen concentration (mol/l).
Initiation - Propagation - 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.
Initiation - Propagation - and Termination

23. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Glycosides of anthocyanidins
Water
Thermus Aqauticus
Polyphenol Oxidase

24. What does HLB stand for and What does a high and low HLB value indicate?
Degradation of protein and production of acid from sugar at the same time.
Negative log of the hydrogen concentration (mol/l).
Pectin Esterase - Polygalacturonase - Pectin Layase
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.

25. In what food is butyric acid typically found?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Anthocyanins
Milk

26. What is the enzyme responsible for browning in apples and lettuce?
Anomeric
Polyphenol Oxidase
Four
Water

27. 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
Polyphenol Oxidase
Browning of freshly cut surfaces of fruits and vegetables.
pH below positive charge; pH at no charge; pH above negative charge
Onions ( or leeks)

28. What happens to chlorophyll on heating?
Pheophytin forms
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
HPLC has higher pressure than FPLC
A concentrate of microfibrillar proteins of fish muscle.

29. What does the 'c' stand for in the equation E=mc2?
Speed of Light
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Phenophylin
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.

30. Name three effects of protein denaturation.
Water
Polyphenol Oxidase
Emulsoids
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

31. Name two main gluten proteins.
Browning of freshly cut surfaces of fruits and vegetables.
Gliadins and Glutenins
Daminozide
Linoleic Acid

32. 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).
Initiation - Propagation - and Termination
1 - 3 - 7-trimethylxanthine
Negative log of the hydrogen concentration (mol/l).

33. What metabolic end product does the Voges-Proskauer test detect?
Acetoin
Gossypol (it is removed during the oil refining process)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Aspartic Acid and Phenylalanine

34. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Tryptophan
Prolamines
They act as catalysts - speeding the polymerization of acrylamide.
Speed of Light

35. Name three non-nutritive sweeteners approved for use in USA?
The speed of a molecule is proportional to the surrounding voltage gradient.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Browning of freshly cut surfaces of fruits and vegetables.

36. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Onions ( or leeks)
pH below positive charge; pH at no charge; pH above negative charge
V=IR and P=VI or I x I x are
Bitter

37. Name 3 factors influencing the rate of lipid oxidation in foods.
Parabens
Carmelization and Maillard
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Acetoin

38. Name the most common functional property of phospholipids in food systems.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
No
Emulsification
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

39. What does Reichert-Meissert Number measure?
Primary butyric acid also caproic acid.
Phenylketonuria
2.5
No

40. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
RNA transcribed to DNA
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Fatty Acid (Ester linked) to Fatty Alcohol

41. How many polypeptide chains make up an antibody?
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.
Four
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Olive Green

42. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Bitter
Racemic Mixture
pH below positive charge; pH at no charge; pH above negative charge
Arachidonic Acid

43. What enzyme causes hyrolytic rancidity in milk?
Lipase
Ammonia - Water - Carbon Dioxide
45% - 52% - 90%
Phenylketonuria

44. In the enzyme Taq Polymerase What does Taq stand for?
Capsaicin
Milk
Thermus Aqauticus
Covalent (strongest) and Hydrophobic (Weakest)

45. What are the only phenols approved for use in the microbiological preservation of foods?
Parabens
RNA transcribed to DNA
Thermus Aqauticus
An enzyme that converts hydrogen peroxide to water plus oxygen.

46. Name 5 proteins with good foaming properties.
Lycopenes
Pheophytia does not have magnesium in porphyrin ring.
14
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.

47. What is the winterization process for an oil?
Initiation - Propagation - and Termination
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
RNA transcribed to DNA
Emulsification

48. Name 3 chemical agents capable of denaturing proteins.
Troponins and Tropomyosin
Phenophylin
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Two aldehydes

49. What is the protein efficiency ratio (PER) of casein?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Water
2.5
Gliadins and Glutenins

50. How is pH defined?
Fat Oxidation
Primary butyric acid also caproic acid.
Covalent (strongest) and Hydrophobic (Weakest)
Negative log of the hydrogen concentration (mol/l).