Increments, composite, reduction, retention
Take many increments across the whole lot, combine them into a bulk sample, reduce by riffle divider or quartering into laboratory and retained portions, then seal, label and store the retained portions under conditions that preserve them.
Heterogeneous contaminants demand more increments
For mycotoxins and foreign matter, contamination sits in hot spots. Increasing increment count reduces sampling error far more effectively than repeating the laboratory analysis on the same composite.
Who samples, and when
Independent surveyor sampling at load port, at discharge, or both, changes the evidential weight of a later claim. Agree the sampling party, point and method in the contract rather than negotiating it after a problem appears.
What to verify
- —Written sampling plan with increment count and pattern
- —Sampling point and party named in the contract
- —Sealed, labelled retained samples held by both parties
- —Retention period long enough to cover the claim window
Typical risks
- —A non-representative result driving a wrong accept or reject decision
- —A claim collapsing because the retained sample was not properly sealed
Common mistakes
- —Grab sampling from an accessible point only
- —Discarding retained samples once the cargo is accepted
Frequently asked questions
How long should retained samples be kept?
At least through the feeding period of the material plus the contractual claim window; many mills retain for the shelf life of the resulting feed and the animal products derived from it.
Related topics
A certificate of analysis is a lot-specific record of tested parameters, methods and results; a generic or typical-values sheet is a marketing document, not a certificate.
Independent verification means testing the delivered lot at an accredited third-party laboratory using the contractual reference methods, on a properly drawn and retained sample.
Independent inspection documents the physical condition of cargo, hold or container, packaging and loading at a defined moment, creating the evidence base for acceptance and claims.
Build a structured RFQ with the parameters, tolerances and verification steps written in — free for buyers.
Start your RFQTechnical parameter names and analytical method references are kept in English because they are quoted verbatim in contracts, certificates and international standards.
Educational reference. FeedMatch Group does not rank, recommend or endorse manufacturers.
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