How Is Freeze-Dried Mango Made, and What Should Your Auditor Check at Each Step?

Freeze-dried mango is made in eight steps: fruit intake, washing and cutting, deep freezing, a 20–24 hour vacuum drying cycle, sorting, a dry-room pack, metal detection and release testing. Each step has one control that decides what arrives at your dock: ripeness at intake, cut size, freezing temperature, final moisture, fines, room humidity, foreign-body rejection and the lot COA. This guide walks an auditor through a FruitBuys partner facility step by step, with what to look at and what to ask for, so your first visit or remote audit covers what matters.

The process at a glance

Step 1: Which mango goes in?

Ripe fruit of one cultivar, checked for sugar before it is cut. The standard is Keo, a firm mango at 14–16 °Brix that cuts clean cubes and holds its shape through drying. Cát Chu runs sweeter at 14–18 °Brix and is chosen for snack slices; once ripe it has to be processed within about 24–48 hours, so intake is scheduled around it. Off-season fruit from September to November is noticeably more tart, and FruitBuys tells buyers which harvest their lot comes from.

What it means for you: ripeness at intake sets the flavour and colour of every bag in the lot. Ask to see the intake log for a recent batch: Brix readings, cultivar and orchard source on one sheet.

Step 2: How is the fruit cleaned and cut?

Washed, sanitised, peeled and cut in a hygiene-zoned area. The fruit is washed and sanitised before the knife touches the flesh, so the outside of the peel never contaminates the cut surface. Cuts are set by format: slices 6–7 mm thick, cubes 5–10 mm, bites 10–15 mm and granules 2–5 mm, with slice tolerance ±0.5 mm.

What it means for you: cut size decides how a piece dries, how much breaks in your mixer and how it looks in the pouch. Slices thinner than 5 mm break heavily in mixing, which is why the slice standard sits at 6–7 mm. Ask how cut size is checked during the shift, and look for the gauge at the cutting station.

Step 3: Why freeze so deep?

To lock the fruit’s structure in place before any water leaves. Cut fruit goes onto trays and into a blast freezer at −35 to −40 °C. Fast, deep freezing forms small ice crystals, so when the ice is later removed the piece keeps its shape, colour and a fine, crisp structure instead of collapsing.

What it means for you: a piece that was frozen too slowly or allowed to soften before drying comes out shrunken and tough. Ask for the freezer temperature log covering the batches in your order.

Step 4: What happens inside the freeze dryer?

The ice turns straight to vapour under deep vacuum, then the last bound water is driven off. Frozen trays go into a vacuum chamber. Pressure drops below 100 Pa and gentle heat is added to the shelves, so the ice sublimes, passing from solid to vapour without melting, and freezes out on a condenser at about −45 °C. Primary drying takes 14–16 hours; secondary drying another 4–6 hours takes the moisture down to the release target. The full cycle runs 20–24 hours, with production chambers handling about 1,000 kg of fresh fruit per batch.

That long cycle is where most of the energy goes, about 8–12 kWh per kilogram of finished product. It is also why freeze-dried mango costs more than hot-air dried fruit, and why a supplier who shortens the cycle to save cost usually ships softer mango. Pushing moisture from 5% down to 3% adds roughly 3–4 hours of secondary drying and about 2% more fruit per kilogram.

What it means for you: the cycle record is the single best document for judging a freeze-dried supplier. FruitBuys shares the batch cycle record for your production lot, showing chamber pressure, shelf heating curve and cycle duration, on QA request as part of the technical release dossier.

Step 5: How is a batch checked when it comes out?

Trays are unloaded, the batch is mixed, fines are sieved out and moisture is checked. Pieces from the top, middle and bottom of the chamber dry at slightly different rates, so trays are combined before packing to give the lot one even moisture. Pieces are then sorted: broken pieces and fines below 2 mm come out. Sorting losses run about 8–10% for slices, 3–5% for cubes and close to zero for powder, which is milled from the same pieces.

What it means for you: a lot is only as even as its mixing. Ask to see moisture and water activity measured on the same sample, because one without the other hides the risk of mango that leaves crisp and arrives soft.

Step 6: Why does the packing room matter so much?

Because Vietnam’s air holds about 80% humidity, and freeze-dried mango pulls moisture back within minutes. Packing takes place in a closed room held below 35% RH at 20–22 °C. Each 5 kg foil bag is filled, gently vacuumed so it sits flat without crushing the pieces, given a food-grade desiccant sachet, and heat-sealed. No nitrogen is used: a flat, gently vacuumed bag holds pieces still at sea and keeps cartons compact.

