Extraneous vegetable matter, usually abbreviated EVM, means plant material in the pack
that is not the specified article: leaves, stalks, husk, silk, pod fragments, weed
material, or pieces of a different crop grown or handled nearby.
It is a quality defect, not a food safety defect, and that distinction decides how it
is handled. EVM gets a percentage limit in the specification and is dealt with
commercially. Hard foreign matter – metal, glass, stone, plastic – is a safety issue
with a different escalation path, a detection requirement and, potentially, a
notification obligation. Specifications that lump the two together create confusion at
exactly the moment clarity is needed.
Write an EVM limit with three components. A definition, so the person examining the
sample knows what to count. A limit. And a counting basis: by weight or by count, and
of what sample size. “Maximum 0.5 per cent” is not a specification until you say 0.5
per cent of what, measured how.
It is also worth naming the categories separately where they matter. On sweet corn,
silk and husk behave differently and buyers care about them differently. On leafy
products, stalk is the issue. A single aggregate figure hides the defect that actually
generates complaints.
Optical sorting removes a great deal of EVM on a modern line, but it works on colour
and shape, so material that resembles the product survives it.