When does milk go bad?
 

With 4 kids, we've been buying milk by the gallon for the last 15 years. As 2 kids have moved out, we haven't dropped back to the smaller size container, and it now sits longer in the fridge. As Mrs BamaVol and I were finishing breakfast this morning, she made a face and asked what was the expiration date on the milk. I looked and it was 7 days ago. Both of us had a bowl of cereal with a half cup or so of milk. I hadn't noticed anything myself. She didn't until she took a spoonful of milk after the cereal was gone from the bowl. She sniffed the milk container and gagged.

It's 2 hours later, and other than a little "growly in the bowely", we're both ok.
I've always viewed the date on the milk as a sell by date.

When does the milk become dangerous?

When you open it up and it's lumpy and smelly...you shouldn't drink it. :D

Seems to me that I can drink milk about a week past its expiry date...I believe skim milk last longer than, say, whole milk.

I go by the smell test and if I detect the slightest hint of something foul, I dump it down the drain.

I agree with UNITED959 on the smell test, but I don't know when it actually becomes dangerous, though if I were to see some green on the milk, I would assume that it has passed that point.

Some companies do or have in the past advertised their milk to be good for a week past its "sell by" date. Pet and King Soopers come to mind, but maybe only for the paper cartons, not the plastic jugs. I have found other milk, particularly some in plastic jugs to be turning on or before the date printed. I don't know whether different milk bottlers use different schemes for the date on the container, but it would seem so. For regular grocery-store milk, I've generally found the paper cartons to hold up better than the plastic containers.

I'm fortunate enough to live near a dairy store, who's milk is very recently "harvested" and bottled in glass. Their code dates are accurate to slightly conservative (i.e. I don't remember any of their milk turning before the code date). Milk I bought on 8/17 has a code date of 9/2, so that's about 16 days, which would seem a reasonable estimate for shelf life of milk, if kept properly refrigerated. If I look for milk in a regular grocery store, it is a challenge to find a carton with a code date of more than a week, which may suggest how much shipping time is involved.

I don't know if this is really true or not, but I think milk will stay better longer depending on the amount left in the container. E.G. if there is about an inch left it might go bad faster than a full container. I can usually start to taste milk going bad around the expiration; however that is usually when I am getting near the end of it.

Brian

I have noticed that organic milk lasts a lot longer than regular...as in expiration dates ~3 weeks out. I'm not sure what the organic-ness has to do with shelf life, but that's what I've observed.

Likely, because it's only bottled in small quantities for folks willing to pay the price, it reaches the store shelf more quickly and sits there a shorter period of time.

Them crafty Uropeens will sell you milk which lasts nearly forever, and the container doesn't even glow in the dark.

For those of us reduced to skim or 1% milk, what flavor remains is so minimal that one could hardly tell when it had soured.

....And there's naught wrong with drinking sour milk. After all, we use sour cream, eat cheese, butter and any number of "soured" milk products. ^

When does milk go bad?
 

...when it holds up the lettuce. :D

I'm here all week folks, tip your waiters.

On a tangent, I've had much better luck with milk bottled in glass, rather in plastic. I get my milk from Ronnybrook Farms, and my experience has been that when I buy it from them at the farmers' market in glass, it'll last a few days past the date, but when I buy their milk in plastic from Fresh Direct (a NYC internet grocery) it'll go nasty basically on the date. Then again, that may say more about Fresh Direct than it says about glass vs. plastic.

I also work on the smell test, and the "creates chunks when you pour it into coffee" test. And the "itty bitty sip" test when I don't trust my nose.

There's one brand of organic milk in the store (Amish something, I think) that always has a really long date on it--I wonder if they've done some sort of extra processing?

The brand you buy may be ultra-pasteurized, which is the common practice with lactose-free milk for some reason. This extends the expiration to about 3-4 weeks.

Are you talking about the stuff in a carton that sits on an unrefrigerated shelf in the store? I've been curious, but we still consume quite a bit of milk and opt for the big cheap jugs of 2%. For sure, I will be buying the smaller big jugs in the future.

I'm not sure I would trust the uncontrolled deterioration of dairy in my refrigerator as much as factory cotrolled, government regulated and inspected production of sour cream, yogurt and cheese. I don't know that the product that results from ignoring expiration dates at home is any of those. :eek:

Final chapter, hopefully: it's been 7 hours and I have no symptoms. I think the milk was ok although possibly well on its way to bad.

I use the week-beyond rule as well.

Suggestion... buy the half gallons of organic milk... it costs more, but it's good for like 1 1/2 months.

I'm excited to finally find a topic where I can make a contribution.

That said, I can only add a few points. The most common way to shorten the "shelf life" of fresh milk is by improper handling. Milk should be stored at a temperature of 41 degrees F(5C) or less. Food service guidelines state that if it remains above this temperature for more than 4 hours, there is a significant risk of dangerous levels of pathogenic microorganisms (bugs).

Experience tells me that milk that has remained well chilled will usually last 5-7 days past the "sell-by" date. In areas such as my home (Texas), it can be hard to get it back from the store in the summer at the proper temperature. Can you say - I hate warm milk! ;)

If you are in good health and are not immune compromised, you can probably deal with a little sour milk with no lasting effects.

I usually ignore the sell by date and give up about a week after opening, as at that point there is usually the beginnings of an off odor. This is with standard store brand skim milk. We usually buy it in quarts. :D (I eat my morning cereal during the week here at the office, so I'll buy a quart here. Then we buy a quart at home for the weekend.)

There's a possibility different container materials may lengthen the shelf life (the cheapo store brand is in clear plastic jugs, even for the quarts and half-gallons, vs the opaque plastic or the paperboard containers), but it's not worth the price differences or searching around in different stores to find this sort of thing.

I wouldn't make a blanket generalization like this. For instance, sour cream is cream that's fermented with specific bacteria. If other types of bacteria start to grow in it, it will go bad, which is why sour cream comes with an expiration date. Similarly, blue cheeses contain specific molds that are safe to eat, but if your cheddar starts growing mold, that is something you shouldn't eat. So some of what grows in your milk may be safe, some of it may not. Unless you know for sure, it's safest to toss it.

If you buy milk in NYC, it has two exipration dates on it--one for New York City, and one for all other areas. NYC apparently has stricter regulations on how long after pasteurization milk can be sold, so when milk goes bad depends on who you ask.

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