Food technology Flashcards

Question

What is the bran?

Answer 1

A technological term for the outer part of a kernel, including fruit wall, seed coat and the aleurone layer, which is really a part of the endosperm but that ends up with the bran in cereal processing

Answer 2

Cellulose, beta-glucan and arabinoxylan which are dietary fibers from the cell walls. Lipids, pigments, metabolic proteins, sugars, minerals, vitamins B & E, phytochemicals (polyphenols)

Answer 3

Starch granules encapsulated in a storage protein matrix

Answer 4

Cardiovascular disease - Diabetes - Weight gain - Colon cancer - Inflammatory related diseases

Answer 5

Metabolic syndrome

Answer 6

Central obesity (bukfetma), high blood pressure, glucose/insulin imbalance (insulin resistance), Dyslipidemia (lågt HDL, höga TG, hög LDL). Associated with increased risk of CVD, diabetes type II, inflammation and some types of cancer.

Answer 7

Carbohydrates that humans can't digest in the small intestine (tunntarmen), that are fermented by bacteria in the large intestine.

Answer 8

Cellulose, betaglucan, arabinoxylan, fructan, pectin

Answer 9

Raw starch is crystalline and not soluble in water. When starch granules are cooked in water, granules swell. Hydrogen bonds within the starch molecules are broken, molecular order is disrupted. Starch forms hydrogen bonds with water. As hydrogen bonds are formed, water is able to penetrate further into the starch granule, which swell more. Amylose leaches out. Swollen granules take up more space and the mixture thickens as the enlarged granules leach amylose (and possibly amylopectin)

Answer 10

Starch reassociates to a more ordered, crystalline structure upon cooling. More likely to occur in a high amylose starch. Water is lost.

Answer 11

Starch granules that are physically inaccessible to enzymes ex. enclosed in cell walls.

Answer 12

Starch granules in natural, granular form

Answer 13

Gelatinized starch granules, cooked and cooled. Starch becomes retrograded & less accessible to enzymes

Answer 14

Starches that have been chemically modified to resist digestion and does not retrograde. Not found in nature.

Answer 15

C18:2, omega-6

Answer 16

C18:1, omega-9

Answer 17

C18:3, omega-3

Answer 18

C20:5, omega-3

Answer 19

C22:6, omega-3

Answer 20

Low molecular weight organic compounds from food plants other than the common nutrients & which have health effects

Answer 21

Asparagine + reducing sugars (high temp)-> acrylamide (CH2=CH-CONH2)

Answer 22

Intermediate length polymers of D-glucose formed from the hydrolysis of starches such as tapioca, potato and wheat. Maltodextrins simulate the viscosity and mouthfeel of fats/oils and are used to reduce the fat content of some foods.

Answer 23

Elastic solid formed upon cooling of a gelatinized starch paste; a two-phase system that contains a solid continuous phase and a liquid dispersed phase.

Answer 24

Resistance to flow of a liquid when force is applied. A measure of how easily a liquid will flow. Thin liquids have a low viscosity. Thick liquids or gels have a high viscosity and flow slowly.

Answer 25

Linear polymers of D-galacturonic acid joined by alfa-1-4 glycosidic linkages. Some COOH are esterified with methanol. Important constituents of plant tissue found mainly in the cell wall.

Answer 26

- Protopectin, found in immature fruits. Insoluble in water. Cannot form gels. High molecular weight. - Pectinic acid, formed by enzymatic hydrolysis of protopectin as a fruit ripens. High-molecular weight pectinic acids are known as pectins. - Pectic acid, shorter-chain derivative of pectinic acid that is formed as a fruit overripens. Incapable of gel formation.

Answer 27

Complex hydrophilic carbohydrates containing 1000's of monosaccharide units, of which Galactose is the most common. Most gums are unable to form gels due to a highly branched structure. However, they are able to trap or bind large amounts of water within their branches. Aqueous dispersions therefore tend to be very viscous, because the molecules become entangled.

Answer 28

The barley grain is soaked and sprouted. When it sprouts it produces an enzyme that hydrolyzes starch to a shorter carbon chain, maltose. Maltose is a fermentable carbohydrate that is used to feed yeast and produce Co2 and alcohol in bread and liquor making.

Answer 29

Protein substances left in the flour after the starch has been removed, which when hydrated and kneaded produce the elastic, cohesive structure of dough.

Answer 30

Chlorophyll (green), carotenoids (yellow, red, orange), anthocyanin (red, blue, purple), anthoxanthin (white)

Answer 31

Fat-soluble, porphyrin ring with Mg at the center, found in chloroplasts. If Mg is removed by prolonged storage, cooking etc, chlorophyll loses colour.

Answer 32

Carotenes and xanthophylls

Answer 33

Fat-soluble, found in chloroplasts and chromoplasts, found mostly in flowers, fruits and roots, conjugated double bonds are responsible for the colour, more conjugated double bonds = deeper colour.

Answer 34

Differs from anthoxanthin in its positively charged oxygen, water-soluble, found in cell sap, colour affected by pH (turns turquoise in alkaline conditions)

Answer 35

White or pale yellowish, water-soluble, found in cell sap, turns brownish grey from prolonged heat.

Answer 36

Polyphenolic compounds that add both colour and astringent flavour. Range in colour from pale yellow to light brown. Tannins in wine & teas contain antioxidant properties correlated with good health.

Answer 37

Climacteric ripens AFTER harvesting (avocado, banana, tomato) Non-climacteric ripens BEFORE harvesting (cherry, citrus, strawberry)

Answer 38

- Chlorophyll degradation reveals carotenoid pigments - Sugar increases - Acid decreases - Ethylene gas produced stimulates further ripening, ex softening of plant cell wall.

Answer 39

Discoloration of some fruits or vegetables when bruised or cut due to reaction between phenolic compounds and enzymes when exposed to oxygen

Answer 40

- Avoiding contact between substrate and oxygen - Covering with film wrap or sugar syrup - Application of citric acid powder to the cut surface means the citric acid is oxidized instead of the pigment. Acidic pH also inhibits enzymatic action. - Blanching destroys polyphenol oxidase enzyme, enabling long freezer storage

Answer 41

Cell membranes lose selective permeability, allowing movement of sugars, some nutrients and water. Diffusion and osmosis occurs as substances move, and the plant cell loses form, water and turgor.

Answer 42

Nutrients naturally present, type of cooking medium, duration of cooking, added substances.

Answer 43

- Pasteurized | - UV irradiation treatment

Answer 44

- Grown without use of chemical pesticides, herbicides or fertilizers - Have verifiable records of their systems of production - Products must be 95 % organically produced

Answer 45

A suggested term for isolated compounds of fruits, vegetables and other foods that are thought to provide health and medicinal benefits to the diet.

Answer 46

Flavour compounds in the genus allium that contain sulfur compounds and offer phytochemical value

Answer 47

Flavour compound of Brassica genus including cruciferous vegetables with sulfur compounds

Answer 48

Zwitterions - amino group and carboxylic group are both ionized and exist as COO- and NH3+. Therefore, amino acids are amphoteric

Answer 49

That it can behave as an acid or as a base in water depending on the pH

Answer 50

They usually precipitate, like in cottage cheese where acid is added to bring the pH to pI for the major milk proteins (casein)

Answer 51

The protein unfolds, but there is no change in amino acid sequence (primary structure)

Answer 52

Heat - pH change - ionic strength (salt conc.) - freezing - surface change

Answer 53

- heating of beaten egg whites to produce meringues - cottage cheese - inactivating enzymes by blanching before freezing

Answer 54

frozen eggyolks are lumpy when thawed because lipoproteins denature and aggregate - overheating can cause denaturation

Answer 55

peptide bonds are broken to form smaller peptide chains | caused by acid or proteolytic enzymes

Answer 56

- ficin, papain & bromelain are used as meat tenderers - too much hydrolysis would make the meat "mushy" - rennet hydrolyzes a specific peptide bond in milk, causing milk proteins to aggregate

Answer 57

the browning of baked products. A free carbonyl group of a reducing sugar reacts with a free amino group on a protein when heated. Affects flavour and colour. Reaction causes loss of lysine, arginine, tryptophan and histidine, as they have free amino groups able to react with reducing sugars. All except arginine are essential.