Two small details show whether a packing room is run well: a long-neck funnel that keeps mango dust off the seal area, and staff who wipe the bag mouth before sealing, because dust in the seal is the most common cause of a slow leak. Bags are handled flat, since a hard fold can crack the aluminium layer.

What it means for you: stand in the packing room and look at the hygrometer. If it reads above 35% RH, the crunch you approved will not survive the voyage. Ask for the room’s humidity log for the shift your lot was packed.

Step 7: How are foreign bodies controlled?

Every carton passes a metal detector set to Fe 1.5 mm, non-Fe 2.0 mm and stainless steel 2.5 mm. As standard practice, the detector is checked with test pieces at the start of the shift, at intervals and at the end, and product packed since the last good check is held if a check fails. Facilities supplying FruitBuys use metal detection rather than X-ray, so the controls upstream matter too: blade checks at the cutting station, sieve screens intact, and glass and hard-plastic policies in force.

What it means for you: ask for one shift’s metal detector check sheet and the procedure for what happens to product after a failed check.

Step 8: What has to pass before a lot ships?

Moisture 3–5% and water activity ≤0.30, plus microbiology on a third-party lot COA. Every full container is released on a COA from an independent ISO/IEC 17025 accredited laboratory covering moisture, water activity, total plate count (≤10,000 CFU/g), yeasts and moulds (≤100 CFU/g), E. coli (<10 CFU/g) and Salmonella (not detected in 25 g). Lead, arsenic and aflatoxins are covered by periodic baseline testing. A pre-shipment sample of 200–300 g, in two sealed pouches from the packed lot, is couriered to you within 24–48 hours before stuffing, and a retained sample is kept for the full shelf life.

When the container is loaded, cartons are floor-stacked and protected against condensation with calcium chloride desiccant poles along the walls and a carton or kraft cover over the top layer, which matters on routes where containers sit in the rain or cross hot ports.

What it means for you: release is a document trail, not a promise. The lot code on the COA, the pre-shipment sample and the carton labels should all match.

How does FruitBuys keep this consistent across orders?

One qualified facility per contract, one specification and open audit access. FruitBuys coordinates the orchard regions, locks one qualified processing facility to each contract and sets the process standard above. Any change of facility needs written notice and a fresh pre-shipment sample approval. Facility certifications cover HACCP, ISO 22000, US FDA Facility Registration and BRC (qualified processing facility) (Halal certification available on request), with certificates in your technical file before signing. Your QA team can audit on site or remotely.

The checks above turn into contract clauses, with the approved sample as the bulk reference, in the RFQ and sample approval checklist; release values and testing are covered in the moisture and QA guide.

When is a site visit not the best first step?

When you have not yet tasted the product. An audit confirms that a facility can repeat a product; it cannot tell you whether that product fits your line. Start with a sample in 3–5 working days, run it through your process, and plan the audit once the specification is agreed. Audits are best planned around a production week, so your team sees the cycle running, not an empty room.

Arrange a sample or an audit

Tell FruitBuys your application and whether you want an on-site or remote audit. We send freeze-dried mango from stock in 3–5 working days and agree with your QA team which records to review before a visit. Specifications are on the freeze-dried mango product page; the wider programme is in the freeze-dried mango supplier guide.

CONTACT FRUITBUYS

[email protected] · WhatsApp Export +84 919 739 589

FAQ

How long does it take to freeze-dry mango?

About 20–24 hours in the dryer: 14–16 hours of primary drying and 4–6 hours of secondary drying, after freezing at −35 to −40 °C.

What temperature is mango frozen at before freeze-drying?

−35 to −40 °C, fast enough to form small ice crystals and keep the piece’s structure.

Why is freeze-dried mango packed in a dry room?

Because it absorbs moisture from humid air within minutes. Packing below 35% RH keeps it crisp through the voyage.

Do freeze-dried mango suppliers use X-ray?

Facilities supplying FruitBuys use metal detection set to Fe 1.5 mm, non-Fe 2.0 mm and stainless 2.5 mm, with upstream controls on blades, sieves and glass.

Can we audit the facility?

Yes. FruitBuys locks one qualified facility to each contract with audit access for your QA team, on site or remote.