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Flashcards in Food Chemistry Deck (259):
1

Would a more hydrophilic substance have a higher or lower HLB than a hydrophobic substance?

Higher

2

Within what range of its pK is a buffering agent is effective?

Plus or minus 1 pH unit

3

Why do triglycerides normally soften slowly and don't have sharp melting points?

Triglycerides can contain up to three different fatty acids and each fatty acid will have a different melting point.

4

Why do seed proteins like soy protein have a high isoelectric point?

Most of the glutamic and aspartic acid residues are amidated

5

Which sugar alcohol has the same sweetness as sucrose?

Xylitol

6

Which of the following solution would exhibit the lowest aw? Which the highest? a) 1 M NaCl b) 1 M glycerol c) 1 M glucose d) 1 M sucrose e) 1 M CaCl2

Lowest – 1 M sucrose, Highest – 1 M CaCl2

7

Which of the following gums should not be included in a formulation of a product, which does not require heating? Locust bean gum, Guar gum, Xanthan gum, or Gum Arabic

locust bean gum

8

Which of the following are emulsifying salts for use in processing cheese? sodium tartrate, sodium chloride, potassium chloride, all of the above

sodium tartrate (a)

9

Which is more viscous: high DE or low DE corn syrup?

Low DE

10

Which has a higher melting point: oleic or palmitic?

Palmitic

11

Which fatty acid would be expected to have the highest iodine value- linoleic, oleic, or linolenic?

Linolenic (18:3 - has more unsaturation) (oleic has 1 double bond, linoleic has 2 double bonds)

12

Which amino acids may form dehydroalanine?

Cysteine, cystine, serine, P-serine

13

Where is banana oil obtained from?

Trick question? No oil in bananas?

14

Where does isoamylase and pullinase attack on a starch molecule?

Breaks the alpha-1,6 bond between 2 glucose molecules

15

When hydrogen peroxide is added, a positive catalase test shows the formation of what?

Oxygen

16

When alpha-amylase attacks starch, what products are formed?

Alpha-amylase hydrolyzes alpha 1,4 glycosidic bonds producing glucose, maltose, and dextrins

17

What vitamin is a 6-carbon compound with a structure very similar to glucose?

Vitamin C (ascorbic acid)

18

What type of secondary protein structure is most prevalent in β-lactoglobulin?

β-sheet

19

What type of pectin will form gels if the pH is below 3.6?

High methoxyl pectin

20

What type of pectin interacts with divalent cations to form gels?

Low methoxyl pectin

21

What type of gum as three main fractions based upon increasing sulfate ester content, known as kappa, iota, and lambda?

Carrageenans

22

What two sugars comprise lactose?

Glucose and galactose

23

What term is given to strongly hydrophillic macromolecular materials that dissolve or disperse in water producing a thickening or viscosifying effect?

Hydrocolloids

24

What term describes the spontaneous loss of fluid from a food gel?

Syneresis

25

What term describes the ability of a fat to exist in multiple crystal forms?

Polymorphorism

26

What results from the hydrolysis of a specific Phe105-Met106 bond in kappa casein?

Destabilization of the casein micelles (cheese curd formation)

27

What protein is responsible for transferring iron from the intestine to the blood stream?

Transferrin

28

What non-nutritive protein is a major component of connective tissue?

Collagen

29

What molecule is a polymer of α-D-galacturonic acid that is produced commercially by extraction of citrus fruits and apples and is used to make jelly?

Pectin

30

What method, often used in protein analysis, aids a researcher in determining the relative percentages of alpha-helix and beta-sheets in a single protein?

Circular Dichroism (CD)

31

What is winterizing?

Refining step in which oils are chilled carefully to precipitate and remove fractions with high melting points that would interfere with the pourability of salad dressings or other products containing the oils.

32

What is the water activity range for intermediate foods?

0.6 - 0.85

33

What is the trivial name for the saturated fatty acid with 24 carbons?

Lignociric acid

34

What is the third most abundant element in the Earth’s crust, used to make packaging materials? a) oxygen b) silica c) aluminum

c) aluminum

35

What is the term used to describe uncontrolled fat crystallization which gives chocolate an impaired texture and a gray surface appearance?