Answer 58

those that are readily digestible and contain the dietary essential amino acids in quantities that respond to human requirements

Answer 59

one that contains both hydrophilic and hydrophobic sections

Answer 60

a characteristic of a molecule that enables it to perform a specific role in a food, ex. solubility, thickening, binding, gelation, foaming, emulsifying (for proteins)

Answer 61

addition of a dilute salt solution to improve the dispersibility of a protein

Answer 62

addition of a concentrated salt solution to precipitate a protein

Answer 63

the number of charged an polar groups along the protein chain

Answer 64

muscle, connective tissue and fat

Answer 65

- myofibril proteins make up the muscle bundles - stromal proteins (connective tissue proteins): collagen, elastin, reticulin - sarcoplasmic proteins: pigments & enzymes (hemoglobin, myoglobin)

Answer 66

a nerve impulse causes release of calcium ions from the sarcoplasmic reticulum into the sarcoplasm, a jelly-like substance surrounding the myofibrils. Calcium ions bind to actin, enabling reaction with myosin. ATP is needed as energy source for both relaxation and contraction.

Answer 67

this stiffening is due to loss of extensibility by the myofibril proteins actin and myosin, once energy reserves are depleted. Meat cooked while in rigor mortis is extremely tough.

Answer 68

enzymatic breakdown of proteins that hold muscle fibers together. Allows muscles to relax and become soft.

Answer 69

animal is killed - aerobic respiration ceases, blood flow stops - no oxygen supplied to muscle - anaerobic glycolysis continues - lactic acid formed - pH decreases - at pH 5,5 glycolysis enzymes denature - ATP supply depleted quickly - lack of ATP means calcium is not pumped out - actin & myosin bind irreversibly forming actomyosin cross-links - muscle becomes rigid

Answer 70

the pH that is reached when glycolysis ceases, ~5,5. Low ultimate pH inhibits microbial growth and is desired. High ultimate pH binds more water, but has poor m.o. resistance

Answer 71

rapid pH change while the temperature is still high causes considerable denaturation of contractile and/or sarcoplasmic proteins and loss of water-holding capacity. Lysozomal proteins are released at high temp, these cause hydrolysis of proteins. This might happen if the carcass is not cooled rapidly after slaughter.

Answer 72

muscles become tender due to protein & actomyosin breakdown. A protease which is active at around pH 5,5 breaks down the thin myofilaments at the Z-lines. Sarcoplasmic proteins denature and myofibrils denature somewhat, resulting in loss of water-holding capacity. Collagen and elastin do not denature significantly during aging.

Answer 73

hanging the carcass in 2 degrees celsius for 1-4 weeks. Pork and lamb do not require aging since they are young at slaughter.

Answer 74

the predominant pigment and its concentration in the meat. The 2 major pigments in meat are myoglobin and hemoglobin

Answer 75

frequently exercised portions of the animal that expend great amounts of oxygen like chicken legs. more myoglobin in: cows than pigs, older sheep than lambs, bulls than cows.

Answer 76

stores oxygen in the muscles

Answer 77

carries oxygen in the bloodstream

Answer 78

when myoglobin is exposed to oxygen, bright red oxygenated oxymyoglobin is produced. Oxidation of oxymyoglobin or myoglobin results in metmyoglobin.

Answer 79

hydrogen bonds and heat-sensitive crosslinks are broken. some of the tough-structured collagen is then solubilized and converted to gelatin. faster at higher temp.

Answer 80

to preserve colour and inhibit Clostridium botulinum

Answer 81

because muscle fibers exist as short bundles. Also contains less connective tissue, and more of it converts to gelatin during cooking.

Answer 82

the seeds of a pod of the Leguminosae family.

Answer 83

the protein is coagulated and its availability is higher following cooking.

Answer 84

soy milk that has been coagulated to make the gel

Answer 85

a fungus "mycoprotein" produced by fusarium venenatum

Answer 86

72 degrees celsius for 16 s or 62 degrees celsius for 30 min. Cook poultry to 74 degrees celsius.

Answer 87

68 degrees celsius. Cook pork to 68 degrees.

Answer 88

connective tissue layer that surrounds individual muscle fibers.

Answer 89

connective tissue layer that surrounds an entire muscle

Answer 90

connective tissue layer that surrounds muscle bundles

Answer 91

all of the egg's cholesterol - almost all of the egg's fat - contains all known vitamins except vitamin C - triglycerides, phospholipids (primarily phosphatidyl choline/lecithine), sterols (ex. cholesterol) - 40 % of the egg's protein - pigments (mainly xanthophylls, carotene, lycopene) from the hen's feed

Answer 92

60 % of the egg's protein - riboflavin, niacin, biotin - magnesium, potassium

Answer 93

94 % CaCO3 - 1 % MgCO3 - 1 % CaPO4 - 4 % organic matrix

Answer 94

the breed of hen - has no known effect on flavour/quality

Answer 95

the feed given to the hen

Answer 96

contents inside the shell shrink and the air cell enlarges due to water loss - the yolk flattens as the vitelline membrane thins - pH rises from 7,6 to 9,6 allowing bacterial growth

Answer 97

a technique that allows a view of the shell and inside of eggs without breaking the shell - scanning with bright light

Answer 98

eggs are viscous and coagulate, therefore they bind ingredients like in meatloaf, and they bind breading

Answer 99

raw egg whites coagulate around foreign particles in a hot liquid. ex. clarifying soups, bringing stray material to the surface for removal

Answer 100

egg yolks contain phospholipid emulsifiers, including lecithin. Emulsifiers allow two ordinarily immiscible liquids, such as oil and water to mix

Answer 101

egg whites increase 6-8 times in volume when beaten to a foam. as the egg white foam is heated, the protein coagulates around air cells, maintaining a stable foam structure.

Answer 102

a two-phase system of liquids in solids forms as eggs coagulate, forming a gel in custards.

Answer 103

eggs coagulate and thicken mixtures such as custards and hollandaise sauce

Answer 104

the empty space formed at the large end of the egg. holds oxygen. doesn't exist initially. becomes large by age, cooling, moisture loss. can result in microbial spoilage due to oxygen supply.

Answer 105

air movement from ar cell to yolk is minimized

Answer 106

proteins unfold and align in parallell fashion, forming intermolecular bonds, protein chains shrink. the egg becomes opaque when light cannot pass through the protein mass.

Answer 107

the liquid/fluid egg is converted into a solid state (gel). water escapes from the structure as unfolded helices attach to each other. affected by heat, beating, pH, sugar, salt

Answer 108

occurs with long, high heat exposure. formation of ferrous sulfide from sulfur in egg protein and iron from the yolk.

Answer 109

avidin: binds biotin required for some m.o. growth lysozyme: hydrolyzes cell walls of some bacteria conalbumin: binds with the iron of the yolk, preventing growth of m.o. that require iron

Answer 110

protein precipitates, releases water and becomes tough

Answer 111

the disaccharide lactose. carbohydrates constitute about 5 % or less of milk.

Answer 112

it is converted to lactic acid. aged cheese may be digestible by lactose intolerant persons.

Answer 113

carotene and xanthophyll

Answer 114

caseins, about 80 % of milk protein. Alpha-s, beta and kappa caseins.

Answer 115

alpha-s and beta contain several phosphate groups esterified to serine. these are calcium-sensitive and may be coagulated by addition of calcium. kappa-casein has only 1 phosphate-group and is not calcium-sensitive. alpha-s and beta are very hydrophobic. kappa-casein is a glycoprotein containing an acidic carbohydrate section and so is much more hydrophilic.

Answer 116

casein fractions associate with each other and with colloidal calcium phosphate to form casein micelles. alpha-s and beta casein are mostly in the micelle's interior, kappa casein on the outside. Carbohydrate "hairs" protrude from the micelle, and give steric hindrance.

Answer 117

by addition of acid at a pH 4,6-5,2. as micelles approach pI, charge and extent of hydration is reduced, micelles are no longer stable. K-casein carbohydrate "hairs" flatten, reducing steric hindrance. Acid also causes some calcium to be removed from the micelles. They then coagulate

Answer 118

the enzyme rennin cleaves a specific bond in K-casein, causing the charged, hydrophilic "hairs" to be removed from the micelle. The now uncharged, hydrophobic, unstable micelles aggregate to form curds. Curds may be separated from whey and made into cheese!. Does not cause removal of calcium from micelles.

