The majority of expiration dates are pure nonsense, based on nothing, that are added to encourage people to throw out old products and buy new ones. They are entirely at the discretion of the manufacturer.
The only expiration dates with meaning are those on medically relevant foods – baby formula, meal replacements, medical supplements, or things that a doctor would describe. Those are determined by clinical testing of effectiveness.
Company makes some sort of food product. They bear a legal obligation to list an expiry date on the packaging and within reason (ie not applying to cases where the packaging is compromised or tampered with in some way) it has to be generally true. Companies care about shelf life because this determines a lot of things about the viability and pricing of their product. Longer lasting products are cheaper and have more chances of being sold. Short lived products are more expensive and have higher chances of going unsold.
Company runs some tests and then they print an expiry date that’s low balling their test results by a lot. This way they can “guarantee” that within this timeframe the food will definitely not go bad. This doesn’t mean that it cannot last longer, it just means that they bear no legal liability for anyone who eats an expired product and has adverse effects from it. For example there are a lot of canned or frozen or freeze dried foods that have been found to be edible many years, decades, or even more than a century after production. This doesn’t mean that every single one will be and it also doesn’t mean any company would assume such a liability and print an expiration date numbering decades from today. Even testing for something like that would take decades in itself so no company bothers.
Also its not expiry date but a best before, so they not only take into consideration how long its edible, they also take into account texture, colour and flavour.
Often food is safe to eat but discolours after some time and doesn’t look like its supposed to do. Or you get a pool of water on top of the food but just a stir fixes it.
And often enough the food just gets a label slapped on, how long its at its best and this can be month before any of the mentioned changes happen. Just so you buy it more frequently.
Stuff like meat and dairy we have hundreds of years of experience with, so we have a very good idea of how long it lasts in various conditions. We track when it was produced and set the date accordingly. That gallon of milk might be a mix of milk from 100 cows, but it was all produced on the same day, so we’re confident how long it’ll last.
Stuff like baked goods is pretty straightforward too. That stuff just doesn’t last all that long and its really easy to figure out.
When you get to something like Kraft Mac and Cheese, you reach a point where the ingredients start to separate and the coloring gets weird. We’ve got a rough idea of how long that takes and put a conservative date on it. A two year old box is pretty likely to be bad, but the date on the box is probably one year from manufacture.
Some stuff like honey or salt doesn’t really go bad. Federal law requires companies to keep a sample from each production lot for a certain amount of time past the expiration date. This is in case the lot needs to be tested to track issues such as contamination concerns. In these cases, the producer says “we don’t want to store more than X samples” and puts a date on it. That 10 year old jar of honey is probably safe, but legally the manufacturer is no longer liable if you get sick.
it is based on type of product and also “best before” dates are required by law
but it is mostly guessed, for example bread, pastry and such that is fresh and no preservatives gets 2-7 days, but packaged bread and some other stuff like 7 days croissant can have 1+ year before they’re “expired”, fresh milk usually gets 7 days but if it is pasteurized, sterilized it can have 6+ months of shelf life
the type of packaging also plays role in how long it can sit on shelf before it is “expired” like canned food has much longer shelf life than plastic or paper but not only because it preserves food better it is also important to know how long before that materials starts to degrade
In the UK there are Best Before dates and Use By dates, I do a food rescue, where we pick food up from supermarkets put it on an app and people come and pick it up, we can’t give out Use by After the date but we can for Best Before, I just binned some sliced bread today that’s over 2 weeks past it’s best before, over 1/2 was mouldy – had some eggs that are a month past their use by, not gone rotten perfectly fine, similar with milk… sniff test it… does it smell bad – nope, taste a bit, does it taste bad… nope, you probably good
A couple of “snack points”: believe it or not, potato chips have very short lives in the store. One reason Frito Lay is so successful is their efforts to police their shelves and make sure only fresh chips are on the shelf. When in doubt, they pull them. Back they go.
The life of snacks, once open go this way: shortest life= potato chips, lasts longer=tortilla chips, lasts much longer=pretzels.
A good package makes a good product. Multilayer bags and if needed, foil packaging can keep snacks fresh longer. There is a reason generic products come in single layer mostly clear packaging; it is cheaper. But not as preserving as a more complex package.
