Meat, Fish, Eggs, Alternative Proteins

Question 1

organic egg

Answer 1

from birds that are fed special organic feed that is not treated with chemical pesticides or fertilisers.
the birds are also not treated with growth hormones or given antibiotics

Question 2

lecithin egg

Answer 2

found in egg yolk
natural emulsifier (explain emulsification underlying principle)

Question 3

cold smoking fish

Answer 3

involves subjecting a fish to smoke from wood chips
the chemicals creosote and formaldehyde in the smoke prevent microorganism growth on the fish flesh
temp doesnt go beyond 27 degrees so fish must be cooked further

Question 4

hot smoking fish

Answer 4

same as cold but temp is gradually increased to approx 80 degrees
doesnt require further cooking

Question 5

effects of cooking on proteins in meat

Answer 5

proteins coagulate causing the fibres to shrink at 40-50 degrees
collagen converts to gelatine, making meat more digestible as the fibres loosen and fall apart

Question 6

nutritive value of fish

Answer 6

HBV protein - myosin, actin
oily fish - polyunsaturated fat, omega 3s eg EPA and DHA
no fat in white fish
lack carbs - any glycogen is converted to lactic acid when caught
b group vitamins B6 and B12
oily and white fish Vit A and D
minerals - small amount iodine, zinc, phosphorous
shellfish iron
canned fish calcium as bones are eaten
water content varies on type (higher the fat, lower the water)

Question 7

main causes of fish spoilage

Answer 7

oxidative rancidity
enzymes
bacteria

Question 8

oxidative rancidity fish spoilage

Answer 8

oils in oily fish react with oxygen in the air

oxygen combines with the carbons in the double bond of the unsaturated fatty acid chain, causing the fish to turn rancid

Question 9

enzymes fish spoilage

Answer 9

naturally present enzymes in fish cause its flesh to deteriorate, even at low temperatures.
can be slowed by placing on ice or in fridge

Question 10

bacteria fish spoilage

Answer 10

when fish are caught they struggle frantically, using up the glycogen in their muscles and liver
this results in little glycogen being left to convert to lactid acid to preserve the fish, which in turn causes rapid deterioration by bacterial action
produces a strong smelling nitrogen compound, trimethylamine

Question 11

nutritional significance of eggs

Answer 11

HBV protein - ovalbumin and globulin
fat - saturated in yolk. dispersed as a fine emulsion due to the presence of lecithin 
yolk contains cholesterol
carbs- lacking
vitamins- B1, B2, B3 , B12
yolk has vit A,D,E,K
minerals- calcium, phosphorous, zinc, sulphur, non haem iron
water- high content

Question 12

properties of eggs

Answer 12

aeration
coagulation
emulsification

Question 13

aeration eggs

Answer 13

when eggs are whisked, protein chains unfold and air bubbles form

protein chains entrap air, creating a foam
whisking eggs also creates an amount of heat that begins to set the egg albumin, creating a temporary foam
it will collapse unless heated to coagulate and set as a permanent foam
culinary use: meringue, souffle

Question 14

coagulation eggs

Answer 14

when eggs are heated, protein chains unfold, straighten and bond together around small pockets of water
egg whites- 60 degrees
yolk-68 degrees
culinary use: cooking eg fried egg, thickening eg custard

Question 15

emulsification eggs

Answer 15

lecithin in egg yolk is a natural emulsifier
has the ability to join two immiscible liquids
underlying principle of emulsification
culinary use: mayonnaise, hollandaise sauce

Question 16

nutritional significance of meat

Answer 16

HBV protein- myosin, collagen, actin
fat - saturated
visible or invisible
depends on type eg pork has more than beef
carbs- lacking
vitamins- B1, B2,B3, B6,B12
minerals- iron, zinc, sulphur, phosphorous
water- depends 
higher the fat, less water

Question 17

factors causing toughness in meat

Answer 17

age- older have more connective tissue, connective tissue is stronger, muscle fibres are longer and thicker
activity- meat from active parts of the animal eg leg is tougher, as it develops longer muscle fibres and more connective tissue

Question 18

methods of tenderising meat

Answer 18

mechanical breakdown- eg pounding with meat hammer breaks down fibres into smaller shorter length, tenderising meat
marinating- in a mix of acid, salt, herbs, spices, fruit or dairy breaks down fibres, tenderising meat
meat tenderisers eg papain - break down fibres

Question 19

process to extend shelf life of meat

Answer 19

freezing
meat is deboned and some fat is removed. it can then be frozen by commercial methods eg blast at -30 or home freezing at -25
no effects on colour, taste, texture
microorganisms deactivated
some loss of b group vit due to drip loss when thawed
freezer burn may occur if packaging is damaged

Question 20

methods of quality assurance in egg production

Answer 20

all feed is heat treated for hens
eggs carry best before date, house code and logo
incoming hens must be certified as salmonella free

Question 21

dry method of cooking fish

Answer 21

baking
cooks by convection currents
fan oven evenly distributes heat
steam produced by the food prevents drying out
enhances flavour
crisp finish eg breaded fish

Question 22

moist method of cooking fish

Answer 22

steaming
cooks by steam rising from boiling water
food doesn't touch the water
steam circulates around the fish
digestible but can lack flavour