Dilution — Glazing & Mixing
Ice glaze padding the scale and cheaper species blended into a premium pack.
Dilution makes the pack appear larger or more premium than it actually is. It operates in two distinct modes: physical dilution via excess ice glazing, and compositional dilution via species mixing. Both defraud the consumer of value they paid for.
Frozen prawn glazing — a protective ice coating — is legitimate at 5–10% by weight and serves a genuine quality-preservation function. Industry surveys regularly find 30–40% glaze on retail product. Species mixing blends cheaper fish into a premium-labelled product: the average species composition may technically match the label, but the consumer paid premium prices for filler. Both require only basic testing to detect — yet both persist because labelling requirements leave the information gap open.
Why it persists
"Net weight after deglazing" is rarely declared on retail packaging, so consumers pay for water weight they discard at home. Species mixing requires DNA testing to detect — a method unavailable to the shopper at the counter, and rarely deployed by regulators at the frequency the problem demands.
Red flags
- Pack feels significantly lighter after thawing than the sealed weight suggests
- Visible thick ice coating on individual pieces even before full thaw
- Inconsistent piece-size, colour, or texture in a "single species" pack
- No declared net weight after thaw or glaze percentage on the label
- Unusually low price-per-kilogram for a premium species
Counter-measures
- Mandatory net-weight-after-thaw labelling on all frozen seafood
- Maximum glazing percentage caps (e.g. 12%) enforced at inspection
- DNA spot-checks on premium single-species packs at retail
- Glaze percentage mandatory declaration on commercial documentation
Who needs to act — and how
Glazing and species mixing both require active intervention — consumers, buyers, and regulators each play a role.
What you can do
- Weigh frozen product before and after thawing — significant loss indicates excess glaze
- Look for "net weight after thaw" on the label before purchasing
- Report significant weight discrepancies to consumer protection authorities
What you can do
- Require supplier declaration of glaze percentage in procurement specifications
- Commission periodic DNA testing on single-species premium lines
- List net drained weight alongside gross weight on all frozen labels
What you can do
- Declare glaze percentage on all commercial documents and product specs
- Implement incoming product glaze-testing as part of supplier qualification
- Maintain separate production lines for different species to prevent commingling
What you can do
- Mandate net-drained-weight declaration on all consumer-facing frozen product
- Set and enforce maximum glaze percentage caps with inspection testing
- Include DNA species verification in annual seafood surveillance programs