The Great Big Egg-tasting Test

In a recent blog post by Lorenzo the Llama about Chickens and Eggs, the various differences between free range, organic and caged eggs were discussed. In some of the ensuing comments it was asserted that there is a taste difference between these sources. Now, the choice of whether to buy eggs from free range hens or eggs from caged hens is essentially a moral one and remains a personal judgement. However, on the matter of taste we are able to make a scientific exploration of the phenomenon by devising a taste-trial experiment.

In this case, three eggs of known origin were cooked and supplied "blind" (i.e. she did not know which egg was which before tasting) to Lorenzo for breakfast this morning. It was pointed out that a negative result (that is, failure to correctly identify any of the eggs) would really defy any notion that taste is a useful basis for selection.

On the other hand, with a sample of only three eggs in a single trial, correct assignment could be expected in about 1 in 6 trials simply by guessing. You would need to reduce this to about 1 in 20 before the result could be regarded as "significant" and so more trials would be necessary. For example, you would not market a drug that had a 1 in 6 chance of killing you.

However, a first time correct assignment would be an extremely suggestive result that would undoubtedly justify the award of a research grant for further study.

Lorenzo was offered a choice of cooking method, and accepted my suggestion that boiling would eliminate another variable in so much as all three eggs could be put into the water at exactly the same time and boiled for exactly the same duration.

Lorenzo the Llama ponders her choice

She was told that the three eggs represented: (a) "Farm Fresh" free range egg; (b) "barn egg", i.e. from hens that had been allowed to move about in the barn; (c) egg from a caged "battery" hen.

I did NOT tell her that the "caged" egg was in fact over a week older than its "sell by" date, and nearly two weeks older than its "display date. Lorenzo said she would make her choice on the basis of taste and colour preference.

Using clues from yolk colour - that was no yolk!

Here are the results.

Egg A: Actual: Barn egg.
Lorenzo's judgement: Her second choice

Egg B: Actual: Caged egg.
Lorenzo's judgement: Her FIRST choice

Egg C: Free range egg.
Lorenzo's judgement: Her THIRD choice

Whilst this simple test cannot be said to "prove" anything, there is clearly no evidence whatsoever emerging from this trial to suggest that free-range eggs taste any "better" than caged eggs. Indeed, it is fascinating that her favourite was the "mature" caged egg. But then taste is a matter of personal value judgement.

Maybe the Chinese have something after all by letting their eggs mature ofr 100 years.

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Maalie in Lapland

Maalie is about to depart for Lapland. His aim is to be north of the Arcticle Circle about the time of the Autumn Equinox in order that appropriate seasonal rituals may be undertaken. He looks forward to seeing you again in mid-September.

Normandy Ringing Camp

On the north shore of the estuary of the River Seine in Normandy, just east of Le Havre, is a vast reed bed (Phragmites australis) of some 8500 hectares, bisected by the new Pont de Normandie. The area is a nature reserve, the Réserve Naturelle Nationale Estuaire de la Seine, and is enormously important as a stopover for birds migrating from central and eastern Europe on their way south to their wintering grounds in Africa. The reeds support a vast biomass of invertebrate life upon which the birds feed to fatten up in order to store enough "fuel" for their flight across the Sahara.

Among the many bird species which depend on this area during migration is our most globally threatened migratory song-bird, the Aquatic Warbler, that has a restricted breeding range in Poland, Belarus and the Ukraine.

Ringing friend Ken and I were invited by a team of French ornithologists to join a bird-ringing camp (August 4-12) in Normandy to assist in catching and ringing migratory birds in order to study their biology and migration.

The grandeur of our residence near Harfleur, the gite, somewhat belies the description of "ringing camp"

The modern Pont de Normandie bisects a vast reed bed of some 8500 hectares

You can see the line of mist net poles tracing out the 'ride' cut through the reed bed

Extracting birds caught in the mist nets

Ken and I were responsible for ringing and processing some 1200 birds of 15 species during our week at the camp, including over 500 Sedge Warblers, 350 Reed Warblers, 40 Marsh Warblers, 40 Savi's Warblers, 30 Bearded Tits, 20 Bluethroats and 20 Cetti's Warblers. Of course we were both able to see and handle several species for the first time.

It was not until the third day that we actually caught the bird-ringer's 'Holy Grail' of warbler species, namely the Aquatic Warbler, and the week provided a total of five for our team.

Bruno and Ken compare the similar Reed and Marsh Warblers

A colourful male Bluethroat, a close relative of the Robin

The Bearded Tit is known in French (perhaps more appropriately) as the "Moustached Tit"

The stripy, if rather drab, Aquatic Warbler, was the main target species of the research

The nearby port of Honfleur provided an opportunity for a glass of Calvados and a croque Monsieur

We both felt that participation in this international research project was immensely rewarding and gave us opportunities to exchange information, ideas and techniques. We recorded 84 bird species during the week (including those caught and ringed) the most notable of those seen but not ringed being Spoonbill, Fan-tailed Warbler, Little Gull, Green and Wood Sandpipers, Honey Buzzard and (on the ferry crossing) Storm Petrel and Great Skua.