Plant capacity: size it from the growing area and the season, not the machines

AgrifoodV · Published 19 October 2026

The question “how many tonnes per hour should the plant be” is often answered from an equipment supplier’s catalogue: a 5, 10 or 15 tonne-per-hour line, with an attractive data sheet. That is asking the question backwards. For fruit and vegetables, the real capacity of a plant is set by two numbers: how much fruit of processing grade can be brought in each day, and how many days a year fruit is available. After the design brief and the product specifications, this third article of the journey shows how to work out capacity from the raw-material growing area, and only then compare that figure with the capacity range of the equipment.

Why a fruit processing plant should not be sized from the machines

In the chapter “Design of Food Processes and Food Processing Plants” of the Handbook of Food Processing Equipment (2002), G.D. Saravacos and A.E. Kostaropoulos list the features that set food plants apart from other industrial plants. Three of them bear directly on capacity. In many plants, large quantities of sensitive raw materials must be processed in the shortest possible period; with seasonal crops, the equipment must withstand sudden extreme processing conditions. Fruit and vegetable processing is often seasonal. And because most seasonal raw materials are perishable, the company must provide relatively short-term cash flow to buy them.

On the economics, the same chapter states that the major part of the operating cost of food processing plants (60–80%) is raw materials and packaging materials; labour, energy and depreciation account for about 10% each. Two examples in the book lead to the same conclusion. In an apple juice concentrate plant, raw material represents 60–65% of total cost, and the availability of raw material and the apple variety have an important effect on process economics. In a citrus plant, raw material accounts for about 70% of product cost, and profitability depends strongly on the price of fruit.

The break-even diagram matters even more. At low production rates, fixed costs such as depreciation and maintenance stay constant, so total income falls below total cost. In the generalised diagram cited in the book, the break-even point is at about 50% of maximum capacity and the optimum operating point at about 80%. A line bought from an equipment catalogue but supplied with fruit for less than half its capacity falls below the break-even point of that diagram, however good the machines are.

Working back from the growing area: a worked example

The medium-sized orange plant in Saravacos and Kostaropoulos processes 20 tonnes of fruit per hour, running continuously 24 hours a day, 25 days a month, 4 months a year, i.e. 2,400 hours a year. Taking this operating regime as a reference, and using the Department of Crop Production and Plant Protection figures for passion fruit in 2024 (8,600 ha harvested, average yield 18.91 t/ha, output 163,400 tonnes), the minimum fruit volume and area for each line size are:

For pineapple, according to the Ministry of Agriculture and Environment, Vietnam has about 48,000 ha harvested, an average yield of 18.41 t/ha and output of more than 860,000 tonnes a year. A 12 t/h line on the same operating regime needs about 1,564 ha of harvested pineapple, or about 3.3% of national pineapple output. At the same capacity, passion fruit demands a much larger share of national supply. That supply is also concentrated in one region: the Central Highlands accounted for 86.4% of passion fruit area and 92.5% of output in 2024.

These figures are a floor, not a sufficient level. The calculation assumes the plant can buy the entire output of that area, whereas according to the National Agricultural Extension Centre, about 80% of passion fruit output goes to export, including fresh fruit. The plant therefore competes with the fresh channel for fruit. The share of fruit meeting processing grade, the share going to the fresh market and the monthly harvest calendar of each area must be surveyed by the investor, because published sources do not yet give figures for these indicators. Article 4 of the journey covers how to build a growing-area profile.

Reading capacity on equipment proposals

In three fruit juice line proposals for projects in Vietnam in 2025 reviewed by AgrifoodV, capacity ranged from 3 to 12 tonnes of fresh fruit per hour. Two details in proposals of this kind deserve a careful read by investors.

• Rated capacity changes with the fruit. One multi-fruit line configuration with aroma recovery is rated at “up to” 12 t/h for passion fruit, but only 6.5 t/h for pineapple, 3.5 t/h for papaya and 3.2 t/h for guava. The headline figure on the cover is usually the figure for the easiest fruit to process. If the actual growing area is pineapple, the capacity to compare is 6.5 t/h, not 12 t/h.
• Capacity is guaranteed with a tolerance. The proposals state that the capacity of each machine is guaranteed with a margin of tolerance, because agricultural raw material varies with season, variety and ripeness.

On equipment sizing, the chapter “Design and Selection of Food Processing Equipment” of the same handbook states that sizing is based on material and energy balances around each process unit. An oversizing of 10–20% is normally used to cover production problems such as the breakdown of a critical unit, and to meet production peaks. The book adds that if greater flexibility is desired, two smaller units are better than one large unit; splitting the capacity of process and utility units can give steadier, more flexible operation and lower maintenance cost. The right order is therefore: the growing area gives the required capacity, and only then are 10–20% added to arrive at equipment capacity. Not the reverse, taking an equipment capacity and then looking for a growing area.

