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Old 23-October-2009, 03:46 PM
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Smile Whatever happened the creamy layer at the top of bottles of milk?

When I was young, growing up in the inclement weather of Yorkshire, milk was delivered to our house early each morning by a milkman. The milk came in glass bottles sealed with foil caps. My mum liked us to drink full cream milk. The cream used to rise and settle at the top of the bottles, creating a layer about an inch deep, which was frequently eaten by birds that pecked through the foil caps, or fought over by me and my sister to put on our breakfast cereal (yum).

Nowadays I buy my full cream milk at the supermarket, in a carton. It doesn't matter how long I leave the carton standing - the cream never rises to the top in a yummy layer. What has happened to modern milk to make the yummy creamy layer disappear?

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Old 23-October-2009, 03:51 PM
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Homogenization (link from University of Guelph Dairy Science)
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Milk is an oil-in-water emulsion, with the fat globules dispersed in a continuous skimmilk phase. If raw milk were left to stand, however, the fat would rise and form a cream layer. Homogenization is a mechanical treatment of the fat globules in milk brought about by passing milk under high pressure through a tiny orifice, which results in a decrease in the average diameter and an increase in number and surface area, of the fat globules. The net result, from a practical view, is a much reduced tendency for creaming of fat globules. Three factors contribute to this enhanced stability of homogenized milk: a decrease in the mean diameter of the fat globules (a factor in Stokes Law), a decrease in the size distribution of the fat globules (causing the speed of rise to be similar for the majority of globules such that they don't tend to cluster during creaming), and an increase in density of the globules (bringing them closer to the continuous phase) oweing to the adsorption of a protein membrane. In addition, heat pasteurization breaks down the cryo-globulin complex, which tends to cluster fat globules causing them to rise.
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Old 23-October-2009, 03:51 PM
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And in a related question, howcome 'double cream' is thinner than single cream used to be?

There's some skimming going on somewhere...
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Old 23-October-2009, 05:48 PM
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When I was young, growing up in the inclement weather of Yorkshire, milk was delivered to our house early each morning by a milkman. The milk came in glass bottles sealed with foil caps. My mum liked us to drink full cream milk. The cream used to rise and settle at the top of the bottles, creating a layer about an inch deep, which was frequently eaten by birds that pecked through the foil caps, or fought over by me and my sister to put on our breakfast cereal (yum).
Once you did that, the rest of the milk certainly wasn't "full cream" (what we call "whole," I suspect) anymore.
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Old 23-October-2009, 06:09 PM
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Maggie Thatcher - milk snatcher!

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Old 23-October-2009, 08:01 PM
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The milk, pasteurized, but not homogenized, is about 3% cream (butterfat), depending on your cows. Whole milk has all three percent. 2% milk has 1/3 of the fat removed. 1% has 2/3 of the fat removed. Skim has ~ all the fat removed. If you want cream for your breakfast cereal to be thick, buy heavy cream. Light cream is less viscous. All pupose does the job for a lot of things, including quick whipping into whipped cream, and yes a copper bowl fancied by the French for centuries makes a difference to the stability of the peaks by complexing some of the proteins.
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Old 23-October-2009, 08:13 PM
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When I was young, growing up in the inclement weather of Yorkshire, milk was delivered to our house early each morning by a milkman. The milk came in glass bottles sealed with foil caps.
Small world... Exactly like here [in the 70´s]. Mom would boil the milk, remove the cream that floated to make cookies with it... Good times. Not that I don´t enjoy the neat tetrapaked Parmalat milk.
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Old 23-October-2009, 09:25 PM
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We used to shake the bottle before using the milk to make tea otherwise the first couple of cups from the new bottle were too creamy and the rest too watery. Gold Top was the best for cerial, extra creamy and milk from Jersey cows is creamy as well.
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Old 23-October-2009, 09:40 PM
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I buy whole milk that's unhomogenized for the kids....but I've only been able to find it at the natural foods store.
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Old 23-October-2009, 10:41 PM
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Creamnappers, I tell you.

