How to Set Up an Industrial Raisin Processing Line: A Producer's Technical Guide

If you produce raisins at industrial scale, there comes a point where sun-drying and hand-destemming stop being financially viable. Mechanical processing is what separates producers selling cheap bulk from those exporting to premium markets with traceable, certified product.

This guide is for you: the producer in Mendoza, San Juan, California, or any other raisin-growing region considering mechanizing your processing. We’ll walk through the two critical stages, the six line configurations Albion manufactures, how the architecture changes between boutique and industrial scale, how to size equipment based on annual volume, and when it makes sense to add optical sorting for export.

Why mechanize processing?

Four concrete reasons that justify the investment:

1. Time and labor. Manually destemming one ton of raisins takes 8–10 person-hours. An Albion 600 kg/h line does the same job in under 2 hours with a single operator monitoring.
2. Uniform quality. A vibrating screen, a conical destemmer, or a centrifuge always produce the same result. Hand-sorting depends on the (tired) eye of the operator.
3. Access to premium markets. European, Russian, and Middle Eastern buyers require washed, sized, and food-safety-audited product. Without an industrial line, that market is out of reach.
4. Scalability. A well-dimensioned line accompanies your growth: the same warehouse, the same services, and one additional module are enough to double capacity.

The two industrial processing stages

After harvest and sun-drying (the most common method in Argentina), raisins enter the plant as dried clusters. From there, two main processes need to be mechanized:

Stage 1 — Destemming (D line)

Separates the loose raisin from the rachis (the cluster’s “skeleton”) and cleans the product:

• Receives raisins in clusters from the drying field.
• Returns loose raisins, free of stems and leaves, classified into commercial sizes.

It’s the mandatory first step if you receive raisins harvested and dried as clusters (which is how 90% of Argentine producers operate).

Stage 2 — Washing and finishing (L line)

Washes the loose raisin, dries it with controlled moisture, and prepares it for packing:

• Receives already-destemmed raisin (can come from your own D line or another process).
• Returns washed, dewatered raisin with ideal moisture and optionally brightened and weighed in exact batches.

It’s the step that transforms standard raisin into premium export product. If your market is buyers who pay more, this line is what differentiates you.

The six available configurations

Albion manufactures both stages in three sizes each — six configurations total. But the difference between them isn’t just capacity: the process architecture also changes. Boutique versions are compact (fewer modules), and as scale grows, stages are added that improve quality and automation.

Model	Stage	Capacity	Stages in flow	Ideal for
PUA 300 L	Washing	250–300 kg/h	4	Boutique processors, artisan brands, niche exporters
PUA 300 D	Destemming	250–300 kg/h	4	Same profile — producers just starting to mechanize
PUB 600 L	Washing	550–600 kg/h	9	Mid-scale processors with export markets
PUB 600 D	Destemming	550–600 kg/h	9	Same profile — delivers 3 sizes at output
PUA 2000 L	Washing	1,800–1,900 kg/h	11	Industrial high-volume plants
PUA 2000 D	Destemming	1,800–1,900 kg/h	9	Dual destemmers in series + maximum efficiency

💡 The naming is transparent: the first two letters (PU) stand for Pasas de Uva (raisins), the third (A or B) is the mechanical family, the number is nominal capacity, and the final letter (L or D) is the process type.

Destemming: how the process changes across the three sizes

PUA 300 D — the compact 4-module solution

For boutique producers, Albion concentrates the industrial destemming logic into just four modules, vertically arranged to save space:

1. Dosing feeder with cluster decompacter: regulates intake at 300 kg/h and starts breaking up compact clusters.
2. Conical destemmer: the heart — the same refiner used in the larger lines, with inner rubber paddles and grooved rubber-lined walls, height-adjustable for different raisin types.
3. Aspirator: extracts stems, leaves, and light residues.
4. Vibrating sizing screen: positioned below the destemmer and aspirator, leveraging gravity and cutting total space in half. Classifies clean raisins into commercial calibers.

This vertical layout is what allows the PUA 300 D to fit in any boutique warehouse without sacrificing destemming quality.