Fat Bloom

36

What is the term given to the disruption of a protein’s secondary, tertiary and quarternary structure without loss of the proteins primary structure?

Protein denaturation

37

What is the term for the methyl end of a fatty acid?

Omega

38

What is the term for the carboxyl end of a fatty acid?

Alpha position

39

What is the sweetest monosaccharide?

Fructose

40

What is the structural 5 carbon unit of carotenoids?

Isoprene or isoprenoid unit

41

What is the source of gum arabic?

Acacia tree

42

What is the source of alginates?

Brown seaweed extracts (Phaeophyceae)

43

What is the source of agar and carageenan?

Irish moss (Chondrus crispus) and other red algae/seaweed

44

What is the solid fat index?

Percent of solution that is crystalline at a specific temp

45

What is the significance of dehydroalanine in food?

Dehydroalanine may produce protein cross-links from its reaction with other amino acids decreasing that protein’s nutritive value.

46

What is the role of a surfactant in bakery products?

Modifies the texture of the food by interacting with the proteins and polysaccharides and helps stabilize the dough

47

What is the product of sugar reduction: a. acid, b. polyol, c. deoxysugar?

b. polyol

48

What is the primary ingredient in sand?

Silica (Silicon dioxide)

49

What is the natural carotenoid substance in tomatoes that acts as an antioxidant?

Lycopene

50

What is the name of the gummy and slimy polymer that sometimes clogs the lines and pipes of sugar refineries and what organism produces this polymer?

Dextran - produced by Leuconostoc mesenteroides

51

What is the name for higher alcohols esterified with fatty acids?

Waxes

52

What is the name for a 6-carbon carbohydrate that exist is a five membered ring?

Furanose

53

What is the most widely distributed sugar in nature?

D-glucose

54

What is the most stable polymorphic form of triglycerides?

Beta (highest melting point)

55

What is the molarity of 0.5 moles of NaCl in 500 mL of water?

1.0 M

56

What is the microbial gum most commonly used in salad dressings?

Xanthan gum

57

What is the major linkage in starch?

Alpha 1-4

58

What is the major carotenoid pigment in corn?

Xanthophyll

59

What is the major apocarotenoid in annatto?

Bixin

60

What is the isoelectric point of caseins?

4.6

61

What is the form of pectic substances found in unripe fruit and some vegetables?

Protopectin - a methylated, very long polymer of galacturonic acid

62

What is the difference between high-methoxy pectin and low-methoxy pectin?

HMP>50% of carboxyl groups are in the methyl ester form; LMP has

63

What is the difference between a fat and an oil?

Fat is usually solid at room temperature whereas oil is liquid at room temperature, i.e., fats have higher melting points than oils.

64

What is the complex polymer, comprised of phenylpropane units, associated with cell walls of plants?

Lignin

65

What is the common name for 9,12,15-octadecatrienoic acid?

Linolenic acid

66

What is the common catalyst used for hydrogenation of unsaturated oils?

Nickel – other catalysts include: copper, platinum and boron

67

What is the basic building block for terpenoid biosynthesis called?

Isoprene or isoprene unit

68

What is racemization?

Exposure of amino acids to high pH causing a change from the L to the D configuration

69

What is Poising Capacity?

Apparent resistance to change in redox potential.

70

What is petroleum ether?

Mixture of short chain hydrocarbons; primarily pentane and hexane

71

What is pectic acid and where is it usually found?

Pectic acid is the smallest of the pectic substances and lacks methyl esters; found in overly ripe, very soft fruits and vegetables; no longer has gel-forming ability.

72

What is invert sugar?

Hydrolysis of sucrose to glucose and fructose

73

What is interesterification?

A process which involves an exchange of an acyl group among triglycerides

74

What is hysteresis?

Dehydrated food lose water holding capacity and they never rehydrate to their initial moisture levels

75

What is hydrolyzed during the enzymatic coagulation of milk?

Kappa-casein

76

What is common chemical intermediate in fat, protein, and carbohydrate metabolism?

Acetyl CoA

77

What is another name for the oliosaccharide that is called galactose 1-6 galactose or 1-2 fructose?

