Eggs Flashcards
Types of eggs
Free range eggs - roam free, outside for part of day
Barn eggs- roam free large barns
Cage eggs - slanted floors
Organic eggs - fed organic feed, no chemicals or pesticides, no growth hormones or antibiotics
Omega 3 eggs - fed high omega 3 diet
Nutritional % eggs
Fat 12%
Protein 12%
Carbohydrate 0%
Water 74%
Proteins in egg white
Ovalbumin
Globulin
Protein in egg yolk
Vitelin
Livetin
Type of fat in yolk
Saturated
Vitamins in eggs
Fat solubles A D E K
Beta carotene (a)
Water soluble B1, B2, B3, B12
Lack vitamin C
What gives yolk it yellow colour
Beta Carotene (a) vitamin
Minerals in eggs
Iron, phosphorous, sulphur, zinc, selenium, calcium
Parts of egg
Shell Yolk Membrane Air space Chalazae White Yolk
Describe the shell
Made of calcium carbonate for protection.
Porous (water, gases, odours)
Membrane inside holds egg in place
Water evaporates out of white through shell, air space becomes
larger, eggs become lighter and are gone off
10%
Describe the white
Viscous colourless fluid
Thin and watery when stale
60%
Describe the yolk
Held in place by chalazae
Very nutritious
30%
Eggs contribution to diet/ benefits of eggs
Easy to Digest - kids, elderly Protein Meat alternative Economical Cook quickly Versatile Saturated fat - Hugh cholesterol Not vitamin c Served with carbohydrates as lack
Culinary uses of eggs
Binding Emulsifying Aerating Thickening Garnish Coating Whole Glazing Enriching
Effects of cooking on eggs
Protein coagulates
Pathogenic Bacteria is destroyed
Egg white turns from clear to opaque
Curdling if temperature too high
B group vitamin lost - not heat sustainable
Green ring of sulphide around yolk if over cooked
Over cooking = crumbly yolk, rubbery white and hard to digest
Guidelines for buying eggs
Check date Heavy No cracks or breaks Carton information Free range to be more consumer aware
Egg must be labelled with
Best before date
Code letter for county and farm of production
Way chickens were kept number
Egg box must have
Name address and information of packer Quality of eggs (a, b) Size Best before date Sprague instructions Number of eggs in pack
Storage of eggs guide
Fridge to keep fresher for longer
Pointed end down to precent chalazae from breaking and egg yolk being intact
Away from strong smelling foods - porous
Used at room temperature
What happens when eggs are whisked (aeration of eggs)
Protein chains unfold and bubbles form
Protein chains trap air and create foam
Heat sets egg albumin ( heat occurs when whisking )
Foam will collapse if egg isn’t heated to coagulate permanently eg in meringue
What happens when eggs are heated ( explain coagulation of eggs)
Eggs are heated
Protein chains unfold and clump together around pockets of water causing coagulation
Egg white colour change
Over cooking causes proteins to clump together and squeeze out water leaving lumps of protein and watery liquid (curdling)
Eg in frying eggs
Describe how emulsification happens
Lectin is a natural emulsifier in egg yolk
It can join two immiscible liquids eg oil and water due to its HYDROPHILIC head ( water loving) and HYDROPHOBIC tail (water hating) .
Water attached to head, oil attached to tail preventing them from separating.
Eg mayonnaise
To get bord bia quality mark eggs must:
Be routined salmonella checked
Have accurate records of origin, age , sex , breed, movement and veterinary records of eggs
Feed given to hen mustn’t be contaminated by bacteria
Thorough Sanitation in packing plant
Staff have HACCP and food safety training
What does HACCP stand for
HAZARD ANALYSIS AND CRITICAL CONTROL POINT
