Why Is the Bulk Shipment Different From the Sample?
The sample you approved and the container you receive are rarely made the same way. A sample is a few hundred grams from selected fruit, dried in one batch and checked piece by piece. A container is several tonnes from many fruit lots, dozens of drying batches, several shifts and weeks of storage and shipping. Some difference is certain. The question is whether it sits inside limits both sides signed before production.
It is the complaint that costs buyers the most trust, and it is almost always a contract problem before it is a quality problem. Without written tolerances, you have no basis to reject a lot that looks different. With them, the discussion is a measurement, not an opinion.
Where does the difference between sample and container come from?
From five places, each of which can be controlled once it is named.
- The fruit. Pineapple is a crop, not a resin. Sugar, acidity and colour change with farm, harvest date and season. In our experience, dry-season fruit reads noticeably sweeter than rainy-season fruit, and freeze-dried colour moves from deep gold to pale yellow with it. A sample made in February from high-Brix fruit and a container made in July from lower-Brix fruit will not match unless the fruit is specified.
- The drying. Chamber pressure and time decide how much water leaves the piece. In a study on freeze-dried mango slices, drying at 25 Pa for 17 hours left 5.46% moisture, while 35 Pa for 13 hours left 7.13%. Across the dozens of batches in a container, one chamber running with a worn seal can produce a softer, darker batch.
- The people. A sample is often cut and checked by the most experienced staff. A container is cut by several shifts, and cut size drifts.
- Storage and packing. Product that waits in a warm warehouse, or is packed on a fast line where one seal in a hundred leaks, picks up moisture the sample never saw.
- The voyage. A sample flies in days. A container spends weeks at sea, where heat and condensation work on any weak pack. The pack controls that prevent this are in packaging and shelf life for freeze-dried pineapple.
Where this product may not suit you: if your brand needs the same colour and sweetness in every month of the year, freeze-dried pineapple from any single origin will vary with the season. You can narrow the variation with fruit specifications, but you should budget for either a wider colour tolerance or a smaller buying window.
What should the bulk contract lock from the approved sample?
The physical sample, the numbers that describe it and the tolerance around each number. A photograph and a signature on an email are not enough.
The reference sample should be sealed in at least three bags, signed and dated, with one kept by the buyer, one by the factory and one by the supplier’s QA. Record the fruit lot, the Brix of the fruit used and the drying batch. Photograph it under standard daylight lighting (D65), without filters, so colour can be compared later. Separately, each shipment can be preceded by a pre-shipment sample of 100–200 g in two sealed foil pouches with desiccant, sent by courier within 24–48 hours of packing, one for your sensory and rehydration check and one kept sealed for your laboratory, and FruitBuys retains a sample of every container lot at 22 ± 2 °C for the full shelf life of the lot, up to 24 months, as the reference for any complaint.
Then write the tolerances. These are the values FruitBuys works to for freeze-dried pineapple chunks:
| Attribute | Reference value | Tolerance for bulk | How it is measured |
|---|---|---|---|
| Chunk size | 12 mm | 12 ± 2 mm, at least 90% within 10–14 mm | Caliper or sieve, stated sample size |
| Moisture | 3.5% | 3–5% | Vacuum-oven method for dried fruit |
| Water activity | 0.22 | ≤0.30 | ISO 18787 |
| Colour | L* 65 | L* 62–68; colour difference ΔE below 3 | Colorimeter against retained sample |
| Texture | 4 N | Below 5 N | Texture analyser, stated probe |
| Fresh fruit Brix | 16° | 15–17° | Refractometer at receiving |
| Foreign material | None | None | Metal detection on 100% of product (Fe 1.5–2.0 mm, stainless steel 2.0–2.5 mm) |
ΔE is a single number for colour difference between two samples: the lower it is, the closer the match. Agree the instrument and lighting as well as the limit.
Fruit acceptance is part of the same contract. FruitBuys receives pineapple for retail-grade product at 15–17° Brix and rejects fruit below 12°. The limits for moisture, water activity and food safety belong in your freeze-dried pineapple specification; this table only covers how close bulk must stay to the sample.
We do not accept a purchase order for freeze-dried pineapple without signed tolerances. It protects both sides: the buyer has a basis to claim, and the supplier has a clear target to produce to.
How do you catch a drifting lot before it is loaded?
By checking during production, not only at the end. Sample approval opens supplier qualification; it does not close it.
