The food business operator sets it, and must be able to justify it. Regulation (EU) No 1169/2011 requires a date of minimum durability, a “best before” date, for frozen vegetables, but it does not state a number. The 18 to 24 months commonly seen on frozen vegetable packs is a shelf life the operator has justified through storage trials, not a figure prescribed by law.
Justification normally rests on three things. A storage study holding product at the declared storage temperature, usually minus 18 degrees Celsius or colder, with sensory, colour, texture and where relevant vitamin assessments at defined intervals across and beyond the intended life. An abuse study exploring what a realistic temperature excursion does. And a safety rationale, which for a blanched frozen vegetable is straightforward because microbial growth does not occur at frozen temperatures; the limiting factor is quality, not safety.
What actually ends the useful life is quality drift: colour loss, off-flavours from residual enzyme activity where the blanch was marginal, texture softening, moisture migration and freezer burn from packaging that is not a sufficient moisture barrier, and ice glaze or clumping from temperature cycling. That is why shelf life is a joint statement about the product and the pack, and why changing the film structure invalidates the previous shelf life claim.
Two practical points for buyers. First, the declared life is conditional on the declared storage temperature; a chain that runs at minus 12 degrees Celsius does not deliver the labelled life, which is why intake temperature and the transport temperature record are checked. Second, specify minimum remaining shelf life on delivery separately, commonly expressed as a share of total life such as 75 per cent, because a compliant date code on an old lot is still a commercial problem.
Where the category rules require a date of freezing in addition to the best before date, it must come from the production record rather than from an artwork template.