PUB 600 D — full industrial flow at mid-scale

At 600 kg/h, the process unfolds across 9 stages in continuous flow:

1. Hydraulic Bin Tipper with independent power unit.
2. Dosing feeder — inclined belt with metering rake and damper. Integrated cluster decompacter.
3. Two-level vibrating screen that separates loose raisins from pedicels.
4. Vacuum aspirator with automatic waste discharge via motorized rotary valve.
5. Elevator to the next stage.
6. Conical destemmer with screen — the same premium refiner as the PUA 2000.
7. Final vacuum aspirator to ensure purity.
8. Elevator to sizing.
9. Sizing screen that classifies into 3 commercial calibers at the output.

Those intermediate elevators and dual aspiration are what differentiate it from the compact version. The PUB 600 D delivers three calibers ready for different markets from a single line.

PUA 2000 D — dual destemmer in series

At 2,000 kg/h, the architecture maintains the industrial flow but incorporates a second conical destemmer in series with an intermediate aspirator between them. That’s the unique difference: it combines industrial volume with premium destemming rate. The rest of the process (two-level screen, aspirators, sizing) scales in dimensions to 1,800–1,900 kg/h.

Washing and finishing: three levels of detail by scale

PUA 300 L — four essential modules

For boutique scale, Albion delivers what’s needed for premium finishing in just four modules:

1. Cascade washer: recirculating water bath that removes impurities and conditions the raisin.
2. Rinsing and dewatering vibrator: clean-water shower for final rinse + recovery of excess.
3. Illuminated inspection conveyor: final visual control with high-intensity lighting.
4. Elevator with brightener: transports the raisin upward while a dosing pump applies brightening oil in exact proportion.

No hydraulic bin tipper, no pre-washer, no centrifuge, no automatic weighing: what’s needed for premium product in a reduced footprint.

PUB 600 L — full industrial flow with automatic weighing

At mid-scale, the process adds 5 more stages to reach 9:

1. Hydraulic Bin Tipper.
2. Dosing Feeder.
3. Rotary Pre-Washer (stainless cylinder with water rain for initial cleaning).
4. Cascade Washer (deep bath with recirculating water).
5. Rinsing and Dewatering Vibrator.
6. Centrifuge that removes surface water and leaves ideal moisture.
7. Illuminated Inspection Conveyor.
8. Elevator with Brightener: applies oil in exact proportion while elevating.
9. Automatic Weighing: dispenses in exact batches via load cell + touch screen.

This is where moisture control by centrifuge, dedicated pre-washer, and separate automatic weighing come in — the three quality leaps that take the product to premium export standard.

PUA 2000 L — eleven stages with full inspection coverage

At industrial scale, the washing and finishing line adds three modules that automate stages still manual at mid-scale:

1. Hydraulic Bin Tipper.
2. Dosing Feeder.
3. Rotary Pre-Washer.
4. Double Cascade Washer (Double Riffle Platform — two water drops).
5. Rinsing and Dewatering Vibrator.
6. Centrifuge.
7. Spacing Vibrator: evenly distributes the raisin across the conveyor width before inspection, preventing clusters that hinder visual control.
8. Illuminated Inspection Conveyor with side discard boxes.
9. Collection Conveyor: captures the inspected product and concentrates it for the next stage.
10. Brightening Elevator with Automatic Weighing: combines auger brightening and precise weighing in a single module.
11. Transfer Conveyor: delivers weighed batches directly to the packaging area, synchronized with the brightener cadence to keep continuous flow unbroken.

The three extra stages (spacer, collection conveyor, transfer conveyor) are what differentiate a fully automated industrial process from a semi-automated one: they distribute load, synchronize flow, and eliminate manual interventions that are acceptable at smaller scale.

How to size your line based on annual volume

The most common question we get is: “What model do I need if I process X tons per year?”. The answer depends on how many hours you operate the line per day and how many days per year it’s in use.

