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Author Topic: milk and temperature  (Read 3371 times)

paul.fr

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milk and temperature
« on: 01/05/2007 17:39:47 »
i was going to entitle this "poor cow", but thought i better not.

OK, i was just pouring some milk it to my coffee, and i wondered. At what temperature is milk stored in the cow? and if not drunk by the little cow, does it go off?


 

Offline neilep

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milk and temperature
« Reply #1 on: 01/05/2007 23:39:38 »
I think ewe could have called the thread  ' Poor Cow ' and then followed on with ' milk and temperature '



We need a vet !.....it just so happens that we're making two rings for a couple of vets..I don;t think they'll appreciate my calling them now though !!

Great question Paul !..............I suspect the modern cow.....doesn't get a chance to retain all it's milk long enough ...and you rarely find wild cows !!..and if you do..I suspect that they would not produce any way near as much milk as todays dairy cow ...

I wonder if your question can be relayed to Moose ?..seals ?....whales ?...wild pigs ? etc etc
 

paul.fr

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milk and temperature
« Reply #2 on: 01/05/2007 23:43:23 »
ermmm, i asked because i always smell the milk to see if it's ok before drinking. obviously we keep it refrigerated to stop it going off, but how do cows, and like you say other milk producers stop theirs going off?
 

Offline neilep

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« Reply #3 on: 01/05/2007 23:47:24 »
Well, I'm clearly not the expert here but cow's milk probably retains it's freshness cos it's still inside the cow !...and hasn't been subjected to due process of dairy farming and then allowed contact with air....with all it's bad germs and stuff !
 

Offline Carol-A

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milk and temperature
« Reply #4 on: 02/05/2007 12:06:00 »
It is just the same as in people! The milk in the cow is sterile, and doesn't go off. If it is not used, it is gradually re-absorbed into the body. The cow produces milk according to demand, so if you don't take it, the cow will stop making it. It would be quite painful for the cow.... an abrupt stop.... and could cause serious problems.
 

Offline chris

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milk and temperature
« Reply #5 on: 02/05/2007 12:47:23 »
Carol is quite correct - when the milk is inside the cow is is sterile. Bugs gain access to milk as it leaves through the nipple (udder teat) and from contact with contaminated equipment and receptacles.

If you study breast / udder tissue under a microscope you see a branching system of ducts rather like a tree or river system. Where these unite is the main duct leading to the nipple.

These ducts are lined by epithelial cells which are specialised to secrete milk. They extract water from blood and pump it, together with proteins (casein), into the ducts, which progressively fill up with milk. When a baby suckles, or a farmer connects a milking machine, smooth muscle cells around the ducts squeeze under the influence of a hormone called oxytocin, expressing the milk. A breastfeeding mother will often notice milk dripping from the opposite breast as a baby feeds, due to this effect.

The secreted material is also continuously re-scavenged by the duct cells, but at a much slower rate than it is produced. This keeps the milk composition fresh and also means that if the milk is not used it is slowly reabsorbed and disappears. Production is also matched to demand, so the more you use the more you produce and vice versa.

Interestingly, the same is also true of the testes. Men who have had vasectomies are often worried that they will accumulate gallons of sperm that can't escape and ends up going mouldy. Not the case. Just like the breast milk, sperm is continuously produced and reabsorbed. So men (and women) can sleep easy...!

Chris
 

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milk and temperature
« Reply #5 on: 02/05/2007 12:47:23 »

 

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