Extending the operating season and keeping headroom for the harvest peak

In the chapter “Process Specification” of the Handbook of Food Factory Design (2013), D.L. Pyle notes that very few factories make only one product all year, because different raw materials are available at different times of the year. Saravacos and Kostaropoulos also note that the same facility may be used for different food products. Among the line proposals mentioned above is a configuration sharing one line for passion fruit, pineapple and avocado.

For the investor, the number of months with fruit is the key variable in the calculation in the previous section. The example in the book runs only 4 months a year. Adding a fruit with an offset season adds operating hours for the same investment in equipment, buildings and utilities, moving the plant further from the break-even point. The price is a cleaning cycle at each product changeover and a need for flexible equipment: Saravacos and Kostaropoulos stress that durability, flexibility and standardised spare parts are especially important in seasonal processing, when equipment runs continuously for a relatively short time and must switch from one product to another.

Pyle also points to the role of intermediate storage tanks: they decouple the stages so that each can run with its own cycle time and batch size, bringing the time efficiency of a multiproduct campaign close to that of a single-product campaign. When sizing for the harvest peak, one point is often forgotten: according to Saravacos and Kostaropoulos, when a plant is expanded, packaging machines and storage facilities typically become the bottleneck. This is also why P.J. Wallin, in the chapter “Design Principles” of the Handbook of Food Factory Design, places the question “how much storage is required for raw materials, packaging, and semi-finished and finished products” among the questions to answer before drawing the layout.

Market demand is already sending a clear signal. According to the Directorate-General for Agriculture and Rural Development of the European Commission, EU imports from Vietnam of preparations of fruit, nuts and vegetables (HS chapter 20, including fruit juices) rose from EUR 60 million in 2021 to EUR 214 million in 2025, up 65.4% from 2024 to 2025 alone. But buyer demand only answers the question “can we sell it”. The question “how many hours can we run” is still answered in the growing area.

What companies should do

AgrifoodV recommendations:

• Calculate capacity in the right order: harvested area, yield, share of processing-grade fruit, share going to the fresh channel, monthly harvest calendar, and only then tonnes per hour. Request equipment quotations only after this step.
• Draw up a monthly table of operating hours for each fruit. If total operating hours are low, consider adding a fruit with an offset season, or reducing capacity, rather than buying a large line and leaving it waiting for fruit.
• When comparing quotations, ask for guaranteed capacity for the fruit of your own growing area, not the “up to” figure for the easiest fruit.
• Add 10–20% capacity headroom for harvest peaks and breakdowns; consider splitting capacity into two smaller units; size the space for raw material, packaging and finished goods storage for the harvest peak, not the annual average.

AgrifoodV supports companies in developing the design brief, calculating capacity from the raw-material growing area and setting the design direction for processing plants.

References

1. Saravacos, G.D. and Kostaropoulos, A.E. “Design of Food Processes and Food Processing Plants”, chapter 1 in Handbook of Food Processing Equipment. Kluwer Academic/Plenum Publishers, New York, 2002, pp. 1–46 (pp. 13, 27–28, 30–31, 37–38 used).
2. Saravacos, G.D. and Kostaropoulos, A.E. “Design and Selection of Food Processing Equipment”, chapter 2 in Handbook of Food Processing Equipment. Kluwer Academic/Plenum Publishers, New York, 2002 (p. 48, section II “Sizing and Costing of Equipment”, and pp. 60–61 used).
3. Pyle, D.L. “Process Specification”, chapter 2 in Baker, C.G.J. (ed.), Handbook of Food Factory Design. Springer Science+Business Media New York, 2013 (pp. 13, 20–21 used). DOI: 10.1007/978-1-4614-7450-0_2.
4. Wallin, P.J. “Design Principles”, chapter 12 in Baker, C.G.J. (ed.), Handbook of Food Factory Design. Springer Science+Business Media New York, 2013 (pp. 298–303, sections 12.2–12.2.1 used). DOI: 10.1007/978-1-4614-7450-0_12.
5. Department of Crop Production and Plant Protection, passion fruit data for 2024 (area, yield, output; export share according to the National Agricultural Extension Centre), cited in Nhan Dan newspaper, “Phát triển bền vững cây chanh leo” [Sustainable development of passion fruit], 18 September 2025. nhandan.vn.
6. Department of Crop Production and Plant Protection, regional shares of passion fruit in 2024, cited in VnEconomy, 13 December 2025. vneconomy.vn.
7. Ministry of Agriculture and Environment, pineapple sector data, via the Government Online Newspaper, republished on antidumping.vn on 8 August 2025. antidumping.vn.
8. Directorate-General for Agriculture and Rural Development (DG AGRI), European Commission. Agri-food trade statistical factsheet: European Union – Vietnam, data extracted 17 April 2026. agriculture.ec.europa.eu.
9. Project materials reviewed by AgrifoodV: three fruit juice line proposals for projects in Vietnam in 2025 and one order confirmation for a multi-fruit line. Only configurations and capacity ranges are used; customer names, supplier names and prices are not disclosed.

Article by AgrifoodV, compiled and interpreted from the sources above (accessed 17–19 October 2026). This content is not a substitute for design advice or legal advice for any specific project. Cover image: Magda Ehlers / Pexels.

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