Answer 119

relatively stable, are not denatured by heat at neutral pH unless temperatures are very high and heating is prolonged.

Answer 120

the second protein fraction of milk, makes up about 20 % of milk protein. includes lactalbumins and lactoglobulins. whey proteins are more hydrated than casein and are denatured and precipitated by heat rather than by acid.

Answer 121

B1(thiamin), B2(riboflavin), B3(niacin), B5 (panthothenic acid), B6 (pyridoxine), B12(cobalamine), vitamin C and folate

Answer 122

vitamin A, D (small amounts), E and K (minor amounts)

Answer 123

calcium 1/3 in solution, 2/3 colloidaly dispersed. Phosphorus, Cl, Mg, K, Na, S

Answer 124

excessive pasteurization temp - certain animal feed ex wild onions, lipase activity causing rancidity of fat unless destroyed by pasteurization - oxidation of fat or phospholipids by enzymes - light-induced flavour changes in proteins and riboflavin because riboflavin acts as a photosynthesizer - stage of lactation of the cow

Answer 125

destruction of pathogenic bacteria, yeasts and molds as well as 95-99% of nonpathogenic bacteria - vitamin destruction and protein denaturation are minimal

Answer 126

absence of the enzyme alkaline phosphatase which is destroyed at temperatures and times required for adequate pasteurization. If substrate is added, milk turns blue if there is enzyme activity. otherwise, milk stays white.

Answer 127

the use of sterilization temperatures (138-150 C) in combination with the use of presterilized containers under sterile conditions

Answer 128

to prevent creaming (rising of fat to surface) - mechinally increases the number and reduces the size of the fat globules - permanently emulsifies

Answer 129

as the surfaces of many new fat globules are formed, each fat globule becomes coated with a part of the lipoprotein membrane and additional proteins from casein and whey

Answer 130

live m.o. administered in adequate amounts which confer a beneficial health effect on the host

Answer 131

nondigestible carbohydrates that act as food for probiotics. whole grain, banana, onions, garlic, honey

Answer 132

milk is churned (agitated, emulsion breaks, fat coalesces and water escapes) to form water and buttermilk

Answer 133

the high-fat component separated from whole milk as a result of the creaming process

Answer 134

a food produced by freezing while stirring a pasteurized mix containing dairy products

Answer 135

lactose is fermented by lactase to lactic acid. fat is hydrolyzed by lipase. protein undergoes mild hydrolysis to a.a. by rennin.

Answer 136

cottage cheese, cream cheese, feta, ricotta

Answer 137

cheddar, parmesan, swiss cheese (holes from gas-producing bacteria!)

Answer 138

camembert, brie (mold sprayed onto surface) | roquefort (inoculated internally with penicillium roqueforti)

Answer 139

add or modify flavour, texture, areate batters and doughs, contribute flakiness, contribute tenderness, emulsify, transfer heat, such as in frying, prevent sticking, provide satiety

Answer 140

monoglycerides and diglycerides (emulsifiers), triglycerides(most fat)

Answer 141

contain two fatty acids, in place of the third fatty acid is a polar group containing phosphoric acid and a nitrogen-containing group. the most common is lecithin(phosphatidylcholine)

Answer 142

antioxidants in fats (most vegetable oils) that help prevent oxidative rancidity. sources of vitamin E. partially removed by the heat of processing.

Answer 143

steroid with 8-10 carbon side chain and an alcohol group

Answer 144

long hydrocarbon chains with a methyl group at one end of the chain and a carboxylic acid group at the other. most contain an even number of carbons (4-24). trans double bonds have a higher melting point than cis. almost all naturally occuring fats and oils used in food exist in cis configuration

Answer 145

molecular movement slows down - molecules are attracted to each other by van der Waals forces. fat molecules align and bond to form crystals.

Answer 146

alpha, beta-prim, intermediate, coarse beta

Answer 147

smallest and least stable. formed if fats are chilled rapidly

Answer 148

small needlelike, 1 micrometer long. smooth texture

Answer 149

3-5 micrometer in size

Answer 150

25-100 micrometers in length and have the highest melting point.

Answer 151

polymorphism

Answer 152

is favored by rapid cooling with agitation. desirable if a fat contributes aeration to a food. more likely with heterogenous fat.

Answer 153

if cooling is slow. more likely with homogenous fats.

Answer 154

chain length, degree of saturation, isomeric configuration

Answer 155

contains both liquid oil and solid fat crystals. consistency depends on the ratio of solid to liquid triglycerides.