Stachyose

78

What is another name for phosphatidylcholine?

Lecithin

79

What is another name for Carob gum?

Locust bean gum, (also St. John’s Bread)

80

What is also formed when a dipeptide bond is made?

Water

81

What ingredient is used to inhibit haze formation during beer making?

Tannin

82

What happens to the melting point of a lipid/oil when its overall level of saturation is increased?

Melting point increases

83

What gelling agent is produced from the microorganism Alcaligenes faecalis var. myxogenes (a gram negative psychrotroph associated with refrigerated spoilage)?

Curdlan (Pureglucan)

84

What factors influence O-R Potential?

Composition of food, oxygen tension in atmosphere, and access that the atmosphere has to food

85

What enzyme is used as an indicator of proper blanching of vegetables?

Peroxidase

86

What enzyme is responsible for the cleavage of lactose from a disaccharide to 2 monosaccharides and what are the two monosaccharides?

β-galactosidase and galactose and glucose

87

What enzyme is commerically used to remove sugar from egg whites?

Glucose oxidase

88

What enzyme causes the browning reaction in freshly cut apples, pears, peaches, and bananas?

Polyphenyloxidase

89

What enzyme causes hydrolytic rancidity?

Lipase

90

What enzyme catalyzes the conversion of sucrose to glucose and fructose?

Invertase

91

What enzyme can accelerate lipid oxidation?

Lipoxygenase

92

What element is found in proteins but not in carbohydrates?

Nitrogen

93

What do the letters "DE" stand for pertaining to corn syrups?

Dextrose Equivalent

94

What constituent or property of a food does the iodine value measure?

Degree of unsaturation of fats or oils

95

What conditions favor cloud stability in products like tomato and orange juice? a) inactivation of polygalaturonase b) inactivation of PME c) addition of PME

b) inactivation of PME

96

What compound is responsible for the bitterness of orange juice?

Limonine

97

What compound is formed by decarboxylation of histidine?

Histamine

98

What components in milk would be responsible for the causing Maillard browning to occur?

Lactose (reducing sugar) and casein or whey (source of amine)

99

What component of oat bran constitutues the majority of its soluble protein?

Beta glucan

100

What chemical formed during frying of potato products and baking of bread is considered to be a potentially toxic?

Acrylamide

101

What chemical compound is determined as an indicator of Maillard Browning?

Hydroxy methyl furfural

102

What carotenoids contain oxygen?

Xanthophylls

103

What artificial sweetener is also a dipeptide?

Aspartame

104

What are two oligosaccharides that cause flatulence?

Stachyose and raffinose

105

What are three common substrates for the production of hydrogenated fats?

Platinum, Paladium, Nickel

106

What are the two main cell wall constituents of fruits, vegetables, and cereals?

Cellulose and hemicellulose

107

What are the two chemical components of triglycerides?

Glycerol and fatty acids

108

What are the three steps of oxidative rancidity?

Initiation, Propagation, and Termination

109

What are the products of superoxide ion O2- dismutation?

Three (3) O2 and H2O2

110

What are the products of starch hydrolysis having little to no sweetness (D. E. value

Maltodextrins

111

What are the primary products of autooxidation of unsaturated fats?

Hydroperoxides

112

What are the first and second most widely distributed food components?

Water, carbohydrates

113

What are pectinesterases and what do they do?

Split off the methyl groups from protopectin and pectin; Removing the methyoxy groups causes loss of the gel-forming properties and a distinct softening in the structure of the fresh fruit

114

What are pectinates?

Compounds resulting from the combination of pectinic acids or pectins with calcium or other ions to form salts and usually enhance gel-forming capability.

115

What amino acid generally is at the N-terminus of a peptide chain?

Methionine

116

Using the Osborne solubility classification for proteins, what term is used for cereal proteins that are soluble in 70% alcohol?

Prolamines

117

Under what conditions is the formation of lysinoalanine favored in foods?

Alkaline treatment of proteins

118

Under what conditions are zwitterions found?

At the isoelectric point

119

Trans fat occurs naturally in what substance?

