Solving Milk Souring Mystery in Fridge

  • Thread starter Greg Bernhardt
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In summary, the author suggests that if you are buying milk from a store, try to buy it when you are there, and if it's cold outside, the milk will last longer.)
  • #1
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For the past year I haven't been able to keep milk in my fridge for more than 4-5 days. I always buy the freshest milk, not expiring for a couple weeks from purchase. However, the milk sours in my fridge in 4-5 days no matter what brand or size of milk. After 4-5 days the top of the milk is filmy and smelly. Even more drastic I bought two 12oz bottles of milk yesterday. I drank one last night and it was fine, but I went to drink the second this morning and it was rank, I poured it down the drain and it was chunky. My fridge cold level is 7 out of 10. 10 being coldest. I have no problem keeping any other foods for a long time and everything feels cold to the touch. Anyone have ideas why I can't keep milk for long, it's sooooo annoying!
 
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  • #2
We should buy you a cow.
 
  • #3
Radio shack sells a really inexpensive digital thermometer and humidity gauge that records highs and lows. That would tell you if your refrigerator is getting cold and if it is staying cold.
 
  • #4
turbo-1 said:
Radio shack sells a really inexpensive digital thermometer and humidity gauge that records highs and lows. That would tell you if your refrigerator is getting cold and if it is staying cold.

I agree. You might want to look into the temperature of the fridge. It may not be cold enough for the milk in there.
 
  • #5
Random thought -- is your milk sitting right next to the electric light bulb in your fridge? Maybe the switch on the door is defective, and the bulb is staying on, heating just that one part of the fridge. Maybe try unscrewing the bulb for the next couple of weeks, to see if that fixes the problem. And if it does, get a new switch.
 
  • #7
A few potential sources of problems:
1) Do you always buy milk from the same store? Perhaps the store employees are not very vigilant about getting it off the hot loading dock and into the coolers, shortening the shelf life considerably.

2) When you buy the milk, do you pick it up first or last during a shopping trip? Could you be letting it warm up enough in the shopping cart to let the bacteria start growing?

3) What about on the way home? Is it sitting in the hot trunk of the car for a while? I try to keep the milk cold on hot summer days by keeping all the cold/frozen goods together in the same bag(s). Pack it with the frozen peas and ice cream, and put it on the floor of the car interior rather than the trunk so it gets the air conditioning you're getting.

4) Have you thoroughly disinfected your fridge since discovering this persistent problem? You might have one of the bacteria that sours milk growing in a nice culture in there somewhere (have much yogurt with active cultures?) that's getting into open milk containers (doesn't explain the sealed container issue though). I'd suggest pulling everything out and cleaning the entire interior of the fridge with a bleach solution, rinse thoroughly and see if the problem goes away. Keep yogurts and cheeses in sealed bags or containers to prevent cross-contamination.

5) As suggested above, toss a thermometer into the fridge and check that the temperature setting is sufficiently cold for the milk. Also, check the door seal, especially if it's an older fridge. If there's a leak near where you keep the milk (probably the top shelf or door), that part of the fridge may not get cold enough, while stuff down in crisper drawers is freezing (that happened to me once with a leaky door seal...fridge kept running and cooling the bottom, but the top shelf was still a bit on the warm side due to the leaky door seal).
 
  • #8
Really great ideas and things to consider, thanks all, I will return with a followup in a week or so! I need my calcium! :)
 
  • #9
One other factor: if you are buying it from the same place, the temp at which they keep their fridges will factor strongly into how long the milk lasts.

Long ago I read some guideline that compared store storage temperature to longevity. It was like: for every degree above X, milk will spoil Y days sooner. The temp. ranged from optimal (a few degrees above freezing) to just below room temp., while the longevity ranged inversely from a week or more down to less than a day. (I say all this in long form because I don't want to provide misinformation in the form of an equation).
 
  • #10
Also check the expiration date on the milk carton, and storage conditions where one buys the milk.

I used to work in a grocery store, and when I stocked the dairy section, I was told to put the older stuff in the front and hold back on the fresh so the store could get rid of the stuff about to expire. I didn't like doing that, and if someone asked, I gave them the fresh dairy product.

It's best to get one's milk from the back of the dairy case where it is colder, and probably fresher.

Certainly one needs to verify the operation of one's refrigerator at home. One can get an inexpensive digital thermometer, or even conventional liquid one, at a local pharmacy/apothecary/drug store.
 
  • #11
I reckon your fridge has been contaminated by milk drinking nasty bugs.
 
  • #12
I think Dave may have hit the problem, if not, I'll go with Brewnog. This is something I could see happening in Wolram's fridge.
 
  • #13
Maybe you need to move closer to some cows! Oh, wait a minute...
 

FAQ: Solving Milk Souring Mystery in Fridge

What causes milk to sour in the fridge?

Milk contains bacteria that can grow and multiply when exposed to warm temperatures, causing it to spoil. When stored in the fridge, the temperature slows down the growth of bacteria, but if the fridge is not cold enough, the bacteria can still grow and cause the milk to sour.

How can I prevent my milk from souring in the fridge?

Make sure your fridge is set to the proper temperature, ideally between 34-39°F. Keep your milk in its original container and avoid transferring it to different containers. Also, be sure to close the milk container tightly after use and never leave it out at room temperature for an extended period of time.

Can I still consume sour milk?

It is not recommended to consume sour milk as it may contain harmful bacteria that can cause food poisoning. It is best to discard any milk that has a sour smell or taste.

How long can milk last in the fridge before it sours?

The shelf life of milk can vary depending on the type of milk and how it is stored. Generally, pasteurized milk can last up to 5-7 days in the fridge, while ultra-pasteurized milk can last up to 2-3 weeks. However, it is important to always check the expiration date on the milk container and use it before that date.

Can I freeze milk to prevent it from souring?

Yes, milk can be frozen to extend its shelf life. However, freezing can change the texture and taste of the milk, so it is best to use it for cooking or baking rather than drinking. It is important to thaw frozen milk in the fridge and use it within a few days after thawing.

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