These are out of date but they are probably okay to eat if you want them.
Out of date also means that something has past their expiry date. In most cases dry food is usually okay to eat after said date. So to say to your co worker you can imply that they are probably okay to eat, meaning you're not sure but they most likely won't do them any harm.
out of date＝賞味期限切れ
乾燥してある食品であれば、記述された賞味期限を過ぎていてもたいてい食べることができます。
probably okay to eat＝確実ではなけれど、お腹を壊したりはしないと思うからよければ食べてね、という事を示唆する言い方です。
These are past their use-by date, but feel free to take them if you want.
These snacks are past their best, however, if you want you can eat them.
The snacks have expired, but if you are not worried you can have them.
"Use-by date" is the common way to refer to a product that is past it's best. The "Use-by date" is the date printed on the packaging that explicitly dictates when a product can be sold by and is considered not good to eat once the date has expired.
In general conversation you can also say the products are past their best or have expired. Its clear and understandable what you mean.
賞味期限の切れた商品を表すときは、一般的に "Use-by date" が使われます。
"Use-by date" は、商品を売ることのできる期限のことで、商品のパッケージに記載されています。この日付を過ぎるとおいしく食べられないと考えられています。
普段の会話では、'the products are past their best'（その商品は賞味期限が切れている）や 'the products have expired.'（同）と言うこともできます。これでもはっきり意味が伝わります。
The sweets are already past their expiration date but if you don't care about that, you can eat them.
The sweets have expired, but if they still taste okay, you can eat them.
Expiration date means the date when food is no longer safe to eat but this differs from one food to the other. For example: when milks reaches its expiration date then it always goes bad and sour and is no longer safe to drink. But sometimes food that is dry would be safe to eat even after two or three days especially if they have been stored in the freezer. So you would tell your coworker to taste the sweets, maybe they still taste good and okay despite passing the expiration date!
Hope this helps!
These snacks have passed their expiry date but they are probably safe to eat
These snacks have passed their use-by date but they are probably still good
English speakers often use words like "expiry date", "use-by date", and "best-before date" interchangeably, although they have slightly different definitions. Many people think that expiry dates are a marketing ploy to make us buy more products because we mistakenly believe our food has "gone bad" or "spoiled".
You can eat these, but they are past their best before date.
These are past their best before date, but you can have them if you'd like.
To explain to someone that they can eat a snack if they don't mind that it has passed the best before date, you can do so in the following ways:
"You can eat these, but they are past their best before date."
"These are past their best before date, but you can have them if you'd like."
「賞味期限を気にしないならお菓子を食べてください」は次のように言えます。
"You can eat these, but they are past their best before date."（これ食べてもいいですけど、賞味期限は切れています）
"These are past their best before date, but you can have them if you'd like."（賞味期限は切れていますけど、食べたかったらどうぞ）
If you're not fussy about the best before date, please help yourself
It's up to you if you want to eat stuff with an expired date
When talking about some snacks to a coworker, the snacks are past their best before date. You want to tell your coworker that he/she can eat the snacks if he/she isn't worried about the best before date. You use one of the abovementioned phrases.
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