RSSExpiry dates on food
01 Mar 2009
When traveling, my packing-list includes emptying out the fridge before heading to the airport. Fortunately, I have almost nothing perishable in the fridge (chocolate, cliff bars, coffee, beer, vodka all last a *long* time), so this is quick.
However, when throwing out the last of the milk, I noticed the expiry date:
- A typo; ARP should be APR! Huh!? I always assumed those dates were all computer timestamped, but is there really a human putting in a new expiry date every day? Has anyone else ever noticed something like this?
- Since when did milk last over a month? This milk was bought slightly over a week ago (approx Feb 20th) and claims to be good until April 5th, which is approx 6 weeks!?! How is that possible? I’m used to milk only being good for a few days.
If you don’t already know of it, check out www.stilltasty.com. It answers all important questions like how long will pizza safely last when frozen / when in fridge / when left out at room temperature. 
Justin Dolske
01 Mar 2009 @ 14:24:11
Bad news, that milk went bad on Arpil 9th, 2005!
Seriously, though, it just depends on how it’s pasteurized. For example: http://en.wikipedia.org/wiki/UHT
Specialty milk (lactose-free, organic, etc) that presumably doesn’t sell as quickly has been produced with a longer shelf life for quite some time… I’ve taken to looking for it because I have the bad habit of buying a carton and forgetting about it for a week or two. It also seems to last longer once opened.
Ian Thomas (thelem)
01 Mar 2009 @ 14:28:13
Or ARP should be mAR? Only one letter out and would explain point 2.
Still doesn’t explain the stupid date order that America insists on (everywhere else is in ascending order – day month year)
Jeff Walden
01 Mar 2009 @ 15:17:10
Organic milk lasts longer than normal milk for some reason. The claim I’ve heard is that lack of pasteurization has something to do with it, but I haven’t investigated to determine what exactly causes this.
Speaking of which, I should make something that needs milk right now, seeing as I have a partial half gallon that’s about to go bad…
anonymous
01 Mar 2009 @ 15:17:29
If you buy fresh milk it only lasts for several days, but UHT milk lasts for several weeks. For more info, see Wikipedia:
http://en.wikipedia.org/wiki/Uht_milk
chris
01 Mar 2009 @ 15:24:36
in terms of the shelf-life, it’s so long because this particular variety of milk has been subjected to ultra-pasteurization (UHT)
http://en.wikipedia.org/wiki/Pasteurization#Pasteurization_of_milk
Jo Hermans
01 Mar 2009 @ 15:46:51
Never heard of UHT milk (the label says ‘ultra pasteurized’, although that not entirely correct) ? UHT milk can have a shelf life of 6 to 9 months. If it’s still closed, it doesn’t need to be stored in the fridge either.
http://en.wikipedia.org/wiki/UHT
Boris
01 Mar 2009 @ 17:03:07
Some of the ultra-pasteurized stuff that’s sealed well will keep a good long while. As long as you don’t open it, of course.
chithanh
01 Mar 2009 @ 18:31:17
The technique to increase shelf life of milk is called pasteurization.
http://en.wikipedia.org/wiki/Pasteurization
RichB
01 Mar 2009 @ 23:03:30
http://www.stilltasty.com/fooditems/index/18703
Not entirely accurate. I heard the head of marketing for Worcestershire sauce say on Radio it simply got better and better after the Best Before date.
In fact, that’s how it was invented!
Kim Sullivan
02 Mar 2009 @ 00:38:17
In europe, UHT milk (http://en.wikipedia.org/wiki/Ultra-high-temperature_processing) is quite common, and has a shelf life of several months, if left unopened. Once you open it, it acts more like fresh milk but lasts about a week or so (depends on if you drink your milk directly from the carton
NM
02 Mar 2009 @ 03:02:13
If it’s ultra high temperature pasteurized milk, it could last months, unopened, at room temperature.
David Baron
02 Mar 2009 @ 03:06:36
Notice the “Ultra Pasteurized” on the box. That means it was pasteurized well enough that it will last for six weeks (or whatever) unopened, but there’s probably small print on the side that says it only lasts a week once opened. (That’s also a “Sell by” date rather than a “Drink by” date.)
lockoom
02 Mar 2009 @ 03:28:16
1. Well, someone programmed this machine and did it wrong.
2. http://en.wikipedia.org/wiki/UHT
Anonymous
02 Mar 2009 @ 05:03:51
That particular brand, Horizon Organic, always seems to have expiration dates two weeks or so longer than every other brand.
Frank Hecker
02 Mar 2009 @ 05:25:02
I was curious about this too, so googled it. Horizon uses ultra-pasteurization and various other related techniques to extend the shelf life of its products; see http://www.horizonorganic.com/site/faq/products_org_milk_process.html
Richard Klein
02 Mar 2009 @ 06:37:08
I use to work at a spice company and I helped develop there date coding software. You actually have to have some pretty high tech manufacturing equipment to allow the lines to communicate with your erp. Also, there were lots of instances where we needed to allow manually entering date codes versus using what was generated in the erp.
Matt Brubeck
02 Mar 2009 @ 08:38:55
UHT milk has a much longer shelf life than normal milk. Because there are fewer organic dairies, they have to ship their milk to stores farther away. So organic milk in stores is often UHT processed.
McCow
02 Mar 2009 @ 12:34:50
There are one or two new processes available which push the time limit for “fresh milk” up to around two to three weeks. As far as I remember one process uses special micro-filtering in order to get rid of milk components which decay rather quickly. The result is fresh milk that is good for a longer period. But I haven’t yet to see six weeks…
Travis
02 Mar 2009 @ 16:36:56
That’s not a typo. With ulta-pasteurization and special packaging the milk really is good for over a month. I buy organic milk for exactly that reason…
Dylan
02 Mar 2009 @ 17:30:39
I think that’s a sell-by date–as in, “will last *at least* this long while sealed. Past that, no commercially-backed guarantees.” Just guessing.