Milk fat; adipose tissue from ruminant animals

120

This term describes the pH at which a protein becomes less soluble because it possesses an overall net neutral charge?

Isoelectric point

121

This straight chain, hydroxy fatty acid comprises up to 90% of the total acids in castor bean oil. What is it?

Ricinoleic acid

122

The two polysaccharides that comprise starch are

Amylose and amylopectin

123

The main reason for cooking curds and whey in the manufacture of cheeses by adding milk clotting enzyme is to: kill psychotrophs; kill S. lactis and stop acid production; pasteurize the curds and whey; aid in syneresis

aid in syneresis (D)

124

The lowest boiling component of a mixture of ethanol and water is 95% ethanol and 5% water. What is this called?

Azeotrope

125

The cis isomer of the 9 mono-eno of octadecanoic acid is called?

Oleic acid (the trans isomer is called elaidic acid)

126

Starch is a polymer of which of the following: a.) L-glucose b.) Lactose c.) D-glucose d.) Fructose

C.) D-glucose {anhydro-a-D-glucose units}

127

Splitting the ester bonds in triglycerides can happen at high pH or due to enzymatic reaction. What class of enzymes is responsible for this reaction?

hydrolases

128

Sorghum syrup is often mistakenly called this:

Molasses

129

Sorbitol is best described as a what? a) Dissacharide b) Sugar alcohol c) Organic acid

Sugar alcohol

130

Proteins are made up of about 22 amino acids linked together in chains by

Peptide bonds

131

PCB's are environmental contaminants that can contaminate foods. What does PCB stand for?

Polychlorinated biphenols

132

Name three ketone bodies?

Acetone, acetoacetate, beta-hydroxybutyrate

133

Name the type of water in a food system that is not a solvent, does not freeze, and is very tightly bound to the surface of a molecule.

Monolayer or Type 1

134

Name the type of rancidity which occurs by the hydrolysis of an ester bond to produce a free fatty acid?

Hydrolytic rancidity

135

Name the type of carbohydrate that is formed by the enzymatic cleavage of a starch molecule that results in the formation of a ring structure with a hydrophobic center and a hydrophilic outside edge?

Cyclodextrin

136

Name the two ways to draw sugar monomers?

Fischer, Haworth, Newman

137

Name the pigment responsible for the desirable pink to orange coloring of the flesh of trout and salmon?

Astaxanthin

138

Name the group of polyphenolic antioxidants that occur naturally in fruits and vegetables and in beverages such as tea and wine.

Flavonoids

139

Name the fatty acid that contains 18 carbons and three double bonds?

Linolenic acid

140

Name the amino acids that make up aspartame?

Phenylalanine and aspartic acid

141

Name a food that has a pH greater than 7.0.

Egg white, olives, hominy, chocolate

142

Multiple forms of the same enzyme in a given tissue that arise from genetically determined differences in primary amino acid sequences are called?

Isozymes or isoenzymes

143

Minimum solubility of a protein is at: a) pHpI

b)pH=pI

144

Milk fat globules are surrounded by an interfacial layer called what?

milk fat globule membrane

145

Maltol and ethyl maltol are effective at sparing what common food ingredient?

Sugar

146

Magnesium ammonium phosphate crystals that look like glass and are sometimes found in canned tuna fish are called what?

Struvite

147

Lactase hydrolyzes lactose into what two components?

Glucose and galactose

148

Inulin is a polysaccharide found in some plants. What is the monosaccharide that makes up this polymer?

Fructose

149

In the international Union of Biochemistry system of enzyme nomenclature, the first number identifies what?

General reaction type

150

In surfactants, for what does the abbreviation “HLB” stand?

Hydrophile-lipophile balance

151

In enzymology, what is a turnover number?

Moles converted to product by one mole of enzyme in a given time period.

152

In cottonseed, what does gossypol chelate?

Iron

153

Hydrolysis of a fat by treatment with alkali is called what?

Saponification

154

Humulone and lupulone are two components of what plant added to beer?

Hops

155

How many times more acidic is something with a pH of 2 than a substance with a pH of 6?

10,000

156

How many molecules are in a mole?

6.022 x 10 23

157

How many isomers of a 6 carbon hexose exist?