The calculation

Annual capacity = hourly capacity × hours/day × days/year

Typical assumptions:

• Standard operation: 8 hours/day × 200 working days/year = 1,600 hours/year
• Intensive operation (extended shifts during harvest): 10 hours/day × 250 days/year = 2,500 hours/year

Raisins have strong seasonality in Argentina — harvest is concentrated in March-April and processing typically runs from May through September. If your line only runs in that window, adjust working days to the actual period.

Reference table (standard operation 8 hrs × 200 days)

Annual volume	Equivalent kg/h	Recommended model
Up to 480 tons	Up to 300 kg/h	PUA 300 D / PUA 300 L
480 - 960 tons	300 - 600 kg/h	PUB 600 D / PUB 600 L
Over 960 tons	Over 600 kg/h	PUA 2000 D / PUA 2000 L

⚠ Important: these ranges are orientative. If your harvest has short peaks and you need to process the entire annual volume in a few weeks, oversize: a PUB 600 working 4 hours per day for 60 days processes 144 tons — the same as a PUA 300 working 9 hours per day for 60 days, but with fewer shifts and less equipment wear.

Example case

A Mendoza producer with a 40-hectare own vineyard yielding about 4,500 kg of raisins per hectare processes approximately 180 tons per year. With standard operation (8 hrs × 200 days = 1,600 hrs), they need a line of:

180,000 kg ÷ 1,600 hours = 113 kg/h average.

→ A PUA 300 (250–300 kg/h) is more than enough and lets them process the annual volume in roughly 600 hours, leaving margin for growth and concentrated campaigns.

When to add optical sorting (Visys)

After washing and before packing, the line can integrate a Visys optical sorter. It’s the Belgian brand Albion represents in Argentina, and integrates natively into the L line.

Why add it?

• On washing lines, Visys detects stones and mineral matter that raisins carry over from sun-drying — the most recurring physical contaminant and the one that generates most claims in premium raisins.
• It also detects visual defects (color, stains, damage) with high-resolution RGB cameras.
• Advanced models add X-rays (VIREX) and hyperspectral scanning (AURA), which detect contaminants invisible to the human eye.

When does the investment make sense?

• If you export to Europe, Russia, the Middle East, or the US — premium buyers demand contaminant-detection auditing.
• If your brand has had quality complaints and you want to close that loop with an automatic filter.
• If your volume justifies the amortization (typically PUB 600 or PUA 2000 lines).

In boutique operations (PUA 300), Visys is integrated less frequently due to investment-to-volume ratio. But the architecture is ready to add it at any time.

Investment is scalable: you don’t buy a line, you buy an architecture

What most differentiates Albion from imported Chinese or European options is this: the three line families (PUA 300 / PUB 600 / PUA 2000) share sanitary architecture and construction philosophy.

That means:

• AISI 304 stainless steel with sanitary polish in product-contact zones — both in the boutique and the industrial line.
• Oil-bath gearmotors and shielded three-phase motors — the same in all three sizes.
• Sanitary white plastic modular belts — same food-grade standard.
• Pre-assembly and concatenation in our workshop before dispatch — the line arrives ready to position in your plant.
• 12-month warranty on mechanical parts of our manufacture.

What does this mean for your long-term investment?

If you start with a PUA 300 (because today’s volume justifies it) and in 3 years your harvest doubles, migration to a PUB 600 is by scaling, not full replacement. You preserve:

• The civil works of your warehouse (foundations, drainage, electrical installation).
• Plant services (water, energy).
• Several auxiliary modules (bin tippers, transport conveyors, control systems).

You swap the central process modules for ones sized to the new volume, and add the stages that the larger scale justifies (centrifuge, dedicated pre-washer, automatic weighing). This protects your initial investment and drastically reduces the total cost of growing capacity.

Next step

Every plant has its own reality. The ideal line depends on your volume, available warehouse, current services, and target market mix (local bulk vs premium export). The logical next step is:

1. Send us your operation’s basic data: estimated annual volume, target market (local / export), available services (kVA, water m³/h), warehouse dimensions.
2. Get a sized proposal: line built to measure with the modules your case justifies, budget, and timeline.
3. Review financing options linked to Banco Nación credit lines if applicable.

Visit our Raisin Lines page for photos and technical specs of the six models, or contact us to start your quotation.