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Sir Tim Hunt's Rotten Egg Cam

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:? But, if you leave a whole egg long enough it will go very, very rotten, not just dried up!

Maybe it's the yolk that goes bad, but I don't quite see the purpose of his experiment.


This week I found a clutch of eggs in a hidden nest in the garden :roll::twisted:

They'd obviously been there a long time, I wasn't going to eat them. But, when I picked them up to dispose of, a shell or 2 broke. It was the worst smell, and lingered too. I'd forgotten quite what a stench a rotten egg makes, you really don't want to know!


So, what's he doing with albumen in a jug. Nothing to do with storing whole eggs is it? :?

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8) Well, that's good, and it is interesting, thanks Choccy.

But, the page I'd read said "so there's no need to store them in the fridge". Which, there isn't, but it's a red herring as the experiment isn't the whole egg. :roll:


But, I'm all for children trying out experiments & learning more in a fun way. :)

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It's slightly more complicated than that.


Egg white is almost pure protein, but the crucial point is that quite a chunk of that protein is an enzyme called lysozyme. This protein kills bacteria, and so protects the embryo within from bacteria that manage to make it through the outer membrane.


Egg yolk contains protein, fat, vitamins and lots of other good stuff - everything needed for a chicken embryo to grow into a chick. This is ideal substrate for bacteria (or anything else) to grow on. So, if it's left exposed, yolk will very quickly go putrid (the characteristic "bad egg" smell is hydrogen sulfide and is the result of sulfur-containing compounds like protein being digested by bacteria).


Hope that makes things a little clearer!

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My link I put in above says:

Egg white contains ovotransferrin, avidin and lysozyme, antibiotics which stop it going mouldy.


See I can't rest not knowing about the yolk :roll:


What are the proteins in the white/yolk apart from albumin in white?


What happens to an egg stored for too long before eating if unbroken? Do the bacteria overwhelm the antibiotics as they multiply, or do the antibiotics denature? Does storing at 4 degrees slow down the proteins denaturing maybe?

Gas builds up doesn't it-is this produced by the bacteria?

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Albumin makes up most of the protein in the white. Actually "albumin" is something of a catch-all term for a family of proteins, and together they make up well over 90% of the protein content of the white! Lysozyme is 3.5% of the protein content and is therefore the predominant protective protein.


If an egg is unbroken, it will sit for ages until one of two things happens. First, a bug of some sort will eventually get in and survive and start growing. (All proteins have limited lives, and so the protective effects drop over long periods of time. After all, the egg is designed to last only as long as a chick takes to hatch! Keeping it in the fridge will slow down the deterioration, but increases the chances of bacteria getting throug the outer membrane.) Failing infection, the fat in the yolk will eventually go rancid by itself - all biological molecules are more or less unstable. Gas production is (I believe) most likely to be the result of microbial infection of the egg - the breakdown of fats (rancidification) doesn't produce gas, if I remember correctly.


Such an attractive discussion! :-)

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Thanks for the info John - but please tell me why they are only using egg white to prove that whole eggs don't need to go in the fridge.


If it's because the white is protecting the yolk and the white has properties which ensure that it doesn't go mouldy then why don't they say so in their info.?

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Thanks for the info John - but please tell me why they are only using egg white to prove that whole eggs don't need to go in the fridge......quote]


That was my original point, Lelsey...eggs do go rotten & they absolutely stink, worse than almost anything.

So, I think it is taking a common fact...eggs go rotten...and then, er, having a bit of fun with some egg white for no particular reason, except it's fun to do experiments . So, I've accepted that but find it an odd thing to do.


It would have been more fun to encourage children to make stink bombs. Oh, perhaps not. :oops::lol:

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Yes, the experiment is more or less irrelevant to the question of whole eggs. However, it does show how wonderful egg white is. Generally, you can leave it out until it has completely dried up, and it still won't grow anything. So, it does show that eggs won't generally start rotting any faster if left out of the fridge. Perhaps the rate at which you find rotten eggs doubles, but it's so low in the first place that it's not a hugely significant increase. And, given that storing eggs in the fridge can increase the rate at which bacteria penetrate the membrane, that's generally reckoned to cancel out any benefit of the lower temperature.


Which is all a long-winded way of saying why the advice about storing eggs flip-flops between fridge and cupboard - there's really not much in it!


(You might have spotted, I'm a biologist by education and inclination. Wikipedia's great for reminding one of the details, though, provided you know enough already to discount the dross! :-) )

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