16

158

How many isomers of a 5 carbon pentose exist?

four

159

How is soybean oil degummed?

Adding 2-3% water, agitating the mixture at about 50°C, and separating the hydrated phospholipids by settling or centrifugation.

160

How is invert sugar made?

The invertase enzyme hydrolyzes sucrose into glucose and fructose

161

How do apocarotenoids differ from carotenoids?

Contain 30 rather than 40 carbons

162

Glucose has 4 isometric carbons. How many stereoisomers does it have?

Sixteen (16)

163

From what amino acid is serotonin derived?

Tryptophan

164

For the D configuration of sugars, which side of the Fisher projection is the reference hydroxyl located?

Right

165

Enzymatic browning is caused by the oxidation of what type of compounds? Name the enzyme.

Phenolics; Poly phenol oxidase (PPO)

166

Degradation of amino acids to aldehydes, ammonia and carbon dioxide through reaction with dicarbonyls produced during Maillard Browning is called what?

Strecker degradation

167

Define water activity.

vapor pressure of water divided by that of pure water at the same temperature

168

Define a zero-order reaction.

It is a reaction which proceeds at a rate independent of the concentration of the reactants

169

Cyanogenetic glycosides are compounds that when treated with an acid or appropriate hydrolytic enzyme, yield what compound?

Hydrogen cyanide (HCN)

170

Compared to sucrose, what is the relative sweetness of saccharin?

Saccharin is 300 times sweeter than sucrose

171

Collagen molecules are rich in what amino acid derivative?

hydroxyproline

172

Certified food colorants can be divided into 2 types. What are they?

Dyes (water soluble) and Lakes (water and oil soluble)

173

Betalain pigments are obtained from what plant source?

Beets

174

Beta-amylase hydrolyzes what type of linkages?

alpha-1,4 glycosidic linkages

175

Benzopyrene or polycyclic hydrocarbons have been identified as carcinogens. What common picnic activity is thought to produce these undesirable compounds?

Charcoal burning or barbequeing

176

Benzene rings with attached methoxyl groups are called what?

Anisole

177

Benzene rings with attached hydroxyl groups are called what?

Phenolics

178

At what temperature range do most proteins denature?

50-60 C

179

At what temperature does a solution of 20% amylose and 80% water boil?

100C it is not a true solution

180

At what aw does oxidation of fats proceed most rapidly: a) 0.3 b) 0.2 c) 0.5 d) 0.8

b) – foods with an aw value of 0.1 or less oxidation proceeds very rapidly

181

Antioxidants like EDTA and citric acid function as antioxidants by reacting with what catalystis of oxidation?

Trace metals

182

Another name for triacylglycerides is?

Triglycerides

183

An exoenzyme that catalyzes hydrolysis of maltose units from the nonreducing end of starch is called?

Beta amylase

184

An example of a saturated fatty acid is the 16 carbon molecule called?

Palmitic acid

185

An enzyme that only catalyzes hydrolysis of alpha 1,6 linkages in starch is called what?

Pullunase (R enzyme) or isoamylase

186

An enzyme that breaks down pectin molecules and causes softening of fruit tissue (avocados, pears, tomatoes, and pineapple) is called?

Polygalacturonase; pectinase

187

All unsaturated fatty acids that contain an isolated cis double bond absorb light at approximately what length?

190 nm

188

Alitame is how many times sweeter than sucrose?

Two thousand (2000) times sweeter

189

A physical change in an amorphous material promoted by the addition of heat and the uptake of low molecular weight substances called plasticizers is called what?

Glass transition

190

What would you expect to happen to the following solutions if they were heated at the same temperature and for the same length of time? A. lysine and sucrose in water; B. lysine and glucose in water

A. Colorless; B. Brown

191

What is the pH of a mixture of strong acids combining 100 ml of pH = 2 and 100 ml of pH = 3?

2.26 (Equal volumes of strong acid: Difference of 1 -- add 0.26; difference of 2 or more -- add 0.3)

192

What is the difference between a competitive enzyme inhibitor and a noncompetitive enzyme inhibitor?