Answer 156

``` hydrolytic rancidity (triglycerides react with water and free their farry acids from glycerol. catalyzed by heat and lipase ex. found in butter). oxidative rancidity (fat is oxidized and decomposes into volatile, stinky shorter carbon chains like fatty acids, aldehydes, ketones. catalyzed by heat, light, iron, copper, lipoxygenases) ```

Answer 157

long-chain polymers, principally carbohydrate, that thicken or gel in aqueous systems, creating the creamy viscosity that mimicks fat. ex. hemicellulose, beta-glucans, microparticulates etc.

Answer 158

a bulking agent created by the random polymerization of glucose, sorbitol and citric acid (89:10:1), substitute for either fat or sucrose.

Answer 159

Pasta, breakfast cereals, snacks like cheese doodles

Answer 160

Mechanically strong, yellow, translucent

Answer 161

Remains in shape, elastic, give a firm bite, non-sticky, cooking water free of starch

Answer 162

Durum wheat or hard wheat which is high in protein content, intact starch granules give less sticky pasta, high carotenoid content for nice colour, low lipoxygenase activity

Answer 163

Lipoxygenase degrades carotenoids which leads to loss of colour and affected flavour

Answer 164

Flour is mixed with water (35-45 C) at a ratio of 3:1. The dough is extruded and the extruder die determines the shape of the pasta

Answer 165

To be stable in storage in room temperature

Answer 166

31% to under 12,5 %. Not too dry, pasta might crack. Too slow drying can lead to spoilage due to mold growth

Answer 167

Dry and liquid ingredients are mixed and churned through a screw towards an extruder die. High pressure and heat are generated. As the dough flows out through the nozzle, pressure is released, temperature cools, and as moisture evaporates the dough expands and starch solidifies

Answer 168

The grain must be cooked to degrade starch granules. A large sudden drop in temperature and pressure gives puffing

Answer 169

Preservation of food through formation of inhibitory metabolites such as organic acid (lactic acid, acetic acid, formic acid, propionic acid), ethanol, bacteriocins, etc., often in combination with decrease of water activity (by drying or use of salt) • Improving food safety through inhibition of pathogens or removal of toxic compounds • Improving the nutritional value • Organoleptic(sensory) quality of the food

Answer 170

Vitamins in bran have low bioaccessibility which can be increased, phytic acid can be inactivated, fibres can be solubilized which is good for blood glucose and gut bacteria, gluten can be degraded etc.

Answer 171

Color, alcoholic strength, foam, carbon dioxide, bitterness, astringency

Answer 172

Water, malt, hops and yeast

Answer 173

Steeping, germination, kilning(drying)

Answer 174

Water content in barley grains is increased up to 44 %

Answer 175

Enzymes are activated

Answer 176

Water content is decreased, enzyme activity inhibited, color development. The higher temperature, the more colour, the less enzyme activity.

Answer 177

To uncover starch in endosperm by activating enzymes, decomposition of cell walls and protein matrix, and to give enzymes, fermentable carbohydrates and colour

Answer 178

less amylases

Answer 179

Grinding, addition of water and adjunct, mashing, filtration, addition of hops, wort boiling, filtration, cooling

Answer 180

The wort is boiled with hops. Bitter (α-acids) and aromatic compounds are extracted. Volatile compounds evaporate. Enzymes are destroyed. The wort becomes sterilized. A precipitate of denatured protein is formed.

Answer 181

Yeast is added and beer is fermented

Answer 182

Low demands on climate and soil, hulls stick to kernel, uniform kernel size, short dormancy time, high and even germination capacity, high extract starch yield, high enzyme activity, low protein content, low beta-glucan content.

Answer 183

During steeping, water uptake will depend on kernel size. For uniform degree of germination kernels need to be similar in size.

Answer 184

Helps with degradation of proteins and cell walls during mashing

Answer 185

More proteins means more issues with cloudiness

Answer 186

Because beta-glucan gives high viscosity in solution which is not desirable in beer

Answer 187

Tannins, CO2, bitter compounds from hops, esters, amino acids

Answer 188

Proteins, alfa-acids, beta-glucans

Answer 189

Bitter taste from oxidized phenols, flat taste due to low CO2, cloudiness from proteins or beta-glucans that are not dissolved, bacteria can give lactic and acetic acids (vinegar!)

Answer 190

Paddy rice is soaked, steamed and dried, and then dehulled to produce parboiled brown rice. It can also be milled to get rid of the bran for white parboiled rice.

Answer 191

Low in amylose and high in amylopectin and thus sticky

Answer 192

High in amylose and low in amylopectin and thus less sticky

Answer 193

More resistant to breakage due to starch gelatinization, better nutritional value especially for B-vitamins, less tendency to become sticky during cooking

Answer 194

Hard wheat has much higher protein content and forms much better gluten structures. Hard wheat has higher water absorption ability. Proteins in hard wheat are tightly packed and strongly bound to starch. In soft wheat, proteins are loosely aggregated and not bound to starch. Hard wheat is used for bread, soft wheat for cakes.

Answer 195

Short monomeric molecules that absorb much water, are cohesive and not resistant to extension.

Answer 196

Long linear monomeric molecules that form huge polymeric networks with interdisulphide bridges and H-bonds. Highly resistant to extension.

Answer 197

strengthens gluten, gives more stretching ability, volume and texture, controls fermentation, adds to taste and flavour, increases shelf life

Answer 198

Starch slowly absorbs water. Gluten network is built during mechanical kneading and resting. Fat lubricates the gluten and gives more elasticity to the dough. Air is incorporated which decreases density.

Answer 199

Primarily glutenins and gliadind (80%). Starch, lipids and fibers are minor components.

Answer 200

water and mechanical energy is added to the flour

Answer 201

Dehydration of outer parts of the dough along with Maillard reaction gives browning at high heat.

Answer 202

about 60 degrees celsius.

Answer 203

Redistribution of humidity between crumb and crust leads to dryness and loss of crustiness. Loss of softness. Change in smell and taste.

Answer 204

Hard wheat, high protein content, good falling number (250-300), high amount of damaged starch granules for water absorption and enzyme exposure, certain combination of gliadins and glutenins, low protein charge, high amount of glutamine for hydrogen bonds, high amount of cystein for disulphide bonds

Answer 205

Bran fraction may cut the gluten strands, germ oil may shorten the gluten strands.

Answer 206

Easier to mix, more stable after fermentation, shortens gluten strands which gives tender finer softer crumb structure, larger volume, decrease water loss, softer crust, flavour, slower staling

Answer 207

Water absorption is reduced, volume lower, often collapses after baking, raises starch gelatinization temp, lower water activity for fermentation

Answer 208

Flour, protein content and quality, yeast, yeast nutrients, emulsifiers, proofing process, baking process

Answer 209

flour, mixing time, punching, fermentation

Answer 210

sugar content, final proof, baking

Answer 211

sugar content, storage conditions of the bread

Answer 212

volume, crumb structure, added improver, humidity of the crumb

Answer 213

sugar, fat and water . Hard to rise without baking soda.

Answer 214

sugar and fat, and low in water. Gluten development is not desired. No starch gelatinization.

Answer 215

Lipids melt. Dissolution of sucrose. Volume increase. Starch does not gelatinize. Cookie spreads until viscosity is too large. Surface cracks. Moisture is lost from surface. Concentrated sugar crystallizes.

Answer 216

those animal tissues that are suitable for use as food

Answer 217

Traditional (red and intermediate): beef, pork, lamb, mutton, goat etc. Poultry: chicken, turkey, duck, geese Fish: shellfish and finfish Game meat: flesh of any non-domesticated animal

Answer 218

Intra-muscular fat(marbling), inter-muscular fat, abdominal fat.

Answer 219

Colour, tenderness, water holding capacity (WHC), flavour and odour

Answer 220

Concentration of pigments. Chemical states (Fe2+/Fe3+). Light-scattering properties of meat(meat structure). Preharvest and postharvest factors.

Answer 221

Diet: Grazing gives beta-carotene in fat (yellowish). Restricted feeding promotes oxidative metabolism, reduces glycogen storage which gives higher pH and darker meat. Vitamin E increases lipid stability and improves colour. Physical activity affects muscle type and metabolism. Breed, halothane and ryanodine genes in pork. CO2 or electrical stunning method.

Answer 222

Pale, soft, exudative meat. Depends on fast pH decrease, can reach 5,5 in 45 minutes while the carcass is still warm. Will cause denaturation of muscle proteins which makes meat paler. Pigs more often affected. Carriers of the halothane gene are especially sensitive. WHC low -> soggy meat. Depends on unusually quick breakdown of glycogen into lactic acid.

Answer 223

Dark, firm, dry meat. Due to loss of glycogen before slaughter, ultimate pH is high. Glycogen lost because of physical activity before slaughter or long starvation period. Higher ultimate pH means less inhibition of m.o. Cattle and sheep more often affected. Muscles hold more water.

Answer 224

MAP (modified atmospheric packaging). CO2 inhibits aerobic bacteria. Low conc of O2 leads to irreversible browning. 65 % O2 makes for nice colour.

Answer 225

reversibly binds ligands.

Answer 226

Oxymyoglobin. Ligand O2, colour red.

Answer 227

metmyoglobin. Brown. Ligand H2O. Comes from low oxygen pressure or prolonged storage.

Answer 228

NO binds as ligand, forming nitrosomyoglobin. When the meat is cooked, it is turned into nitrosylhemochrome as globin protein denatures.

Answer 229

Is forms HNO2, nitrous acid, which is in equilibrium with N2O3. N2O3 together with a reducing agent, such as ascorbic acid, can form reduced nitric oxide. Nitric oxide can react with myoglobin, binding in as a ligand on the 6th site!

Answer 230

Denaturation of oxymyoglobin and deoxymyoglobin into red ferrohemochrome which can be oxidated to the brown ferrihemochrome, or formation of ferrihemochrome from oxidated metmyoglobin.

Answer 231

Muscle fiber diameter and sarcomere length is important. Longer sarcomeres are softer.

Answer 232

early postmortem glycolytic rate, ultimate pH, postmortem ageing temp, carcass position and suspension.

Answer 233

How much tissue is there? Collagen, elastin. Collagen can partly be degraded into gelatin.

Answer 234

With age more mature cross-links develop, these are heat-stable and not easy to break down during heating. Rapidly growing breeds have more tender meat. Late maturing breeds slaughtered at early stage are more tender.

Answer 235

Adipose tissue deposits between intramuscular connective tissue strands.

Answer 236

Ageing, cooking, tenderizing enzymes, mechanical tenderization

Answer 237

80-85 degrees C minimum.

Answer 238

The ability of meat to retain its water or added water during the application of external forces such as heating, cutting, grinding or pressing.

Answer 239

Low WHC = less weight = lower profits. Affects colour, texture, juiciness. Accumulation of water in packaging is not appealing to consumers. Water soluble proteins may escape in lost water.

Answer 240

Bound to hydrophilic groups on the meat proteins, immobilized by capillary action between myofibrills and free water.

Answer 241

Water that comes out when applying a little force. Weep: when cut. Drip: during thawing. Shrink: during cooking.

Answer 242

loose water to physically held water

Answer 243

WHC is lowest in the isoelectric point at about 5,1. Here there is poor water binding, no repulsions between myofibrills and water can escape.

Answer 244

To increase charges to increase WHC. Used ex. in sausage production.

Answer 245

Fatty tissues, volatile and non-volatile flavour compounds, compounds degraded and formed in cooking such as carbonyls, furans, pyrazins, diet of animal, hormones in male pig

Answer 246

Pyrolysis of amino acids, Maillard reactions from amino acids and reducing sugars, caramelization of sugars.

Answer 247

How much is produced, and the odour threshold.

Answer 248

More sugar for yeast to ferment means more volume, taste, colour, decrease falling number if it is higher than desired, can be added for storage to prevent degradation as shorter chains are less prone to form crystalline structures.

Answer 249

We form and break interactions between gluten proteins.

Answer 250

The dough relaxes into new gluten conformations.

Answer 251

Salt strengthens the interactions within the protein as it is, gluten can still be formed but needs more kneading.

Answer 252

It stabilizes the gluten network.

Answer 253

Although rye contains more total protein than wheat, it is lower in prolamins and glutelins. A lot of arabinoxylan(fibre) in rye interferes with gluten formation by coating the proteins, decreasing interaction between them. Bran also interferes with gluten formation.

Answer 254

Specific bacteria which are added to raw milk. These produce lactic acid through fermentation, which inhibits growth of other m.o. as well as contributes to taste and other specific characteristics. Starters affect: - Taste - Curdling - Rennet activity during coagulation - Gel firmness and cheese yield - Cheese consistence

Answer 255

Mesophilic have a temp optimum around 20-30 degrees and produce sour milk. Thermophilic have a temp optimum at 40-45 degrees and produce yoghurt.

Answer 256

