Key points
- Define cloud as a product target before choosing a finishing step.
- Record mash, press and transfer conditions as one juice base.
- Compare samples under the storage conditions that matter.
Write the cloud target before the trial
Cloudy apple juice is not simply juice that has not been filtered. It has an intended suspended phase, a permitted coarse-material level and an appearance that the buyer expects to see in the package. Before a trial, write those expectations down: the reference sample, the viewing method, the container, the storage interval and the conditions under which the sample will be judged. Otherwise the trial produces opinions rather than a decision.
The target should distinguish the cloud the product needs from material that should be removed. A coarse screen may remove pulp and seed fragments while leaving the finer cloud. A clarification step may remove both. If the buyer has not defined the difference, the trial cannot decide which stream is correct. Start with a reference product and a written description, then choose the measurements that can test it.
Source for this section FAO general juice manufacture principles
Record the mash and press as one set of conditions
The trial record should begin with the fruit lot: cultivar, maturity, storage history and condition after sorting. Then record the crusher configuration, mash temperature and holding time, press type and operating cycle, juice screening and the delay between pressing and the next step. These variables change the solids that reach the finishing section, so a trial that reports only the final appearance cannot be repeated.
FAO's juice guidance describes crushing and pressing as a compromise between extraction and the carryover of skin, seed and other material. A more thorough comminution may increase yield while extracting components that affect colour and flavour. The point is not to find one universal setting. It is to record the setting actually used, so a later change can be separated from a change in fruit or finishing.
Source for this section FAO general juice manufacture principles
Build comparable samples from one juice base
A useful cloudy-juice trial splits one pressed juice base into samples rather than comparing juice from different days. Keep the fill volume, headspace, container type and initial temperature consistent. Include a control sample that receives the minimum handling, and duplicate the samples that matter. Record the order of filling and any hold time before treatment, because those details can change the oxygen history of the sample.
If the trial compares a finishing option, define what changes and what stays the same. A screen change, a centrifuge setting, a deaeration step and a thermal treatment are different variables. Testing them together can produce a product that looks acceptable but cannot be explained. A staged trial is slower, but it gives the project a result it can use in equipment selection and a later validation.
Source for this section FDA Juice HACCP guidance, FAO general juice manufacture principles
Store samples under the conditions you intend to compare
Cloud behaviour is a function of time and storage conditions. Record the storage temperature, light exposure, container and the interval at which samples are assessed. If the product will be distributed chilled, do not judge stability only from a sample left on a bench. If the package is translucent, include light exposure in the trial. The conditions should match the intended distribution route as closely as the trial allows.
Assessment should happen at planned intervals, not only when someone notices a problem. Record the observation method: visual score against the reference, photographs under stated lighting, sediment height or mass, and any instrumental measurement the project can support. A single end-point photograph is weak evidence. A series of observations under the same conditions shows whether the cloud is changing and when.
Source for this section FAO general juice manufacture principles
Read cloud, sediment and colour together
A cloudy product can fail in more than one way. It may settle quickly, form a dense sediment, develop a visible colour change or separate in a way the buyer rejects. Those outcomes should be recorded separately. A sample that keeps its cloud but browns is not equivalent to a sample that stays light but clears. The trial report should show the trade-off rather than collapse everything into a single acceptable verdict.
Taste and aroma belong in the same review, especially when a treatment step changes the volatile profile. Record the panel, the reference and the conditions. This is not a substitute for a trained sensory programme, but it prevents a visually acceptable sample from being promoted without anyone noting a flavour change. The result is a product brief with evidence behind it.
Source for this section FAO general juice manufacture principles
Make the report decision-ready
The trial report should identify the fruit lot, the process conditions, the sample plan, the storage conditions, the observations and the deviations. It should state what the trial supports and what it does not. A result from one cultivar and one storage condition does not establish a universal cloud treatment. It may, however, justify the next trial or a specific equipment discussion.
Close with the decision the project needs: repeat the trial, change the finishing step, test another package, or move to a validation plan with the chosen supplier. Link the result back to the route and the equipment duties so the reader can connect the trial to the line configuration. The value of the article is not a promised stability result; it is a record that makes the next question sharper.
Source for this section FDA Juice HACCP guidance, FAO general juice manufacture principles
Trial variables that must travel with the sample
The sample code is only useful when the conditions behind it are recorded.
Scroll the table sideways to compare every column.
| Trial area | Record | Why it matters |
|---|---|---|
| Fruit lot | Cultivar, maturity, storage, condition | Explains the starting cloud |
| Mash and press | Screen, temperature, cycle, transfer delay | Makes the juice base repeatable |
| Sample plan | Fill, headspace, control, duplicates | Separates treatment from handling |
| Storage | Temperature, light, container, intervals | Makes the comparison bounded |
| Assessment | Reference, method, sediment, colour, taste | Shows the trade-off |
Discuss a cloudy NFC line. Start with the product, the fruit condition and the records your project needs, then compare the equipment duty.
Sources
Primary and official references support the process background. They do not certify this site, a supplied machine or a validated plant process.
- FAO, Chapter 6: General Juice Manufacture PrinciplesAccessed 28 October 2026. Used for unit operations, receiving and sorting, extraction, pressing and juice-finishing context.
- FDA, Guidance for Industry: Juice HACCP Hazards and Controls Guidance, First EditionAccessed 28 October 2026. Used for the HACCP framework, record expectations, the 5-log pathogen reduction context and the patulin discussion.
Sources accessed 28 October 2026.