Competitive inhibitors usually resemble the substrate structurally and compete with substrate for binding to the active site of the enzyme. A noncompetitive inhibitor binds to the enzyme outside its active site independent of substrate

193

What is O-R Potential? What does it measure?

Oxidation-Reduction Potential; The tendency of a reversible system to give or receive electrons

194

What is Flocculation?

The redeposition of small dissolved crystals or sol particles into larger crystals or sol particles in an oil-in-water emulsions

195

What do the initials BHT and BHA stand for and what is their use in foods?

Butylated hydroxytoluene, Butylated hydroxyanisole, Antioxidants

196

What are the two sulfur containing amino acids?

Cysteine and Methionine

197

What are the two stages of freezing?

Nucleation; Crystal growth & recrystallization

198

What are the two protein components of Gluten and what is their function?

Glutenin; function = elasticity, Gliadin; function = plasticity

199

What are the H3O+ and OH- concentrations in a solution with pH = 5?

[H3O+] = 10-5 moles/l; [OH-] = 10-9 moles/l

200

What are the five elements found in proteins?

Carbon, oxygen, nitrogen, hydrogen, sulfur

201

What are the 5 most abundant elements in the earth’s crust by weight?

Oxygen, Silicon, Aluminum, Iron, Calcium

202

What are the 3 primary gases in air?

Nitrogen (78%), Oxygen (21%), Argon (1%)

203

What are 3 folic acid rich foods?

Leafy green vegetables, citrus fruits and juices, beans lentils, fortified breakfast cereals

204

What acids would you check for TA in oranges, apples, yogurt, grapes?

Citric, malic, lactic, tartaric

205

What 5 parameters are critical for an extrusion process?

Barrel temperature, screw speed, moisture content, compression ratio

206

To aid in recycling, consumer plastics are given one of seven numbers. Give the number and type of plastic for 4 of these groups.

1 (polyethylene terepthalate), 2 (high density polyethylene), 3 (polyvinyl chloride), 4 (low-density polyethylene), 5 (polypropylene), 6 (polystyrene), 7 (other)

207

The redeposition of small dissolved crystals or sol particles into larger crystals or sol particles in a water-in-oil emulsion is called what?

Ostwald ripening

208

The 3 main polymorphic forms of crystalline fat are alpha, beta prime and beta; put them in order of melting point from highest to lowest

Beta > Beta prime > Alpha

209

Specific tradenames are often used in a generic sense to refer to products. What’s the trade name we almost always call the following: regenerated cellulose, polyamid, and polyvinylidene chloride?

Cellophane, Nylon, Saran

210

Rank the following lipoproteins by size: HDL, VLDL, LDL, IDL, Chylomicrons.

Largest Chylomicrons > VLDL > IDL > LDL > HDL smallest

211

Name three types of enzyme inhibition?

Competitive, noncompetitive, uncompetitive, and suicide

212

Name three types of browning reactions in foods?

Maillard, carmelization, ascorbic acid browning, enzymatic browing

213

Name three products from the hydrolysis of starch by alpha amylase.

Oligosaccharides; Maltodextrins; Maltose; Glucose; Corn syrup

214

Name three gums not from plants?

Gellan, curdlan, xanthan

215

Name three compounds in dietary fiber:

Lignin, hemicellulose, pectin substances, cellulose, gums and musilages

216

Name the two substances that may be used for commercial caffeine extraction?

Methylene chloride, supercritical CO2 or H2O

217

Name the three types of conjugated lipids.

Phospholipids – contain a phosphoric acid molecule and a fat molecule; Cerebrosides – contain a carbohydrate and a fat molecule; Sulfolipids – contain a sulfate radical

218

Name the three basic amino acids?

Histidine, lysine, and arginine

219

Name the principle antimicrobial component of the following: thyme, oregano, cinnamon, cloves

thymol, carvacrol, cinnamic aldehyde, eugenol

220

Name the predominant organic acids in the following products: grapefruit, grapes, oranges, and vinegar

Grapefruit – citric acid; Grapes - tartaric acid; Oranges – Citric; Vinegar- acetic

221

Name 4 carotenoid pigments

B-carotene, capsorubin, canthaxanthin, lycopene, lutein, bixin, norbixin, and crocin

222

Name 3 factors that affect enzyme catalyzed reactions:

pH, temperature, [substrate], [enzyme], ionic strength, activators, inhibitors

223

Name 3 classes of flavonoids?