The sequence FruitBuys runs for each order:
| Stage | What is checked | Action if it fails |
|---|---|---|
| Pilot run | 50 kg made from the fruit lots that will supply the container, not the sample farm | Buyer approves before the main run |
| 30% of production | Moisture on the first five bags | Above 5%: stop, re-dry, find the cause |
| 50% of production | Colour, size, seal quality | Adjust cutting or drying before continuing |
| Pre-shipment | Acceptance sampling at AQL 1.0 for major defects and 2.5 for minor; metal detection on all product; seal and vacuum check on every bulk bag | Hold the lot |
| Evidence pack | Photos of fruit, cutting, trays, packing, sealing, cartons and loading; a two-minute video of the line running your lot; lab results for the container lot, including ethephon | Released with the shipping documents |
AQL, the acceptable quality limit, is a sampling rule from ISO 2859-1: it sets how many cartons are opened and how many defects are allowed before a lot fails. A tighter AQL means fewer defects slip through; state it in the contract, because a looser default can pass a lot you would reject by eye.
How do you know the COA belongs to your lot?
Check four things on every certificate: the lot number matches the packing list and carton labels, each result sits next to your agreed limit, each test names a method inside the laboratory’s accreditation, and pathogen results state how many units were tested.
Four checks separate a lot certificate from a document that only looks like one. The lot code on the report matches the packing list and carton labels exactly. Each method sits inside the laboratory’s ISO/IEC 17025 scope for dried fruit (AOAC 934.06 for moisture, ISO 18787 for water activity, QuPPe for ethephon). The sampling is stated: how many units were drawn from the lot and whether they were composited. Each result carries its limit of quantification, not just the word “complies”.
A “typical analysis” sheet or a certificate from the sample batch describes other product; only results tied to the container lot count for acceptance. FruitBuys issues a lot COA from an ISO/IEC 17025 laboratory for every full container, covering moisture, water activity, total plate count, yeasts and moulds, E. coli and Salmonella, with ethephon added for EU-bound containers. Trial and LCL orders ship with the factory’s release QC report and the latest third-party baseline surveillance report; if your QA needs an independent test of a trial lot, it is arranged at net laboratory cost and credited back in full against your first full-container order.
The sampling behind a “not detected” result matters more than most buyers realise. With five 25 g units tested, the chance that a lot passes although some units are contaminated is:
| Share of 25 g units contaminated | Chance of passing with 5 units | Chance of passing with 10 units |
|---|---|---|
| 1% | 95% | 90% |
| 2% | 90% | 82% |
| 5% | 77% | 60% |
| 10% | 59% | 35% |
A clean certificate lowers the risk; it does not prove absence. That is why the supplier’s hygiene controls and results across many lots carry more weight than any single certificate, and why the number of units and how they were drawn must be written on the COA.
What if the container still does not match the sample?
Handle it as a measurement, in this order:
- Compare with the retained sample, not with memory. Open your sealed reference bag next to the delivered product.
- Measure against the signed tolerances. Colour, size, moisture, water activity, texture. Record numbers, not adjectives.
- Keep the evidence. Retain rejected product and photograph it next to the reference sample under the agreed lighting.
- Apply the contract. Outside tolerance, the supplier normally bears rework, replacement or credit. Inside tolerance but still unacceptable to you, the tolerance was too wide: tighten it for the next order rather than disputing this one.
The cost of skipping the tolerance table is easy to size: kilograms outside your expectations × your landed cost per kilogram, with no contractual claim. On a 3,000 kg container, a 5% fines or colour problem is 150 kg you pay for but cannot use.
Frequently asked questions
Why did my container arrive darker than the approved sample?
Usually lower-Brix fruit, a longer or hotter drying run, or moisture picked up in storage. A signed colour tolerance measured under agreed lighting tells you whether it is a claim.
Is a sample from the supplier’s best batch a fair reference?
Only if tolerances are written around it and a pilot run from the bulk fruit confirms it can be reproduced.
How long do I have to raise a quality claim?
FruitBuys’ standard window is 14 days from container unloading for packaging, appearance, breakage and water activity, and 30 days for laboratory results.
Does FruitBuys keep a sample of my lot?
Yes. A retained sample of every container lot is kept for its full shelf life, up to 24 months, so any later question can be checked against the lot itself.
Request a reference-sample review
Send your approved sample details, current specification and the attributes you care most about. FruitBuys will return a tolerance table and a production-check plan for your next order, so you can decide what to sign before production starts. You can also submit an RFQ for freeze-dried pineapple or browse the freeze-dried fruit category.
