red Posted April 27, 2007 Share Posted April 27, 2007 This is one of the rather interesting experiments being carried out by the Daily Telegraph - click here to see how quickly, if at all, egg white goes mouldy .... (mind you it's only Day 1 ) Quote Link to comment Share on other sites More sharing options...
Lesley Posted April 28, 2007 Share Posted April 28, 2007 I thought at first it was the scotch egg - but then realised that that is one of the control foods. It will be interesting to see if he's right. Quote Link to comment Share on other sites More sharing options...
Egluntyne Posted April 28, 2007 Share Posted April 28, 2007 It'll be a bit like watching paint dry! Quote Link to comment Share on other sites More sharing options...
Sheilaz Posted April 28, 2007 Share Posted April 28, 2007 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 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? Quote Link to comment Share on other sites More sharing options...
chocchick Posted April 28, 2007 Share Posted April 28, 2007 See http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2007/04/28/nscience28.xml&page=2 It's a do at home experiment to encourage kids into science Quote Link to comment Share on other sites More sharing options...
Sheilaz Posted April 28, 2007 Share Posted April 28, 2007 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. But, I'm all for children trying out experiments & learning more in a fun way. Quote Link to comment Share on other sites More sharing options...
chocchick Posted April 28, 2007 Share Posted April 28, 2007 It's going to bother me not knowing about egg yolks now Quote Link to comment Share on other sites More sharing options...
Lesley Posted April 28, 2007 Share Posted April 28, 2007 Just conduct your own experiment CC - put a whole egg on a plate - and watch it Do let us know how you get on......... Quote Link to comment Share on other sites More sharing options...
Louise Posted April 30, 2007 Share Posted April 30, 2007 The yolk is where the protein is so I suspect that is what turns an egg rotten and produces the foul stink Quote Link to comment Share on other sites More sharing options...
Lesley Posted April 30, 2007 Share Posted April 30, 2007 so why are they just testing with egg white and saying that this is why we don't need to keep eggs in the fridge? I don't keep mine in the fridge anyway - but the experiment doesn't seem to make sense Quote Link to comment Share on other sites More sharing options...
JohnP Posted April 30, 2007 Share Posted April 30, 2007 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! Quote Link to comment Share on other sites More sharing options...
chocchick Posted April 30, 2007 Share Posted April 30, 2007 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 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? Quote Link to comment Share on other sites More sharing options...
JohnP Posted April 30, 2007 Share Posted April 30, 2007 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! Quote Link to comment Share on other sites More sharing options...
The Dogmother Posted April 30, 2007 Share Posted April 30, 2007 hmmmm, lovely Quote Link to comment Share on other sites More sharing options...
red Posted April 30, 2007 Author Share Posted April 30, 2007 What a high brow thread I've started here! JohnP - sounds like you could write a thesis on egg white! Quote Link to comment Share on other sites More sharing options...
Lesley Posted May 1, 2007 Share Posted May 1, 2007 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.? Quote Link to comment Share on other sites More sharing options...
Sheilaz Posted May 1, 2007 Share Posted May 1, 2007 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. Quote Link to comment Share on other sites More sharing options...
JohnP Posted May 1, 2007 Share Posted May 1, 2007 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! ) Quote Link to comment Share on other sites More sharing options...
Lesley Posted May 1, 2007 Share Posted May 1, 2007 Yes, the experiment is more or less irrelevant to the question of whole eggs. Thank you.... thank you! I feel much better now........ Quote Link to comment Share on other sites More sharing options...