``` DiacetyLactis - produce both lactic acid and diacetyl. Produce a lot of aroma compounds. CO2 as a residual product contribute to holes in cheese. • Hard/semihard cheese • Sourmilk • Fermented butter • Creme fraiche • Buttermilk ```

Answer 257

Lactis, produce mainly lactic acid. Lower CO2 production. Used in fermented cream (gräddfil), cottage cheese.

Answer 258

``` Lower amount of lactic acid produced, no CO2. • Cheddar cheese • Mozzarella • Camembert • Feta cheese ```

Answer 259

``` Produce lactic acid and acetaldehyde. No CO2 production. • Yoghurt • Mozzarella • Camembert • Feta ```

Answer 260

non-starter lactic acid bacteria. House microflora that are present in milk after pasteurization.

Answer 261

``` Cheese maturation - Break-down peptides from amino acids - Introduces flavours that can give specific character Impact on starter cultures - Competition for nutrition - Might cause lysis of starter cultures Inhibits deteriorating bacteria - Production of antimicrobial - Competition for nutrition Might be destructive - Can produce gas - Unwished flavour ```

Answer 262

``` Low pasteurised milk with specific fat content Vacuum treatment / evaporation Homogenisation Heat treatment 95°C, 5-10 min Chilling to 40°C for yogurt or 20°C for sour milk Inoculation and incubation • yogurt cultures – thermophilic • Sour milk cultures – mesophilic Chilling to 6 – 10°C Packaging ```

Answer 263

• Substance that together with acetoin gives sour milk its taste

Answer 264

Taste of butter. Substance that together with diacetyl gives sour milk its taste

Answer 265

Taste and | aroma of yogurt

Answer 266

Starters added at 20 degrees also include yeast, candida kefir, that produces low levels of alcohol.

Answer 267

* Drying * Salting * Curing * Smoking * Pickles * Hermetization * Fermentation * Heat treatment * Freezing

Answer 268

+ Extended shelf life + Low pH inhibits the growth of other organisms + Protection against lipid oxidation

Answer 269

- Good culture medium for | yeast and fungi

Answer 270

pasteurization and blanching

Answer 271

conservation

Answer 272

To inactivate enzymes and eliminate microorganisms.

Answer 273

``` • Inactivate enzymes before freezing • Eliminate off-flavors • Shorter boiling time – precooking • Water soluble compounds (vitamins, colour, sugars) will be affected ```

Answer 274

Time (min) needed to kill 90% of specific bacteria in specific media under specific temperature

Answer 275

* Over boiling * Changes in texture * Changes in taste * Changed nutritional values

Answer 276

– all pathogens and toxin developing organisms are killed (116 – 121 °C)

Answer 277

* Heat penetration (rate) * Type of foods (high protein, fat, sugar – longer time) * pH (low pH – longer temp) * Composition * Size and shape of the can * Material * Stirring

Answer 278

1. To increase shelf life by acting as a barrier to moisture, oxygen, ethylene, carbon dioxide, volatile aromas, and other compounds whose loss or addition would lead to deterioration. 2. To impart improved handling characteristics, such as the ability to bend more easily without breaking. 3. To improve appearance through increased gloss and color. 4. To serve as a vehicle for added ingredients such as flavors, antioxidants, antimicrobials, etc. 1. To increase shelf life by acting as a barrier to moisture, oxygen, ethylene, carbon dioxide, volatile aromas, and other compounds who would be loss or who lead to deterioration 2. To improve appearance through increased gloss and color 3. To serve as a vehicle for added ingredients such as flavors, antioxidants, antimicrobials, etc

Answer 279

Hardening due to crystallization of fats – Vitamin C is lost during storage – Not all foods can be chilled (chilling injury)

Answer 280

◦ The temperature difference between the food and the freezing medium ◦ The thermal conductivity of the food ◦ The distance that the heat must travel through the food (size and shape of the pieces) ◦ The insulating effect of the boundary film of air or water surrounding the food

Answer 281

– intracellular crystallisation • Water moves out from the cells • Cells will shrink • Damage caused by crystals on the cell surface

Answer 282

The main effect is damage due to big crystals formed during slow freezing rate Ø Broken compartmentalisation (cell membranes) Ø Enzymes and substrates reach each other easier Ø Drip loss will increase the loss of water soluble substances, e.g. vitamins and minerals

Answer 283

Application of heat under controlled conditions to remove the majority of the free water normally present in a food by evaporation - reduction of aw

Answer 284

* Microbial- and insect control * Inhibits sprouting of potato and onions * Sterilisation of food for hospitals

Answer 285

Concentration of solutes cause i.e. increase of sweetness Concentration of compounds at the surface may cause formation of a hard impermeable skin. (it reduces the further rate of drying). Open porous structure of dried food allows access of oxygen - may result in rancidity development

Answer 286

about 50 % of Ca found in milk. To deliver Ca to calf.

Answer 287

calcium phosphate nanocluster bonds in which phosphorylation of serine connect two serine residues on different caseins via clusters of calcium and phosphate. Polymerization can also occur through hydrophobic interaction.

Answer 288

Heat treatment denatures the globular protein and reveals a thiol group (SH) which is reactive and binds to S in other beta-globulins or K-casein, forming threedimensional structures on the outside of micelles.

Answer 289

* Lactation stage (PL/PG higher at the end of lactation) * Parity (PL higher for older cows) * Environmental factors (PL higher in fall/winter) * Feeding (reduced PG by feeding alpine hay)

Answer 290

``` • Lower the cheese quality – Poor clotting properties – Reduced curd firmness • Break down of β-casein - bitter-taste • Increased losses of protein in whey • Faster gelation in UHT milk ```

Answer 291

``` • Sensory quality of specific cheeses – Emmental: cheese ripening – Swiss cheese: typical flavour – Cheddar: sensory quality without bitter taste ```

Answer 292

Caseins and whey. betaglobulin (binds retinol) and alfa-lactalbumin(involved in milk synthesis).

Answer 293

plasmin is a proteolytic enzyme which cuts beta-casein into protease peptones and gamma-casein. protease peptones are lost into the whey and the cheese yield is lower. however this can give some special flavours to the finished cheese which is desirable in ex. emmentaler and cheddar.

Answer 294

Separation of cream and skim milk, homogenization of fat, standardization (putting fat back in) and pasteurization

Answer 295

Skim milk and cream (35 % fat) are separated at 55 degrees. Also removes bacteria and other impurities.

Answer 296

Big fat globules are fragmentized into smaller ones by high pressure through a mesh. Proteins bind to the surface of the small fat globules and prevent them from coalescing.

Answer 297

All amount of milk is homogenized and used in yoghurt, sour milk etc. Better stability and viscosity.

Answer 298

More sensitive to light and lipase activity.

Answer 299

+ No creaming + Even fat distribution + Whiter colour + Fuller taste

Answer 300

Plasminogen, an inactive proenzyme, exists in the blood and can diffuse to milk. Plasminogen activator inhibitor is destroyed in pasteurization, activating plasminogen activator, which turns plasminogen into plasmin.

Answer 301

Mixing of certain amount of skim milk and homogenized fat, as well as vitaminization with vitamin D. Vitamin A is added to spreadable butter products like bregott.

Answer 302

