Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Now there is a way to tell the difference between battery laid eggs and free-range or barn

11.04.2005


Scientists have developed a method of determining whether eggs labelled as ‘free-range’ or ‘barn’ have in fact been laid under battery conditions. The procedure, published in Journal of the Science of Food & Agriculture this month, means eggs can be tested without the need to visit farms.



The give-away is the dust that the eggs pick up from the surface on which they are laid.

Because the eggs are wet when freshly-laid, the dust attaches to the shell surfaces. The pattern this creates varies according to whether the eggs were laid on cage floors, barn nestboxes or outside. These distinctive patterns can easily be distinguished under ultraviolet light, as the dust fluoresces.


Professor Neville Gregory of the Royal Veterinary College, UK and colleagues in Australia used ultraviolet light to examine the surface patterns on 11520 eggs from cage, barn and free-range production systems.

360 eggs from each of 20 cage, seven barn and five free range units were examined, and categorised according to their dust patterns when exposed to UV light. The type of floor material onto which each egg was laid was known for each farm.

The authors found that the prevalence of white double parallel lines with 2-2.5cm spacing was a distinguishing feature for eggs laid on wire floors in cages.

They conclude that if five or more eggs in a sample of 90 eggs have double fluorescent lines that there is a greater than 999 in 1000 probability that the batch contains some cage-laid eggs.

“The method is effective in distinguishing between free-range eggs and those laid on a wire floor cage,” said Professor Gregory.

“It does not damage the eggs, and can be applied at any stage in the egg marketing chain.”

However, washing the eggs removed or obscured the double lines, so the authors recommend that in countries where egg washing is common, it is best to perform the test before washing.

Distinguishing features in egg shell fluorescence can be used to identify when eggs have been washed, and they can also be used in preliminary screening tests for sun exposure, which in some countries is a cause of runniness of the egg white.

Virginia Fisher | alfa
Further information:
http://www.rvc.ac.uk

More articles from Agricultural and Forestry Science:

nachricht Cereals use chemical defenses in a multifunctional manner against different herbivores
06.12.2018 | Max-Planck-Institut für chemische Ökologie

nachricht Can rice filter water from ag fields?
05.12.2018 | American Society of Agronomy

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Magic number colloidal clusters

13.12.2018 | Life Sciences

UNLV study unlocks clues to how planets form

13.12.2018 | Physics and Astronomy

Live from the ocean research vessel Atlantis

13.12.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>