Here's a good explanation on the rules and differences between that and which: Read here.
It all basically boils down to this quote from the article:
If you need the clause to maintain a sentence’s meaning, then use that.
The clause in your example sentence is here in bold:
"Any product that includes more than 15 per cent of the daily recommended intake of each ingredient will get a label."
If we can remove the clause and the sentence still holds its meaning, then we should use which.
If removing the clause changes the sentence's meaning, then we should use that.
Here's your sentence with the clause removed:
"Any product will get a label."
This changes the meaning of the sentence completely, so use that, not which.
One exception to this rule as stated in the same article is:
- Which can be used restrictively when it’s preceded by a preposition.
"restrictively" refers to the clause being needed in the sentence.
So if you really want to use which, the acceptable sentence would become:
"Any product of which includes more than 15 per cent of the daily recommended intake of each ingredient will get a label."