Comments
The majority of expiration dates are pure nonsense, based on nothing, that are added to encourage people to throw out old products and buy new ones. They are entirely at the discretion of the manufacturer.
The only expiration dates with meaning are those on medically relevant foods – baby formula, meal replacements, medical supplements, or things that a doctor would describe. Those are determined by clinical testing of effectiveness.
Company makes some sort of food product. They bear a legal obligation to list an expiry date on the packaging and within reason (ie not applying to cases where the packaging is compromised or tampered with in some way) it has to be generally true. Companies care about shelf life because this determines a lot of things about the viability and pricing of their product. Longer lasting products are cheaper and have more chances of being sold. Short lived products are more expensive and have higher chances of going unsold.
Company runs some tests and then they print an expiry date that’s low balling their test results by a lot. This way they can “guarantee” that within this timeframe the food will definitely not go bad. This doesn’t mean that it cannot last longer, it just means that they bear no legal liability for anyone who eats an expired product and has adverse effects from it. For example there are a lot of canned or frozen or freeze dried foods that have been found to be edible many years, decades, or even more than a century after production. This doesn’t mean that every single one will be and it also doesn’t mean any company would assume such a liability and print an expiration date numbering decades from today. Even testing for something like that would take decades in itself so no company bothers.
So basically expirations are just a safe bet.
Sometime they do or did to test how long it took.
But often they are just guessed.
Also its not expiry date but a best before, so they not only take into consideration how long its edible, they also take into account texture, colour and flavour.
Often food is safe to eat but discolours after some time and doesn’t look like its supposed to do. Or you get a pool of water on top of the food but just a stir fixes it.
And often enough the food just gets a label slapped on, how long its at its best and this can be month before any of the mentioned changes happen. Just so you buy it more frequently.
Stuff like meat and dairy we have hundreds of years of experience with, so we have a very good idea of how long it lasts in various conditions. We track when it was produced and set the date accordingly. That gallon of milk might be a mix of milk from 100 cows, but it was all produced on the same day, so we’re confident how long it’ll last.
Stuff like baked goods is pretty straightforward too. That stuff just doesn’t last all that long and its really easy to figure out.
When you get to something like Kraft Mac and Cheese, you reach a point where the ingredients start to separate and the coloring gets weird. We’ve got a rough idea of how long that takes and put a conservative date on it. A two year old box is pretty likely to be bad, but the date on the box is probably one year from manufacture.
Some stuff like honey or salt doesn’t really go bad. Federal law requires companies to keep a sample from each production lot for a certain amount of time past the expiration date. This is in case the lot needs to be tested to track issues such as contamination concerns. In these cases, the producer says “we don’t want to store more than X samples” and puts a date on it. That 10 year old jar of honey is probably safe, but legally the manufacturer is no longer liable if you get sick.
it is based on type of product and also “best before” dates are required by law
but it is mostly guessed, for example bread, pastry and such that is fresh and no preservatives gets 2-7 days, but packaged bread and some other stuff like 7 days croissant can have 1+ year before they’re “expired”, fresh milk usually gets 7 days but if it is pasteurized, sterilized it can have 6+ months of shelf life
the type of packaging also plays role in how long it can sit on shelf before it is “expired” like canned food has much longer shelf life than plastic or paper but not only because it preserves food better it is also important to know how long before that materials starts to degrade
In the UK there are Best Before dates and Use By dates, I do a food rescue, where we pick food up from supermarkets put it on an app and people come and pick it up, we can’t give out Use by After the date but we can for Best Before, I just binned some sliced bread today that’s over 2 weeks past it’s best before, over 1/2 was mouldy – had some eggs that are a month past their use by, not gone rotten perfectly fine, similar with milk… sniff test it… does it smell bad – nope, taste a bit, does it taste bad… nope, you probably good
A couple of “snack points”: believe it or not, potato chips have very short lives in the store. One reason Frito Lay is so successful is their efforts to police their shelves and make sure only fresh chips are on the shelf. When in doubt, they pull them. Back they go.
The life of snacks, once open go this way: shortest life= potato chips, lasts longer=tortilla chips, lasts much longer=pretzels.
A good package makes a good product. Multilayer bags and if needed, foil packaging can keep snacks fresh longer. There is a reason generic products come in single layer mostly clear packaging; it is cheaper. But not as preserving as a more complex package.