Anthocyanins, flavonals, flavones, catechins, flavanones

224

Name 3 blood plasma lipid classes

HDL, LDL, VLDL

225

Name 2 hydrocolloids that gel at high temperature:

Methyl cellulose, curdlan

226

List 5 of the major 6 classes of enzymes.

Oxidoreductase, Transferase, Hydrolase, Lyase, Isomerase, Ligase

227

List 3 limitations of using native starch in foods?

Cold water insoluble, Instability at low pH,Cohesive texture, Viscosity breakdown, Amylose, retrogradation, Amylopectin association

228

Give three reasons for adding starch to food.

Coating and glazing agent; thickening agent; colloidal stabilizer; moisture retention; gel forming; binding

229

Give the hydrogenation products of glucose, fructose, galactose, and xylose?

Sorbitol, manitol, glactitol, xylitol

230

Give the 3 main polymorphic forms of crystalline fat

Alpha, Beta prime, Beta

231

For the following saturated fatty acids give the systematic name or molecular formula: palmitic, stearic, acetic.

Palmitic, n-hexadecanoic, C16 H32 O2 Stearic, n-octadecanoic, C18 H36 O2 Acetic, C2 H4 O2

232

What are the components of a plant cell wall?

Pectin, cellulose, hemicellulose, lignin and protein

233

What are the two most abundant fatty acids in peanut oil?

Oleic acid and Linoleic acid

234

Chondrus crispus is the source for what polysaccharide hydrocolloid?

Carrageenan

235

Mixing leeched wood ashes with lard in the presence of heat will create what AND what is the chemical process called?

Soap AND saponification

236

What chemically modified cellulose will form a thermal gel at 55-60ºC but can return to solution at room temperature?

Methylcellulose (or hydroxypropylmethylcellulose)

237

What is Fehling's test used to determine?

Reducing sugars

238

What is the enzyme in saliva that breaks down some starches to maltose?

Ptyalin (or amylase)

239

What is the name of the pickled flower buds of Capparis spinosa, a Mediterranean shrub?

Capers

240

What spice is made from the dried stigmas of the crocus plant?

Safron

241

Where might one find the compound "linalool"?

Spices or herbs

242

Which two amino acids have the highest reactivity in Malliard reactions?

Arginine and lysine

243

What general type of compound is bixin?

Apocarotenoid

244

For what is the natural food color annatto used?

Cheese

245

From what tree is Gum Arabic obtained?

Acacia

246

What is the brand name used by Procter and Gamble for olestra?

Olean

247

Sake is a fermented alcoholic beverage made from what?

Rice

248

What are the six major anthocyanins?

Cyanidin, delphinidin, malvidin, pelargonidin, peonidin, petunidin

249

Accumulation of unwanted material on solid surfaces resulting in decreased function is called what?

Fouling

250

What does the Karl Fischer test measure?

Water concentration

251

What is the soxhlet apparatus used for?

Fat determination

252

What does the Mojonnier Test measure?

Fat in Milk

253

What does the Babcock Test measure?

Fat concentration

254

What does the Kjeldahl measure?

Nitrogen concentration

255

Who worked at the Carlsberg Brewery Laboratory in Copenhagen, Denmark the late 1800s and developed a method to determine nitrogen concentration in organic substances?

Johan Kjeldahl

256

What is the name the test for reducing sugars in foods? What organic groups does the test detect? What color change occurs with a positive test?

Benedict's; aldehydes and alpha-hydroxy-ketones; brick-red precipitate

257

What term is used to describe the relationship between water activity and moisture of food at a given temperature and what is its shape?

Moisture sorption isotherm; Sigmoidal

258

Which of the following chemical bonds is involved in the secondary structure of proteins? Peptide, Glycosidic, Hydrogen, Van der Waals

Hydrogen

259

Luminometry is used to detect the presence of ATP based upon its enzymatically catalyzed reaction with what bioluminescent compound?

Luciferin