Eggs

VRQ2 Theory Unit 712 UPK 712

Eggs as a Food source

    Eggs are an ancient source of food They are self contained incubators for growth Everything required for the complete growth of a animal that hatches from an egg is enclosed within Therefore it is a complete source of nutrition for others

How an egg is formed

    Process Takes approx 25 hours Yolk forms around Germ cell (hen chromosomes) mainly fat and proteins Detaches from ovary and begins journey down the oviduct 4 layers of egg white, 1 antimicrobial membrane, shell.

Structure

Structure

Stage 1

Stage 2

Stage 3

Stage 4

Stage 5/6

Nutrition of Eggs

     High in protein High in Fat High cholesterol levels Low in Sodium Low in carbohydrates

As Eggs get Older As an Egg gets older changes take place that are visible and that will effect the quality of the dishes being produces.

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Those changes are:

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Air sac increases in size due to evaporation of water vapour through the pores in the shell.

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Water is transferred to the yolk from the white so the yolk membrane weakens causing the yolk to flatten.

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Yolk becomes displaced and settles against the shell instead of being firmly suspended in the white, due to weakening of chalazae strands.

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Thicker white weakens and becomes watery.

Quality Points

      Clean Shell Undamaged Shell Within use by date Quality marks Origin and type Correct size

Egg Quality

Under European law there are two classes of egg quality: A & B.

Grade A : eggs are the highest grade. They are naturally clean, fresh eggs, internally perfect with shells intact and the air sac not exceeding 6mm in depth. The yolk must not move away from the centre of the egg on rotation. Grade A eggs are sold as shell eggs. Grade B: eggs are broken out and pasteurised. In addition, there is another class of eggs called industrial eggs which are for non-food use only and are used in products such as shampoo and soap.

The Lion Quality mark

The Lion Quality mark on egg shells and egg boxes means that the eggs have been produced to the highest standards of food safety.

The Lion Quality Code of Practice was launched in 1998 and includes compulsory vaccination against Salmonella Enteritidis of all pullets destined for Lion egg-producing flocks, independent auditing, improved traceability of eggs and a "best-before" date stamped on the shell and pack, as well as on farm and packing station hygiene controls.

Battery Hens

(laying cage system)

50% of Total Egg Production In the UK Typically a laying cage system consists of a series of at least three tiers of cages. The cages have sloping mesh floors so that the eggs roll forward out of the reach of the birds to await collection. Since 2003 new enriched cages where installed with 750cm² per bird along with a nest, perching space and a scratching area. Before this conventional cages required a minimum of 550cm² per bird. Food is supplied in troughs fitted to the cage fronts and an automatic water supply is provided. The units are kept at an even temperature and are well ventilated. Electric lighting provides an optimum day length throughout the year.

Free Range

45% of Total Egg Production In the UK The Welfare of Laying Hens Directive stipulate that for eggs to be termed 'free range', hens must have continuous daytime access to runs which are mainly covered with vegetation and with a maximum stocking density of 2,500 birds per hectare.

Barn System’s

5% of Total Egg Production In the UK In the barn system the hen house has a series of perches and feeders at different levels. The Welfare of Laying Hens stipulate a maximum stocking density of 9 hens per square metre of useable floor space. Water and feeding troughs are raised so that the specially prepared food is not scattered. Electric lighting is provided to give an optimum day length throughout the year. At the end of the laying period the house is completely cleared and disinfected.

ORGANIC EGGS

Eggs from hens fed rations having ingredients that were grown without pesticides, fungicides, herbicides or commercial fertilizers. No commercial laying hen rations ever contain hormones. Due to higher production costs and lower volume per farm, organic eggs are more expensive than eggs from hens fed conventional feed. The nutrient content of eggs is not affected by whether or not the ration is organic “Hens producing organic eggs are always free range. In addition, hens must be fed an organically produced diet and ranged on organic land.”

Hygiene Issues

   If sourced from a farm, could be a host for Salmonella Should be stored in the fridge in airtight box to prevent the absorption of strong odours Safest type is pasteurised egg      Advantages; Salmonella free Longer shelf life Ease of use (tetra packed) Safe for uncooked dishes (mousses, mayonnaises)

Egg Facts

UK production Imports Total UK consumption Retail market 791 million dozen eggs 18 million dozen eggs No of UK laying birds 660 million eggs £582m 32.9 million Average yield per bird pa 311

Duck, Gulls, Goose and Plover

Other Eggs

Quail

Ostrich

Cooking Eggs

There are many recipes for cooking eggs all of them fall into one of the following basic cooking methods : Boiling Poaching Fried Scrambled Omelette En Cocotte Sur le Plat

Classical Egg Garnishes

      These are dependant upon the named dish, but there is a theme to the garnishes.

Scrambled Eggs; fried bread En cocotte, sauce of appropriate type in a thin thread around Hard Boiled, roux based white sauce Poached or soft boiled, dependant upon the name, but usually nape with the sauce and decorated with the appropriate garnish Omelettes, Sur le Plat; dependant upon name

Questions ????