``` Milk is heated to 72 °C for 15 s • Bacteria and virus are eliminated • Enzymes affecting quality are inactivated • Lipase activity is eliminated • The shelf life is prolonged ```

Answer 303

``` Sedimentation § Fat separation § Brown colour § Gel formation § Bitter taste ```

Answer 304

The water in the milk is reduced to <60% via evaporation/boiling under pressure

Answer 305

Sweetened – sugar as preservation agent (62 – 65% sugar) | Non sweetened – needs to be sterilised

Answer 306

1. Evaporation 2. Homogenisation 3. Chilling 4. Condensation tank 5. Caning 6. Sterilisation 7. Packaging 8. Heating 9. Aseptic packaging

Answer 307

* Spray drying | * Roller/drum drying

Answer 308

* Raw milk – butter milk, condense milk, whey powder * Fat – cream; vegetable fats * Sugar - sucrose, glycose, fructose * Firming agents * Emulsifiers (allowed to mix fat and water) * Stabilisers (right consistence also after towing to eat-temperature) * Flavours - vanilla, strawberry jam, cocoa

Answer 309

• Disaccharide – 2 monosaccharide molecules – D-galactose + D-glucose • Connected via ß-1,4-glucose bond

Answer 310

• Sweet taste without aftertaste • Increases storage stability due to low hygroscopicity • Slower reabsorption than sucrose and glucose - suitable for diabetics • Does not cause carries to the same extent as sucrose

Answer 311

``` • Milk powder: Pure solubilisation due to high lactose content (37-50%) • Ice cream: Concentrated lactose forms crystals - gives sandy mouth feeling ```

Answer 312

``` • lactose is not broken down to Glc + Gal by lactase • lactose can not be absorbed by the small intestine and ferments in the large intestine – Gas formation – Vomiting – Diarrhoea – Colic pain ```

Answer 313

• Congenital lactase deficiency: Rare condition that runs in families and is found in new-born babies • Primary lactase deficiency: Increasing age decreases the ability to synthesize lactase. The most common cause • Secondary lactase deficiency: shortage of lactase caused by a problem in the small intestine – Can occur at any age – Might be the result of another condition • Small intestine surgery • Taking certain medication

Answer 314

• Low lactose milk – less than 1 % lactose - Enzymatic hydrolyses with lactase • Lactose free milk drink – below 0,01 % lactose - Chromatography - Ultrafiltration Chromatography – size exclusion chromatography. The lactose molecules are smaller than the milk protein molecules – go slower through the chromatography column and can be separated from the milk Ultrafiltration – membrane based technique. The membrane separates molecules with specific size

Answer 315

``` Saturated – lower during out door period Unsaturated – higher during out door period Polyunsaturated – can by affected by concentrates ```

Answer 316

4-16C – are synthetized in milk cells 16C – transferred from blood and synthesised in milk cells >16C – transferred from blood Trans fatty acids– are synthetized in rumen

Answer 317

• Feed and seasonal variation • Out door period – more unsaturated fat • Milking interval • Lower fat content when more frequent milking • Genetic variation • Differences between breeds • Differences between individual animals within breeds • Lactation stage • Larger fat content synthetized in the udder in the later stage of lactation • Lactation number (age) • More saturated fat in the later lactation

Answer 318

Vit. A,D, E, K, carotenoids

Answer 319

Chemical reaction between oxygen, metals and polyunsaturated fatty acids -> off flavour • Oxidation taste • welpapp, metal • Spontaneous oxidation: affected by feed, late lactation, lack of antioxidants – vitamins and selenium • Induced: affected by light, metals • Aldehydes and ketones - secondary oxidation products - > markers for oxidation

Answer 320

Lipoprotein lipase (LPL) - Endogenous – occurs in blood, saliva, udder- and adipose tissue - In milk, normally associated to casein micelles, but also to MFG membranes - Regarding specific lipases – the activity requires presence of apoprotein - Exogenous – microbial origin in milk

Answer 321

- Milking frequency (increased; MFG are more instable) - Udder health - Lactation stage (Increased in late lactation) - Out door period (decreased) in-door period (increased) - Hormonal balance

Answer 322

- Machine/robot milking, AMS – higher lipolysis - Milk pumping; air bubbles break down MFG - Homogenisation - Temperature

Answer 323

``` • >80% milk fat – The legislation regulates the water content - < 16% • Average composition of Swedish butter • Saturated fat 52 g • Monounsaturated fat 21 g • Polyunsaturated fat 2 g • 20 litre milk (4%) gives 1 kg butter ```

Answer 324

• The texture is one of the most important quality parameters of the butter – spread-ability – mouth feeling – visual parameters • The texture is determined by the ratio between liquid and crystalline fat

Answer 325

• Cultured butter - created by adding live bacteria cultures to the butter before it's churned • Richer in aroma compounds (diacetyl) • The cultures might help with digestion • Sensitive for oxidation • Regular butter - cream that just goes straight to the churning machine • Salted & extra salted butter - Historically preservative effects

Answer 326

1. Cream (35% fat) 2. Heat treatment (3-5 s, 85-90°C) – Enzymes, lipases and microorganisms are destroyed 3. Starter cultures are added - Alternatively, LAB flavour concentrates of are added to the butter kernels 4. Aging - Designed to give the fat the required crystalline structure (20 h if starters are added) 5. Churning - The cream is violently agitated to break down the MFG causing the fat to coagulate into butter grains

Answer 327

6. Separation - Thus the cream is split into two fractions: butter grains and buttermilk 7. Washing of butter grains (optional) - It used to be common practice to wash the butter after churning to remove any residual buttermilk and milk solids but this is rarely done today 8. Working end salting - Working is required to obtain a homogenous blend of butter granules, water and salt - During working, fat moves from globular to free fat - Water droplets decrease in size during working and should not be visible in properly worked butter 9. Packaging - The still warm butter is discharged into the packaging units 10. Cold storage - At least 1-3 days before distribution - Shelf life ca 12 weeks in refrigerator (+8°C) - Can be frozen (-20°C)

Answer 328

* Somatic cell count * Total bacterial count * Spores * Antibiotics * Freezing point

Answer 329

Indicates the udder health and milk quality of the herds – Healthy udders 50-100 000 cells per ml – Good udder health in the herd <150 000 cells per ml in bulk milk

Answer 330

* Milk composition is changed * Lower cheese yield * The fermenting ability is decreased

Answer 331

– Milking hygiene – Cleaning of milking systems – Correct cooling of raw milk

Answer 332

1. Animal: Infectious diseases 2. Farm: Soil, feed, manure, bedding, human, milking equipment, water 3. Transport: Bulk truck, chauffeur 4. Dairy: Water, equipment, employees, starter cultures, rennet, additives 5. Stores and consumers: Incorrect handling and storage

Answer 333

``` – Bulk is not chilled enough – Errors in milking system – Poor water quality – Poor udder health ```

Answer 334

– Bacterial growth in milking system/bulk – Poor heat water capacity

Answer 335

Bacteria that are capable of surviving or even thriving in extremely cold environment. Most are killed by pasteurization; however, they can be present in milk as post-pasteurization contaminants due to less than adequate sanitation practices. Below 4 degrees celsius hardly any growth within 24 hours

Answer 336

• Heat tolerant enzymes are produced if bacterial counts are high • Specific microbes are extremely heat resistant • Enzymes from psychotrophs might cause quality problems • Are not inactivated by pasteurisation • Are still active in the pasteurised product

Answer 337

– Bacillus cereus | – Clostridium thyrobutyricum

Answer 338

* Aerobe soil bacteria * Contaminates milk via dirty tits * Can grow and build spores in milking systems * Common during outdoor period * Might cause contamination in dairy plants * Can grow in consumption milk; lowers the shelf life * Cause sweet curding, and broken cream

Answer 339

B. cereus in pasteurized milk stored under refrigeration conditions produces a chymosin-like protease enzyme which is responsible for degradation of casein, resulting in coagulation (sweet curdling) and finally a bitter-tasting product

