Packhouse practices for strawberry

When the strawberries arrive (from the field), unloading should begin immediately in order not to delay the further processing and the start of cooling. A first quality control can take place simultaneously with unloading. Further processing should also begin immediately (on a first-come first-served basis).

Strawberries are highly sensitive to compression and vibration damage and very susceptible to water loss. The packaging must provide physical protection to these fruits. For this purpsose, punnets (primary packaging) are often used which are placed in cartons or crates. The bottom of the punnets can be padded with bubble wrap to minimize vibrational damages. Never use force! Not when filling the punnet or when placing the punnets in the carton.

Filled packages must be stacked on a pallet and labelled with information including packhouse code, size/class, batch number, country of origin, and grower. Further the name of the fruit (strawberry) + variety, and net weight must be on each box label. The exact requirements can differ depending on local regulations and client demands. The completed pallets must be strapped well in such a way that the packaging cannot shift or fall. Often cardboard edge protectors are used to stabilize pallets. As soon as pallets are completed, they need to be moved to the cold storage.

A fast temperature reduction by means of forced air cooling is necessary to remove field heat as quickly as possible. Strawberry is not sensitive to chilling temperatures and should be stored as cold as possible without freezing. This means a rapid reduction of the temperature (via forced air cooling) to 1°C or further down to 0 °C. During this pre-cooling process, the fruit temperature should be checked regularly in the interior of the boxes, at the coldest and warmest spot of the pallet.

The storage time should be kept to a minimum, as strawberries are highly perishable. They can be stored for up to 1 week, but suboptimal temperature and disease pressure can significantly reduce this period. Check the quality in the storage room regularly. Strawberries should not be cooled to temperatures lower than 0.0 °C to prevent damage. That is why it is important to regularly check also the fruit temperature. A relative humidity of 90-95% can further help to preserve quality. Controlled Atmosphere storage (CA) or Modified Atmosphere Packaging (MAP) is possible in combination with low temperature.

Proper cleaning and sanitizing of building and equipment is part of good packhouse practice. Besides maintenance as prescribed by the supplier, a good cleaning and sanitizing of equipment such as the grading line is necessary prior to use. Sorting belts must be clean and have smooth surfaces. All surfaces that could lead to bruising or puncturing of fruit should be well covered for example with impact absorbing foam.