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Food Chemistry

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Answer 50 questions in 15 minutes.
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1. Name 5 chelating agents used in the food industry.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Plasmids
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

2. 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
Prolamines
Emulsoids
D: None of the above
Nucleation or crystal formation and crystal growth.

3. Name a naturally occurring protein sweetener.
Thamautin
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Nucleation or crystal formation and crystal growth.
Sodium bicarbonate generates CO2

4. What ketohexose is most significant to food chemists?
Linoleic Acid
An enzyme that converts hydrogen peroxide to water plus oxygen.
pH 3-5
Fructose

5. What two common compounds are used together as an antioxidative system?
Sucrose
Ascorbic Acid and Citric Acid
Lysine - Arginine - and Histidine
Polyphenol Oxidase

6. Which two amino acids is the aspartame derived from?
Polyphenol Oxidase
Aspartic Acid and Phenylalanine
Sodium bicarbonate generates CO2
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

7. Name three factors useful in controlling enzyme activity.
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.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

8. What are the only phenols approved for use in the microbiological preservation of foods?
Parabens
20 carbons and 4 double bonds
1 - 3 - 7-trimethylxanthine
Prolamines

9. What is catalase?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Sucrose
Lamellar; Hexagonal I - II; Cubic
Daminozide

10. In genetics What is conjugation?
DNA transferred by cell to cell contact (bacterial sex).
Milk
Tryptophan
Pheophytin forms

11. What two enzymes degrade pectic substances?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Pectin methylesterase & polygalacturonase
Erythorbic Acid
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

12. What is the structural difference between chlorophyll and chlocophyllide?
Chlocophyllide does not have a phytoltail
Thamautin
Sodium bicarbonate generates CO2
Lycopenes

13. What metabolic end product does the Voges-Proskauer test detect?
Acetoin
Yellow
Primary butyric acid also caproic acid.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

14. 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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
No
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Arachidonic Acid

15. What does Reichert-Meissert Number measure?
They act as catalysts - speeding the polymerization of acrylamide.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Primary butyric acid also caproic acid.
Degradation of protein and production of acid from sugar at the same time.

16. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Initiation - Propagation - Termination
Onions ( or leeks)
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Pectin methylesterase & polygalacturonase

17. What two common compounds are used together as an antioxidative system?
Ascorbic Acid and Citric Acid
Nucleation or crystal formation and crystal growth.
Oil in Water
Lipase

18. Name 3 chemical agents capable of denaturing proteins.
Anomeric
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Initiation - Propagation - Termination

19. Peptide bond formation results in the formation of what secondary compound?
Aspartic Acid and Phenylalanine
14
Water
NaCl (it dissociated to a 2M solution)

20. What are the three stages of oxidative rancidity?
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
Covalent (strongest) and Hydrophobic (Weakest)
.05
Initiation - Propagation - and Termination

21. Does kosmotrophil ion discourage water structure?
Aspartic Acid and Phenylalanine
No
Pheophytia does not have magnesium in porphyrin ring.
Lipase

22. What are the four basic flavors perceived by the tongue?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Gliadins and Glutenins
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Sweet - Salty - Sour - and Bitter

23. Name 5 proteins with good foaming properties.
pH 3-5
A concentrate of microfibrillar proteins of fish muscle.
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.
pH below positive charge; pH at no charge; pH above negative charge

24. What is the name of the degradation compound of chlorophyll?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Phenophylin
Degradation of protein and production of acid from sugar at the same time.
ERH=100 x Aw

25. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
It explodes
pH below positive charge; pH at no charge; pH above negative charge
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

26. What is the chemical nature of anthocyanins?
Yellow
Glycosides of anthocyanidins
Prolamines
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

27. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
It explodes
Osmosis
Racemic Mixture
Linoleic Acid

28. During freezing What are the two stages in the crystallization process?
Degradation of protein and production of acid from sugar at the same time.
Pheophytin forms
Nucleation or crystal formation and crystal growth.
Parabens

29. What are the only phenols approved for use in the microbiological preservation of foods?
Aspartic Acid and Phenylalanine
20 carbons and 4 double bonds
Parabens
Water

30. Give one word for a carbon atom involved in hemiacetal or acetal formation.
.05
Thermus Aqauticus
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Anomeric

31. At low water activity What is the main deteriorative concern?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
V=IR and P=VI or I x I x are
Lipid oxidation

32. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Ammonia - Water - Carbon Dioxide
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.
Bitter
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

33. What are the three main steps in the autooxidation of lipids?
Initiation - Propagation - Termination
Fatty Acid and Alcohol
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Two aldehydes

34. What does Acid Degree Value measure and how is it measured?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
A concentrate of microfibrillar proteins of fish muscle.
RNA transcribed to DNA
V=IR and P=VI or I x I x are

35. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Fatty Acid and Alcohol
Covalent (strongest) and Hydrophobic (Weakest)
Capsaicin

36. How can a molecular weight of protein - DNA - and RNA be determined?
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
Polyphenoloxidase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

37. Contains the lowest content of water
Linoleic Acid
Sodium chloride reduces foam stability and sucrose improves foam stability.
No
Whole Milk

38. Is a disaccharide
Chitin
Anthocyanins
Sucrose
Osmosis

39. 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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Browning of freshly cut surfaces of fruits and vegetables.
D: None of the above
Racemic Mixture

40. How is pH defined?
Blue pigment in flowers
20 carbons and 4 double bonds
Negative log of the hydrogen concentration (mol/l).
1 - 3 - 7-trimethylxanthine

41. What happens to chlorophyll on heating?
DNA transferred by cell to cell contact (bacterial sex).
Pheophytin forms
20 carbons and 4 double bonds
Cis

42. What is the enzyme that softens tomatoes?
Phenylketonuria
Olive Green
Lipid oxidation
Pectin Esterase

43. What is the name given to a mixture of equal parts of Darel Lisomers?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Racemic Mixture
Pheophytia does not have magnesium in porphyrin ring.
NaCl (it dissociated to a 2M solution)

44. What is a polymorphism?
Whole Milk
Fatty Acid (Ester linked) to Fatty Alcohol
Thickener in foods
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

45. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
Phenylketonuria
V=IR and P=VI or I x I x are
Thamautin

46. Define molarity molality - and normality.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
They act as catalysts - speeding the polymerization of acrylamide.
.05 M HCL
Water

47. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Parabens
Polyphenols
Polyphenols
Water

48. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Tryptophan
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
.05 M HCL

49. What does HLB stand for and What does a high and low HLB value indicate?
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
NaCl (it dissociated to a 2M solution)
Phenophylin

50. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
Milk
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Thamautin