But then, America brought the world nonfat sour cream. Somehow.
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Old 24-October-2009, 01:19 AM
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What has happened to modern milk to make the yummy creamy layer disappear?

clop
It's called homogenization. The cream is there, but it does not collect on the top of the milk anymore.
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Old 24-October-2009, 06:04 AM
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We use half & half for coffee, omelettes and some baking. The other day I opened a new carton and when I poured it into my coffee, globules of fat floated to the top. I first thought the cream had soured, but it smelled ok and they disappeared when stirred. I decided that the homogenization process hadn't been fully successful. now I shake the carton before pouring and no more globules.
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Old 24-October-2009, 11:43 PM
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Swift and the others - thank you. But still, as a fun-loving adult, and perhaps as a kid who's still struggling to grow up, I can't see the advantage of removing the lovely creamy layer from the top of the milk. Because it's in some cheap waxed cardboard container and can't be inverted every morning? To me, it's just one more fun thing that has been taken away from my life.

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Old 25-October-2009, 09:40 AM
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Here's your cream, clop.

Apparently, they skim the cream from it before the homogenize it. I'm not so sure about that pus angle, though...
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Old 25-October-2009, 09:53 AM
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Creamnappers, I tell you.

But then, America brought the world nonfat sour cream. Somehow.
That stuff always makes my mouth go all tingly after a few taco scoopfuls.
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Old 25-October-2009, 12:34 PM
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We can get 'old fashioned' milk if we want it. In the UK we still have 'Milkmen' who will deliver milk in bottles to your doorstep every morning.
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Old 25-October-2009, 01:21 PM
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I grew up on a farm, and we kept 3-4 dairy cows, which my father hand-milked. In spite of our family of 7 kids, and trading a fair amount of milk off to friends, we always had an excess.

My father used an old International Harvester cream separator on the excess, from which we ended up with literally gallons of cream, which mostly got made into butter, using an old-fashioned hand-cranked butter churn. (Child labor!!!) The cream was amazingly thick, and I grew up with the idea that cream was of the consistency that you could scoop up a dollop on your finger, and it would sit there without running off. Of course, it got used for desserts and cooking as well.

The stuff they sell in stores as cream, heavy or not.... let's just say it isn't.

As an aside, the separator would leave a large pile of foam on top of the skim milk, which my father would scoop off, and feed to the cats. (We always had at least a dozen) The felines would make short work of even a large pile of foam, leaving them bloated and swollen. Us kids would often sit and giggle as they burped up the air until they looked normal again. Funny the things you find entertaining when you don't have a TV.

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Old 25-October-2009, 01:45 PM
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I grew up on a farm, and we kept 3-4 dairy cows, which my father hand-milked. In spite of our family of 7 kids, and trading a fair amount of milk off to friends, we always had an excess.

My father used an old International Harvester cream separator on the excess, from which we ended up with literally gallons of cream, which mostly got made into butter, using an old-fashioned hand-cranked butter churn. (Child labor!!!) The cream was amazingly thick, and I grew up with the idea that cream was of the consistency that you could scoop up a dollop on your finger, and it would sit there without running off. Of course, it got used for desserts and cooking as well.

The stuff they sell in stores as cream, heavy or not.... let's just say it isn't.

As an aside, the separator would leave a large pile of foam on top of the skim milk, which my father would scoop off, and feed to the cats. (We always had at least a dozen) The felines would make short work of even a large pile of foam, leaving them bloated and swollen. Us kids would often sit and giggle as they burped up the air until they looked normal again. Funny the things you find entertaining when you don't have a TV.

TJ
Ha ha that's hilarious. Milk always gives my cat copious explosive diarrhoea.

Someone recently told me that all milk sold in supermarkets, whether it is full-cream, semi-skimmed or skimmed, is first skimmed, then fat is re-added to create 3%, 2% or 1% fat milk for sale. Skimmed milk is more expensive than so-called full-cream milk but in reality it is easier to make skimmed milk than full-cream milk, since full-cream milk is skimmed milk with the fat put back in. Is there any truth in this TJ?

clop
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Old 25-October-2009, 05:34 PM
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That stuff always makes my mouth go all tingly after a few taco scoopfuls.
It's the radiation...

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We can get 'old fashioned' milk if we want it. In the UK we still have 'Milkmen' who will deliver milk in bottles to your doorstep every morning.
Rub it in...

By the way, I see you've turned over a new leaf! Er, petal.

TJ, that was one of the most heartwarming farm stories I've heard in a long while, especially about burping kittens!
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Old 25-October-2009, 05:34 PM
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'Standard' Milk in the UK is 4% fat.

