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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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1. What toxic pigment is found in cottonseed endosperm?
Milk
V=IR and P=VI or I x I x are
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Gossypol (it is removed during the oil refining process)

2. What is the main class of color compounds found in raspberries?
Degradation of protein and production of acid from sugar at the same time.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Anthocyanins
A concentrate of microfibrillar proteins of fish muscle.

3. What is the enzyme responsible for browning in apples and lettuce?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Polyphenol Oxidase
2.5

4. What is Carboxy-methyl cellulose often used for?
Thickener in foods
Onions ( or leeks)
Carrageenan
Pectins

5. What does MSG stand for?
Nucleation or crystal formation and crystal growth.
Monosodium Glutamate
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

6. 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?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
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.
.05 M HCL

7. What are the four basic flavors perceived by the tongue?
Aspartic Acid and Phenylalanine
Sweet - Salty - Sour - and Bitter
Daminozide
Fatty Acid and Alcohol

8. What is the structural difference between chlorophyll and pheophytia?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Pheophytia does not have magnesium in porphyrin ring.
Chlocophyllide does not have a phytoltail
Orange Juice

9. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Fat Oxidation
They act as catalysts - speeding the polymerization of acrylamide.
Whole Milk

10. Name three non-nutritive sweeteners approved for use in USA?
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.
Nucleation or crystal formation and crystal growth.
Fat Oxidation
Acsulfame-K - Saccharin - Cyclamate - Aspartame

11. What is the Peroxide Value a measure of?
NaCl (it dissociated to a 2M solution)
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Speed of Light
Fat Oxidation

12. What are proteins which are soluble in 50-80% ethanol known as?
The speed of a molecule is proportional to the surrounding voltage gradient.
Prolamines
ERH=100 x Aw
Polyphenol Oxidase

13. Are sorbitol and mannitol sweet?
Fructose
Yes
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
Primary butyric acid also caproic acid.

14. Waxes are composed of what two basic chemical entities?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Fatty Acid (Ester linked) to Fatty Alcohol
Gliadins and Glutenins
Lycopenes

15. Which two amino acids is the aspartame derived from?
Carmelization and Maillard
Olive Green
Pectin methylesterase & polygalacturonase
Aspartic Acid and Phenylalanine

16. What are the three main steps in the autooxidation of lipids?
pH below positive charge; pH at no charge; pH above negative charge
Initiation - Propagation - Termination
An enzyme that converts hydrogen peroxide to water plus oxygen.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

17. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Lamellar; Hexagonal I - II; Cubic
Covalent (strongest) and Hydrophobic (Weakest)
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

18. What are the three stages of oxidative rancidity?
.05
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Initiation - Propagation - and Termination
Pheophytin forms

19. What ketohexose is most significant to food chemists?
Fructose
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Oil in Water
.05 M HCL

20. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
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
20 carbons and 4 double bonds
NaCl (it dissociated to a 2M solution)
Lipase

21. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Arachidonic Acid
Olive Green
Glycosides of anthocyanidins
1 - 3 - 7-trimethylxanthine

22. How do sodium chloride and sucrose affect foam stability?
Orange Juice
Pectin Esterase - Polygalacturonase - Pectin Layase
Sodium chloride reduces foam stability and sucrose improves foam stability.
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. What enzyme is most responsible for browning bananas?
They act as catalysts - speeding the polymerization of acrylamide.
Oil in Water
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Polyphenol Oxidase

24. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
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.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

25. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
ERH=100 x Aw
Linoleic Acid
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

26. 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?
.05 M HCL
Arachidonic Acid
Prolamines
Glycosides of anthocyanidins

27. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
14
Osmosis
Lysine - Arginine - and Histidine
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

28. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Two aldehydes
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
.05 M HCL
Nucleation or crystal formation and crystal growth.

29. What is a polymorphism?
Monosodium Glutamate
Initiation - Propagation - Termination
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Negative log of the hydrogen concentration (mol/l).

30. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
It explodes
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

31. When heated ammonium bicarbonate decomposes to form what end products?
Primary butyric acid also caproic acid.
HPLC has higher pressure than FPLC
Prolamines
Ammonia - Water - Carbon Dioxide

32. What does HLB stand for and What does a high and low HLB value indicate?
Onions ( or leeks)
45% - 52% - 90%
They act as catalysts - speeding the polymerization of acrylamide.
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.

33. What ketohexose is most significant to food chemists?
Nucleation or crystal formation and crystal growth.
Gossypol (it is removed during the oil refining process)
The speed of a molecule is proportional to the surrounding voltage gradient.
Fructose

34. 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
Lysine - Arginine - and Histidine
RNA transcribed to DNA
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

35. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
V=IR and P=VI or I x I x are
Osmosis

36. What is the common name for 9 12 - cis-cis-octa dienoic acid?
No
Linoleic Acid
Thermus Aqauticus
Carrageenan

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).
Water
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Nucleation or crystal formation and crystal growth.

38. Name two reasons why fats are hydrogenated.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Olive Green
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
Pectin methyl esterase or galacturonase

39. Name three non-nutritive sweeteners approved for use in USA?
NaCl (it dissociated to a 2M solution)
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
The speed of a molecule is proportional to the surrounding voltage gradient.

40. How many carbon atoms are there in the fatty acid myristic acid?
14
Bright green
Pectin Esterase
Yellow

41. When heated ammonium bicarbonate decomposes to form what end products?
Whole Milk
pH 3-5
Ammonia - Water - Carbon Dioxide
Oil in Water

42. What is surimi?
It explodes
1 - 3 - 7-trimethylxanthine
A concentrate of microfibrillar proteins of fish muscle.
pH below positive charge; pH at no charge; pH above negative charge

43. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Aspartic Acid and Phenylalanine
Polyphenol Oxidase
pH below positive charge; pH at no charge; pH above negative charge
Onions ( or leeks)

44. What is the name given to a mixture of equal parts of Darel Lisomers?
V=IR and P=VI or I x I x are
Racemic Mixture
Acetoin
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

45. What enzyme causes hyrolytic rancidity in milk?
Sodium bicarbonate generates CO2
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Lipase
Carmelization and Maillard

46. What does the 'c' stand for in the equation E=mc2?
Chitin
Ammonia - Water - Carbon Dioxide
Speed of Light
Emulsoids

47. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Pheophytia does not have magnesium in porphyrin ring.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
14
Plasmids

48. In genetics What is conjugation?
HPLC has higher pressure than FPLC
It explodes
Racemic Mixture
DNA transferred by cell to cell contact (bacterial sex).

49. Name three factors useful in controlling enzyme activity.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Negative log of the hydrogen concentration (mol/l).
Racemic Mixture
Degradation of protein and production of acid from sugar at the same time.

50. At low water activity What is the main deteriorative concern?
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 methyl esterase or galacturonase
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.
Lipid oxidation