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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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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 two common compounds are used together as an antioxidative system?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pectin Esterase
Bitter
Ascorbic Acid and Citric Acid

2. In genetics What is conjugation?
Sucrose
DNA transferred by cell to cell contact (bacterial sex).
Gossypol (it is removed during the oil refining process)
Prolamines

3. What enzyme is most responsible for browning bananas?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Lycopenes
Non-protein nitrogen
Polyphenol Oxidase

4. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Primary butyric acid also caproic acid.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
They act as catalysts - speeding the polymerization of acrylamide.

5. Waxes are composed of what two basic chemical entities?
Polyphenol Oxidase
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Tryptophan
Fatty Acid (Ester linked) to Fatty Alcohol

6. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Water
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Sweet - Salty - Sour - and Bitter
Degradation of protein and production of acid from sugar at the same time.

7. What is the winterization process for an oil?
2.5
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Ascorbic Acid and Citric Acid
.05 M HCL

8. What two types of compounds are joined with an ester bond to make a wax?
Tryptophan
Fatty Acid and Alcohol
Daminozide
14

9. At what pH is benzoic acid most effective?
pH 3-5
A concentrate of microfibrillar proteins of fish muscle.
Bright green
Browning of freshly cut surfaces of fruits and vegetables.

10. Alar is the trade name for what chemical compound?
Daminozide
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.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Chlocophyllide does not have a phytoltail

11. What are the four basic flavors perceived by the tongue?
Cis
Sweet - Salty - Sour - and Bitter
Initiation - Propagation - Termination
Blue pigment in flowers

12. Contains the lowest content of water
Whole Milk
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Arachidonic 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

13. What is Ohm's Law and What is Power Equation?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Milk
V=IR and P=VI or I x I x are

14. How many carbon atoms and how many double bonds are there in arachidonic acid?
Yes
20 carbons and 4 double bonds
Arachidonic Acid
.05

15. What is acid proteolysis?
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.
Degradation of protein and production of acid from sugar at the same time.
Lycopenes

16. What is the chemical nomenclature for caffeine?
Polyphenols
1 - 3 - 7-trimethylxanthine
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

17. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Pheophytin forms
Linoleic Acid
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Speed of Light

18. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Capsaicin
Orange Juice
Yellow

19. How many polypeptide chains make up an antibody?
Pectin Esterase
Four
Thermus Aqauticus
2.5

20. How is pH defined?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Pectins
Negative log of the hydrogen concentration (mol/l).
Initiation - Propagation - and Termination

21. Name two main gluten proteins.
Gliadins and Glutenins
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.
Ammonia - Water - Carbon Dioxide
Fat Oxidation

22. What two enzymes degrade pectic substances?
Fructose
Thamautin
Pectin methylesterase & polygalacturonase
Initiation - Propagation - and Termination

23. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Two aldehydes
Initiation - Propagation - Termination
NaCl (it dissociated to a 2M solution)

24. What are the three main steps in the autooxidation of lipids?
Onions ( or leeks)
Sodium chloride reduces foam stability and sucrose improves foam stability.
ERH=100 x Aw
Initiation - Propagation - Termination

25. Are sorbitol and mannitol sweet?
14
Yes
1 - 3 - 7-trimethylxanthine
Pectin methylesterase & polygalacturonase

26. What does Reichert-Meissert Number measure?
Phenylketonuria
Primary butyric acid also caproic acid.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Fatty Acid (Ester linked) to Fatty Alcohol

27. Which two amino acids is the aspartame derived from?
Aspartic Acid and Phenylalanine
Erythorbic Acid
Pectin Esterase - Polygalacturonase - Pectin Layase
Carrageenan

28. What is the Peroxide Value a measure of?
Pheophytia does not have magnesium in porphyrin ring.
Racemic Mixture
Phenophylin
Fat Oxidation

29. Does kosmotrophil ion discourage water structure?
Linoleic Acid
Covalent (strongest) and Hydrophobic (Weakest)
No
Bright green

30. What does HLB stand for and What does a high and low HLB value indicate?
Ammonia - Water - Carbon Dioxide
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.
Lipid oxidation
Olive Green

31. Name three effects of protein denaturation.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Emulsoids
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Carmelization and Maillard

32. Name 5 proteins with good foaming properties.
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.
Lipid oxidation
Polyphenol Oxidase
Fatty Acid and Alcohol

33. What are the three stages of oxidative rancidity?
Carmelization and Maillard
Chlocophyllide does not have a phytoltail
Speed of Light
Initiation - Propagation - and Termination

34. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
RNA transcribed to DNA
Blue pigment in flowers
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Sodium bicarbonate generates CO2

35. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Polyphenoloxidase
Onions ( or leeks)
DNA transferred by cell to cell contact (bacterial sex).
Pheophytia does not have magnesium in porphyrin ring.

36. What is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
ERH=100 x Aw
Thickener in foods

37. Give one word for a carbon atom involved in hemiacetal or acetal formation.
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.
Anomeric
14
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

38. What is the name of the degradation compound of chlorophyll?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Phenophylin
Troponins and Tropomyosin
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

39. What is the name given to a mixture of equal parts of Darel Lisomers?
Racemic Mixture
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Water
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

40. What are the fructose contents in commercial HFCS products.
Fatty Acid (Ester linked) to Fatty Alcohol
Thermus Aqauticus
Aspartic Acid and Phenylalanine
45% - 52% - 90%

41. What are the only phenols approved for use in the microbiological preservation of foods?
Parabens
HPLC has higher pressure than FPLC
Fructose
Anthocyanins

42. Name three effects of protein denaturation.
Gliadins and Glutenins
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Onions ( or leeks)
Non-protein nitrogen

43. What does the acronym NPN stand for?
Non-protein nitrogen
Whole Milk
Olive Green
Emulsification

44. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Prolamines
Polyphenoloxidase

45. What is the major color compound in tomatoes?
Arachidonic Acid
Degradation of protein and production of acid from sugar at the same time.
Thickener in foods
Lycopenes

46. What metabolic end product does the Voges-Proskauer test detect?
Phenylketonuria
Acetoin
Pectins
Aspartic Acid and Phenylalanine

47. Name 3 factors influencing the consistency of commercial fats.
1 - 3 - 7-trimethylxanthine
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Acetoin
Polyphenoloxidase

48. What is the protein efficiency ratio (PER) of casein?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Sweet - Salty - Sour - and Bitter
Onions ( or leeks)
2.5

49. What does HLB stand for and What does a high and low HLB value indicate?
Acetoin
Pectin Esterase
Degradation of protein and production of acid from sugar at the same time.
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.

50. What are the fructose contents in commercial HFCS products.
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
45% - 52% - 90%
Fat Oxidation
Number of fatty acids present; mg KOH needed to saponify 1 g fat.