Identify purposeful water additions
Start by asking where water is intended to go. Wash water contacts the outside of the fruit and then leaves as dirty water. Cleaning water circulates through a defined circuit and is not a food ingredient. Formulation water is added to the product on purpose and becomes part of its identity, mass and label declaration. These are different duties and should not share a single “water use” number.
If water is added to pulp or puree, record the addition point, the measured quantity and the reason. The product identity and any declared composition have to remain consistent with the standard or specification that applies in the destination market. The FAO-WHO Codex standards registry is an entry point for current product standards; a project should verify the named standard and its revision before quoting a composition limit. This article does not substitute a market-specific regulatory review.
Separate washing from formulation water
FAO’s general juice guidance warns that washing and water handling can either reduce contamination or make it worse if the water and equipment are not sanitary. Water dumping and transport can be a gentle way to move fruit, but the same guidance treats poorly treated dump water as a hazard. Spray and brush washing also need a defined supply, debris collection and drainage path that does not run into the next product stage.
In a multi-fruit plant, the washing boundary becomes more important because the next fruit may arrive with different soil, stems or surface material. Record the source and condition of wash water, whether it is recirculated, how debris is removed and where the discharge goes. Do not count wash water as product water, and do not assume that a drain or a CIP return can carry both streams without a defined route.
Track pulp, reject and wastewater streams
A useful water account starts with a defined boundary and a consistent unit. Record incoming fruit mass, any measured formulation water, qualified pulp, peel, stones, seeds, screening rejects, samples, spills and wastewater. Some water is already present in the fruit and some leaves with the rejects or during heating. A balance that only compares fruit input with pulp output will hide those streams and overstate the useful fraction.
Choose measurement points that operators can actually reach and repeat. A tank level, a scale, a flow meter and a batch record may each answer a different question. State whether a figure is a design estimate, a measured batch value or a calculated difference. When a stream cannot be measured, say so and keep it visible as an uncertainty rather than assigning it to “loss” or, worse, to product.
Compare batches without inflated recovery
If formulation water is added, the product-to-incoming ratio is not the same as fruit recovery. Added water can make the output mass look larger while the fruit-derived solids remain unchanged. Report the qualified pulp mass, the added mass and the calculation basis separately. Where no additions are present, an observed recovery ratio can still be useful, but it remains an observation from that batch rather than a guaranteed yield for another cultivar or season.
The same discipline applies when comparing fruits. A mango batch, a guava batch and a papaya batch may use different preparation, screening and water additions. Compare them on a stated product basis and with the relevant rejects, not on a single output number. A measured campaign record can help keep the raw observations together; it should not turn a user-entered classification into a quality or safety acceptance.
Keep the water account usable after start-up
Water accounting is not a one-off commissioning exercise. Assign the meters and records to named operating routines, check calibration and review the balance when a fruit, screen, cleaning chemical or package changes. Include water quality and drainage in the utilities review, and give wash-water, product and cleaning routes distinct identities on the layout.
A clear water account supports three practical decisions: whether a batch reconciliation is believable, whether a changeover has actually removed the previous product, and whether a utility claim in a quotation has a defined basis. It does not establish a yield guarantee, a regulatory compliant product or a validated cleaning result. Those require their own evidence.
Sources
These sources were reviewed for general principles and dated context. They do not certify a machine, a project configuration or a product specification.
- Principles and practices of small- and medium-scale fruit juice processing, Chapter 6: General juice manufacture principlesFAOWashing, water quality, extraction and mass-transfer principles. Historical guidance, not a project water balance.
- Codex texts and standards, official registryFAO-WHO Codex AlimentariusEntry point for current product identity standards. Verify the named standard and revision before using a composition limit.
Work through the line utilities checklist
Define wash-water, product, cleaning, drainage and metering interfaces before comparing equipment quotations.