Answer 340

The outgrowth of clostridial spores present in milk cause butyric acid fermentation, the late-blowing defect in cheese • Can create considerable loss of product, especially in the production of hard/semihard cheeses like Grana and Gouda • Occur from poor quality silage, most common during the indoor period • Lactic acid à Butric acid + CO2 + H2

Answer 341

• Contributes to increased levels of total count • Occur on the skin (udder/tits), in the udder, farmers hands etc. • Eliminated by pasteurisation • Leads to increased levels of somatic cells and unwished changes in milk quality • Quality of processing is lowered, lower cheese yield, undesirable sensory quality of fermented products

Answer 342

• Decreased activity of starter cultures • The coagulation properties of milk are decreased • Lowered cheese yield (lower casein content, the casein is lost into the whey) • Slower cheese ripening • Decreased product quality (defects in taste and structure)

Answer 343

• Decreased activity of starter cultures • Taste defects (free fatty acids, oxidation) • The production of aroma compounds (diacetyl) is lowered

Answer 344

``` • Decreased activity of starter cultures – Decreased acid formation – Decreased diacetyl production • Decreased viscosity - Deviant protein composition ```

Answer 345

``` – High levels of total bacteria • Poor cleaning of milking system • Poor cooling of milk ```

Answer 346

The smell of stable caused by specific bacteria

Answer 347

``` – Reaction between milk fat and oxygen • The content of feed pro- and antioxidant content in feed • The milk fat composition ```

Answer 348

``` The milk fat quality • The type of milking system • Lactation stage • Feed ```

Answer 349

Feed via air

Answer 350

``` Chemicals in the environment • Products for tits washing • Salves • Rubber/plastic parts in milking equipment ```

Answer 351

Consumers security – acute allergic reactions or hypersensitivity Technological problems; fermentation is inhibited Bacterial resistance

Answer 352

Base values (råvaruvärde) = price for milk with 4,2 % fet and 3,4 % protein A conto price = Base value plus bonus for higher quality (4% of base value)

Answer 353

``` Eco, season (more valuable in summer), • Fat and protein - Base 4.2% (fat) and 3.4% (protein) - Higher/lower 2.4 öre/0.1% fat - Higher/lower 6.0 öre/0.1% protein Somatic cells, bacterial count, spore count ```

Answer 354

Rennet cheese but not acid cheese

Answer 355

Hard(parmesan), soft and semi soft(brie, feta), fresh(philadelphia), cheese spreads (kavli)

Answer 356

* Standardisation of fat * Pasteurisation * Bactofugation and microfiltration * (Addition of lysozyme or sodium/potassium nitrate) * Addition of CaCl2, 5-20g/100L

Answer 357

They are used in | cheese products to hinder microbial growth

Answer 358

the negative effects on cheese quality of milk contaminated by spores of Clostridium butyricum and Cl. tyrobutyricum.

Answer 359

• CaCl2 will rebalance the Ca content of milk Impact of low Ca levels • Slower coagulation of the milk • Extremely low, no coagulation at all • Softer, less stable curd Adding CaCl2 to milk • Brings the Ca content back into balance • Firmer curd - easier to cut and work with

Answer 360

• The manufacturing processes of pasteurization, homogenization, heating and rapidly cooling the milk, decreases the amount of Ca in the milk - the clotting properties are negatively affected

Answer 361

Pre-processing, inoculation, rennet, curd cutting, pre-stirring, whey draining, warming and scalding, after-stirring, forming and pressing, salting, drying and coating, maturing and sensory evaluation

Answer 362

• Addition of starter cultures 0.5 – 1%; lowers pH • Different starter cultures for different cheese types • Maturation for 5 - 60 min (short time maturation) – 8-25h (Long time maturation)

Answer 363

* 30 ml rennet/100 kg milk | * 30 °C (30 - 32 °C) i 30 min (30 - 45 min)

Answer 364

• The coagulum is broken into about 1 cm cubes with a harp • Breaking initiates whey release - syneresis from the curd • The smaller cubes, the faster syneresis à lower water content and higher DM in the cheese

Answer 365

• Careful stirring 10-15min • During this step, the starter culture continues to produce lactic acid , pH is lowered

Answer 366

30 -40% of whey is drained

Answer 367

• Usually 36-44 °C ; at approx. 38 °C the growth of starters is reduce. At 44 °C the growth is inhibited • Emmentaler, Parmasan, others; scalding at 55 °C • Heating speeds up syneresis – This treatment lasts about 15-30 minutes

Answer 368

• Stirring for 30-60 min until formation of cheese cornels | – Most of the whey is removed

Answer 369

• Gives the cheese its final shape (4-24h) • Cheddar is pressed longer under higher pressure than round- and granular eyed cheeses

Answer 370

* Salting in curd(ostmassan saltas) * Dry salting (salt på pressad ost) * Salting in brine(pressad ost i saltlake)

Answer 371

``` The curd is formed and pressed below the surface of whey to avoid the air between the individual grains ```

Answer 372

``` The curd is formed and pressed after the drainage of the whey. This will result in lot of small cavities, building a large number of small and irregular eyes ```

Answer 373

The cheese is milled and pressed | after all lactose is fermented

Answer 374

Clostridium tyrobutyricum from silage • Spores develop in anaerobic environment and produce CO2, butyric acid and hydrogen gas • The defect can create considerable loss of product

Answer 375

* Penicillium roqueforti and starters added to the cheese milk * The curd is cut in big pieces * No pressing * Dry salted * Air channels

Answer 376

``` • Penicillium camembertie or P. Candida and starters added to the cheese milk • The curd is cut in big pieces • No pressing • Salting in brine • Packed when the mould has developed ```

Answer 377

because of | the Ca loss from the micelle when acid is added

Answer 378

Low pasteurised skim milk, 32°C • Starter culture, 5-7% (0.5-1% for hard cheese) • CaCl2 + if necessary rennet 0.2ml/100kg milk (30ml/100kg for hard cheese) • Coagulation = 5h • Cutting • Paus 10 – 15 min • Stirring + heat (low from the beginning) • Warming to 55°C, 1-1.5h • Chilling, 4°C • Rinsing • Drainage (if cheese cornels are wished; Keso) • Addition of dressing (cream and salt) • Homogenization if smooth consistence is wished (Kesella) • Packaging

Answer 379

A colloidal system containing droplets of one liquid dispersed in another, the two liquids being immiscible. The droplets are the dispersed phase and the liquid the continuous phase. Must also contain an emulsifier which coats the emulsion droplets and prevents them from coalescing with each other.

Answer 380

sticky, fluid properties to the dough

Answer 381

elastic properties to the dough

Answer 382

elevates the temperature for these processes, extending the time for co2 to expand the baking dough

Answer 383

more than 10% of the dough = dehydrates yeast cells due to osmotic effect and reduces dough volume

Answer 384

heat transferred through a solid

Answer 385

heat transferred through air like steam

Answer 386

direct heat, grilling

Answer 387

bacterial toxins destroy epithelial cells, milk synthesis is lower and leakage of blood components into milk

Answer 388

lower milk production, higher protein content

Answer 389

no visible signs, reduces milk production and quality, higher cell count

Answer 390

milk production, caseins, lactose, Ca and K are lower. whey proteins, Na and Cl are higher

Answer 391

Chymosine cleaves the phe105-met106 bond of K-casein. GMP is cut off. Micelles aggregate as the result of changed hydrophilicity and loss of negative charge. Para-K-casein is left in the curd.

Answer 392

heated milk is better since denatured proteins in the heated milk help to form a more extensive protein network, resulting in cheese curds with a firmer texture

Answer 393

by lowering pH with lactic acid bacteria or acids pI is achieved, charges are neutralized and micelles aggregate. GMP is neutralized and folds in but is not cut off. syneresis is unwanted.

Answer 394

conditions for starter cultures are improved as other bacteria are eliminated. 70-80% of whey proteins, mainly beta-lactoglobulin denature and aggregate with K-casein on the micelle surface. viscosity and stability of the final product is improved. thicker texture and reduced syneresis.

Answer 395

maturation and ripening. pectinmethylesterase demethylates. polygalactorunidase degrades.

Answer 396

less mature fruits, acidity generally decreases with ripening.

Answer 397

contribute to turgor pressure and flavour

Answer 398

sugar alcohols may retain tooth mineralization. polyphenols in olive oil protects blood lipids from oxidative stress.

Answer 399

decreases Fe2+ and Ca2+ uptake

Answer 400

decreases nutrient uptake and causes blood cell agglutination

Answer 401

continue to ripen, ethylene production increases

Answer 402

``` the fatty acids composition, length, saturation, position of unsaturation, site on glycerol, stereochemistry (cis/trans). the crystal (alpha, betaprim, beta) amount, size and shape ```

Answer 403

dark spots are caused by concentration of melanin which is an antioxidant used to fight infection and heal wounds in bacteria-infested spots.

