How a Sri Lankan Fruit Pulp Plant Evaluated a Multi-Line Fruit Peeling Solution

• First, production must take place within a strictly regulated cleanroom environment.
  Raw materials arrive in stackable plastic crates (approximately 10 kg each) via chilled trucks and are held in four separate chiller rooms, one per fruit. From there, electric pallet trucks transfer the crates to conveyors, and the fruit enters the cleanroom through a small wall opening fitted with an active air curtain. Air must leak outward for bio-security. The product itself is uncompromising: fresh pulp, no additives, no preservatives, frozen without any heat treatment — because cooking alters the flavour of tropical fruit — packed in 1 kg portions and quick-frozen to -20 °C for export.

• Second, the facility requires four entirely separate processing lines.
  Pineapple and papaya are available year-round in Sri Lanka, while mango and avocado are seasonal. Dedicated lines are essential to streamline operations and strictly eliminate any risk of cross-contamination — especially crucial for an unpasteurized product. Each fruit also has its own peeling and seed-handling requirements: pineapple must be peeled, cored and have its eyes removed “as far as practical”; papaya, mango and avocado all require seed handling, ideally without hand contact. After peeling, seeded fruits pass through a pulper with an integrated sieve so that seeds, leftover eyes and fibres are separated automatically, leaving a thick paste with no water added — only the fruit’s own juice.

• Third, the client faces a local regulatory constraint: the project must provide a certain number of jobs to gain approval.
  A semi-automatic line with manual loading is therefore preferred over a fully automated system — machines handle the repetitive peeling and pulping, while operators feed fruit, inspect output and handle packing. Throughput is fixed at 500 kg/hr across all four lines. The machinery must also accommodate significant natural size variation in the raw materials without time-consuming pre-sorting, and the entire electrical system must be compatible with the local 230/400 V, 3-phase, 50 Hz standard. CIP cleaning is required every four hours of operation. The customer supplied his own specification sheets for the peeler and the bubble washer and asked us to confirm compliance with every item.

• Cross-contamination between fruits.
  A single multi-purpose peeler would be cheaper, but switching between fruits means cleaning cycles between products and a real risk of carryover. For a plant selling to export buyers under the highest international standards, that risk is not acceptable. Dedicated machines cost more, but they remove the problem at the design stage.

• Pineapple eyes versus flesh yield.
  This was the customer’s sharpest point, put better than most buyers ever manage: if the machine cuts too deep, the best-flavoured outer layer goes into the bin. Fully automatic eye removal always costs flesh – no machine removes every eye with zero damage. The real decision is between a fast automatic pass with higher fruit loss and a lighter peel with a manual touch-up that preserves yield.

• Seed removal without hand contact.
  Once the skin is off, the fruit is exposed, and every hand touch is a contamination risk in a clean room. Papaya seeds in particular cling to the flesh, so hand deseeding was ruled out by the customer himself – which pushed us toward the pulper with an integrated sieve.

• A new product category with no local benchmark.
  Frozen fruit pulp for export is new to Sri Lanka, with no neighbouring plant to copy, so every machine has to be justified on paper – specifications, test videos, references – before purchase. The customer checked our track record directly, asking whether we had supplied a complete line of this kind anywhere.

• Seasonal raw material.
  Pineapple and papaya run all year, but mango and avocado are seasonal. Machines on those lines sit idle part of the year, so the selection must balance utilisation against labour costs, and the machines must tolerate proper shutdown and storage between seasons.

• Bubble cleaning machine with conveyor feed.
  Fruit leaves the cold rooms and is washed to remove soil and surface residues. The washer length is selected by capacity – for 500 kg/hr we sized a unit with a matching conveyor section so crates can be tipped straight onto the belt. An air-blow drying section is integrated at the discharge end: freshly washed fruit carries a lot of surface water, which makes peeling messy and adds load downstream, so a short drying run removes surface moisture before the fruit reaches the peeler.

Dedicated peeling machines, one per fruit:

• Pineapple. A pineapple peeling and coring machine removes the outer skin and the central core. For the eyes we offered two options: a lighter single-layer peel plus a quick manual trim (minimal flesh loss, some labour), or a double-layer peel that removes the eyes automatically with higher yield loss. Given his emphasis on maximum yield, we recommended the first, with the pulper’s sieve catching remaining eye fragments.
• Papaya. A dedicated machine that peels and halves the fruit. Seeds are separated in the pulper, so no hand deseeding is needed.
• Mango. A mango peeler machine with automatic size adaptation, demonstrated in a test video with large and small mangoes.
• Avocado. A separate dedicated machine that halves the fruit after peeling so the pit drops out on its own. It does not remove the pit; we confirmed this limitation up front.

• Pulper with integrated sieve.
  For papaya, mango and avocado, the peeled and halved fruit goes into a pulper that separates seeds, leftover eyes and fibres, producing a thick paste with no added water. The same machine doubles as a safety net for small pineapple eyes.