Cause

Control

Old eggs

Avoid the development of ‘stale odours’ by minimising storage time. High temperatures accelerate the development of ‘stale odours’. Reduce temperatures in the layer shed in summer. Collect eggs at least twice daily and even more frequently in summer.

High storage temperatures

Store eggs in a coolroom as soon as possible after collection, preferably at a temperature of 12 to 15 °C. Oil eggs soon after collection. Use only an oil such as Caltex Pharma White 15 BP/USP, approved for this purpose by the relevant authorities.

Poor storage conditions

Absorption of foreign odours from the storage environment can produce off odours and tastes in the egg. Among materials implicated are:
• fish oils and meals.
• sour milk.
• strongly scented or decaying fruit and vegetables.
• mould.
• disinfectants.
• kerosene.
• poultry droppings.
Eggs that have been oiled are less likely to absorb foreign odours.

Strongly fl avoured feed ingredients

‘Fishy’ or other undesirable flavours may be produced by feeding:
• excessive amounts of low-grade fish meals or fish oils.
• some vegetables including onions, turnips and excessive amounts of cabbage.
• rapeseed.

Micro-organisms

Certain bacteria and fungi growing either on the outside or the inside of the egg may give an undesirable odour or fl avour to the egg contents without causing noticeable spoilage. Use the same control measures as to minimise the incidence of rotten eggs (see page 57), e.g. avoid faecal contamination, use proper washing procedures, store eggs correctly and make sure they are as fresh as possible.

Persistent layers of off-flavoured eggs

Individual birds can continue to produce off-flavoured eggs regardless of feed and egg storage conditions. Such birds should be culled, but tracing them is extremely difficult.