Answer 404

shortened spine and quality problems at slaughter as they are difficult to fillet. doesn't affect fish otherwise. connective tissue will be on fillet because due to muscles binding differently fish is wonky, fillet is not straight

Answer 405

myofibre detachment which causes space between cells and loss of water.

Answer 406

bruises and gear marks cause red colored muscle and blood spots

Answer 407

bacteria growing on slime in eye

Answer 408

SFC- solid fat content. SFI: solid fat index, the amount of solid fat in relation to liquid fat.

Answer 409

endosperm(coconut), cotyledons(peanut, soybean), fruit pulp(palm, olive)

Answer 410

C22:1, related to increased CVD risk

Answer 411

FA composition: large percentage MUFA and PUFA

Answer 412

the amount of free FA. extra virgin olive oil: below 0.8 %. virgin olive oil: below 1.5 %

Answer 413

the germ (oil content 30%)

Answer 414

seeds or fruit-flesh are milled or crushed. steam applied to inactivate lipases and denature proteins. oil is extracted under no, low or high pressure at low (<40) or high(65-70) temp. solvent may be used. higher temp gives higher yield.

Answer 415

degumminf, neutralization, bleaching, deodorization, winterization.

Answer 416

heat and acidic water is added. acid reacts with phosphatides (gums) and becomes insoluble in oil. separation of proteins, phospholipids from oil. phosphatides decompose, making the oil darker. Gum deposit may be formed. also removes sugars.

Answer 417

uses basic compounds to remove fatty free acids. increases stability and improves taste.

Answer 418

clay is added to oil, heated and then filtrated. clay absorbs pigments as well as residual phosphatides, metals and soap.

Answer 419

high pressure steam removes free fatty acids and other volatile compounds.

Answer 420

removes solids, saturated glycerides or waxes, that are visible at ambient or low temp. oil will not crystallize in fridge.

Answer 421

H2 added to increase saturation (reduce number of double bonds) to raise melting point and increase stability

Answer 422

oil is separated based on melting points

Answer 423

change position of FA on glycerol to be more heterogenous giving a broader SFI

Answer 424

rancidity, off-flavours and foaming

Answer 425

repulsion due to charge, steric hindrance due to size and shape, water film due to water adsorption, other compounds due to viscosity

Answer 426

melting behaviour, texture/consistency, glossiness/fat bloom, flavour release, colour, shelf life

Answer 427

palmitic acid, stearic acid and oleic acid

Answer 428

oleic acid binds to palmitic acid on one side and stearic acid on the other.

Answer 429

to achieve a correct crystallization status during processing of the product. poorly tempered fat will result in fat blooming or give too high viscosity of the product

Answer 430

first cooling: both stable and unstable crystal forms are formed. then warming up to melt unstable crystal forms. then cooling again, stable B-form crystals act as seeding agent and the whole mass will crystallize in stable form with good contraction.

Answer 431

seeds are fermented within banana leaves for 2-10 days at 40-50 degrees and then dried to 7-8% water. beans are then roasted and alkalized. shells are removed and nibs are milled and heattreated(40 C) and cooled. cocoa mass(55% butter) is divided into cocoa butter and cocoa powder (10-15% fat)

Answer 432

neutral flavour, stable against oxidation (low in PUFA), high smoke point, low amount of metal ions, appropriate SFI

Answer 433

TAG is hydrolyzed to glycerol, free fatty acids and DAG and MAG. Oxidative reactions: oxygen reacts with unsaturated fatty acids - free radical production - hydroperoxides - aldehydes and ketones. oxidative polymerization.

Answer 434

avoid water, humidity, strong acids or bases, lipase activity. short chain FA are more sensitive than long chain FA (coconut - rapeseed)

Answer 435

FA composition important, avoid: pro-oxidative metals, air, light, free FA. add antioxidants. low temp. optimal Aw. do not mix old oil with fresh oil.

Answer 436

Ascorbic acid is usually reducing but is converted by an enzyme to dehydroascorbic acid which is oxidizing. It can then help to strengthen gluten by increasing the number of cystins. In addition, dehydroascorbic acid in an enzymatic oxidative reaction contributes to glutathione forming a dimer of glutathione. Glutathione is an antioxidant present in the flour that can react with the sulfur group on cysteine and thus prevent disulfide bonds between glutenins. In dimer form, it cannot react with cysteine on glutenins and prevent the formation of disulfide bonds. Ascorbic acid can therefore provide stronger gluten with more disulfide bonds between glutenins.

Answer 437

Cysteine is important for the formation of disulfide bonds between glutenins forming the large protein complexes in gluten. Glutamine contributes with formation of hydrogen bonds which also contributes with interactions (although not as strong as the disulfide bonds) between the proteins in gluten (gliadins and glutenins). Large numbers of proline (as is the case in gluten) prevents the formation of ordered structures such as alpha-helices and beta-sheets. Instead it induces kinks and bends in the protein structure which can contribute to the elastic properties of gluten.

Answer 438

9 % shell, 63,8 % albumen (egg white), 27,2 % yolk.

Answer 439

Ovalbumin, conalbumin (binds metal ions), ovomucoid, lyzoenzym

Answer 440

heating, dilution, sugar, salts, pH

Answer 441

surface active substances in yolk, lipoprotein and phospholipids

Answer 442

since most of the allergic reactions to egg is against proteins in the albumen, egg yolk powder is suitable for infant formulas and pharmaceutical applications like intra lipid.

Answer 443

1. give antigen to hen. 2. egg yolk will contain antibodies. 3. antibodies will be purified from egg yolk.

Answer 444

shelf life, easy to handle, transport and storage are easy compared to fresh eggs, development potential

Answer 445

diffusion of CO2

Answer 446

-fatty acid composition - colour of egg yolk - antioxidant content of egg yolk

Answer 447

feeding hen flaxseed, rapeseed or fish oil

Answer 448

eggs naturally have a wax coating which prevents m.o. entry, this wax layer can be removed by cleaning

Answer 449

it has a high flouride content

Answer 450

squid, octopus,mussles, escargot

Answer 451

only the muscle

Answer 452

high yield, 70-80%

Answer 453

shrimp, crap, langusts

Answer 454

dying algae after algae bloom produce toxins not to be eaten, however molluscs are not affected by this toxin and eat the algae anyway. however, toxins can be dangerous for humans.

Answer 455

diarrhetic and paralytic(potentially deadly)

Answer 456

as UV protection for eggs or molluscs that are shifting shells

Answer 457

cephalopods, bivalves, univalves

Answer 458

denaturation of proteins surrounding astaxanthin reveal the antioxidant

Answer 459

Limited fermentation, reverse osmosis, vacuum distillation

Answer 460

Good protein profile with content of essential a.a. and high total protein. Chitin acts as dietary fibers in our gut. A large percentage of the animal is edible.

Answer 461

A spice is a seed, fruit, root, bark, or other plant substance primarily used for flavoring, coloring or preserving food. Spices are distinguished from herbs, which are the leaves, flowers, or stems of plants used for flavoring or as a garnish.

Answer 462

It can lower blood pressure. Soy beans contain high levels of phytic acid which causes a reduced absorption of minerals.

Answer 463

Plant proteins are generally incomplete proteins. Their availability increases with cooking.

Answer 464

Lactic acid bacteria cause lowering of pH which inhibits m.o., as well as the sausages having a relatively low water activity.

Answer 465

High fat and protein content gives a higher curd yield.

Answer 466

akoha s1 casei, thought to be the main protein in cow milk to cause allergies is present in low amounts in goat milk. also, fat globules are smaller and easier to digest.

Food technology Flashcards

(496 cards)