As for the Foaming, that's why Milk Tankers fill from the bottom, pouring in from the top would foam it up.
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Old 25-October-2009, 05:41 PM
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Old 25-October-2009, 06:23 PM
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But still, as a fun-loving adult, and perhaps as a kid who's still struggling to grow up, I can't see the advantage of removing the lovely creamy layer from the top of the milk.
Gah.
Just reading the words "lovely creamy layer" is making me retch. So perhaps that's the answer: there seem to be more people like me around these days, who couldn't swallow your lovely creamy layer for a bet. Maybe it's just part of the general nervousness about dietary fat.

When I was a kid and we got our third-of-a-pint dole of "school milk", which always came in a little bottle with a drinking straw, I'd put my finger over the end of the straw, push it below the level of the cream, and then drink the white milk out from under the (gag) visibly yellower layer above. Then I'd smuggle the bottle back into the crate while concealing the uningested layer from the teacher, because she could be relied upon to disapprove, more or less on principle, of behaviour that was either deviant or ingenious.

In those days, our milkman used to shake our milk a couple of times before leaving it on the doorstep, to dissuade the birds. Blue tits, the main cap-peckers in the UK, are (like most birds) lactose intolerant, so they won't go for milk that's been homogenized.

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Old 25-October-2009, 07:15 PM
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Gah.
Just reading the words "lovely creamy layer" is making me retch. So perhaps that's the answer: there seem to be more people like me around these days, who couldn't swallow your lovely creamy layer for a bet. Maybe it's just part of the general nervousness about dietary fat.

When I was a kid and we got our third-of-a-pint dole of "school milk", which always came in a little bottle with a drinking straw, I'd put my finger over the end of the straw, push it below the level of the cream, and then drink the white milk out from under the (gag) visibly yellower layer above. Then I'd smuggle the bottle back into the crate while concealing the uningested layer from the teacher, because she could be relied upon to disapprove, more or less on principle, of behaviour that was either deviant or ingenious.

In those days, our milkman used to shake our milk a couple of times before leaving it on the doorstep, to dissuade the birds. Blue tits, the main cap-peckers in the UK, are (like most birds) lactose intolerant, so they won't go for milk that's been homogenized.

Grant Hutchison
I'm just amazed that your last sentence got through the auto-censor.
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Old 25-October-2009, 07:16 PM
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I'm just amazed that your last sentence got through the auto-censor.
Now you mention it, so am I.
Here is one of the little fellas at work, just to demonstrate I haven't made the whole thing up as some sort of experiment.

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Old 25-October-2009, 08:56 PM
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Swift and the others - thank you. But still, as a fun-loving adult, and perhaps as a kid who's still struggling to grow up, I can't see the advantage of removing the lovely creamy layer from the top of the milk.
So that everyone drinking a glass of milk from that container always actually gets the percentage of fat the label declares it to have. Especially since, given that I drink 2%, means that I don't want a creamy layer. If I wanted a creamy layer, I'd drink milk with more fat in it.

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Ha ha that's hilarious. Milk always gives my cat copious explosive diarrhoea.
Most adult mammals are lactose intolerant.
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Old 25-October-2009, 09:16 PM
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Most adult mammals are lactose intolerant.
Fortunately, I'm not one of them. I've cruised through two gallons of milk a week for the last twenty years.

I've got good bones. The muscles tear loose before the bones break, as I found out from jumping down from about twelve feet up. (What was I thinking?)
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Old 25-October-2009, 09:31 PM
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Most adult mammals are lactose intolerant.
I read somewhere that so are adult humans if they haven't continued drinking milk after being weaned.

I wonder how many other mammal species can adopt to drinking milk as adults too.

Fermented milk products are btw. reasonably safe for cats, mine are suckers for cheese.
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Old 25-October-2009, 09:35 PM
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The gene which permits lactose tolerance in humans is believed by some to be one of our most recent evolutionary adaptations that actually spread through a large amount of the population. Could be.
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Old 25-October-2009, 09:53 PM
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Fermented milk products are btw. reasonably safe for cats, mine are suckers for cheese.
The fermentation largely clears the lactose, so animals that lack the lactase enzyme can tolerate most cheeses without getting osmotic diarrhoea. (Birds can also eat cheese with no ill-effects.)
Our old cat drank nothing but milk, from kittenhood and throughout his long adult life. Quite bizarrely, he never mastered water, despite repeated efforts to get him to switch. He'd eye the reflective surface suspiciously, immerse his face in an uncoordinated way, and then flee in disgust.

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Old 25-October-2009, 10:06 PM
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Did he tolerate it without getting diarrhoea?
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