Aim for high quality strawberries
Strawberries can be grown under many different circumstances on the field, in a tunnel greenhouse, in a glashouse or even in vertical farms. The growing conditions have an influence on the quality of the strawberries. The strawberry chain is focused on delivering a high quality product. This is not always easy as strawberries are delicate products and easily damaged. Especially for strawberries it is of utmost importance to have correct handling by supply chain actors from the moment of harvest until acceptance at the final customers. Strawberries require careful handling, an in time optimised supply chain, and low temperature during transport and distribution to extend shelf-life. The difference between very careful handling and ‘normal’ handling may show after a few days in a significantly reduced damage rate. At a longer shelf-life, this difference becomes even bigger. Careful product handling and temperature management are important throughout the entire strawberry supply chain. Think in minutes rather than in hours.
Attention points in the strawberry chain
Harvesting strawberries in the field. Photo by DedovStock/Shutterstock.com
HarvestThe postharvest chain starts with the harvest. Condition of the strawberries at harvest must be such as to enable them to withstand transportation and handling and to arrive in satisfactory condition at the place of destination. Careful picking at the right maturity is critical for the quality later in the chain. The strawberries should be reduced in temperature as soon as possible.
Shaded area in the sunny field to protect the harvested crop. Photo by WFBR
Temperature managementFor strawberries, quickly bringing down temperature is of major importance. Strawberries should enter the cold room (at the packhouse) within one hour after picking, the sooner the better. In the meantime, the fruit must be protected from direct sun. A shaded shed at the field is the first step in this, followed by transport to the packhouse while protected from direct sun. Storage in the packhouse and transport from the packhouse to final destination should also be temperature controlled.
Condensation is a risk for fungal attack. Photo by SJMPhotos/Shutterstock.com
Closed cold chainA closed cold chain, thus without any intermittent warming, is very important to prevent condensation on the strawberries. Intermittent rewarming easily causes condensation on fruits (and packages) and thereby susceptibility to fungal decay. Condensation would lead mean a high risk for fungal attack with significant losses. Still it is better to accept some condensation than to accept higher product temperatures.
Grading strawberries helps in providing a uniform product. Photo by Andrej Privizer/Shutterstock.com
PackingGenerally, it should be avoided to do more handling than strictly necessary, as this increases the risk of mechanical damage. Failure to sort and discard immature, overripe, undersized, misshapen, blemished, or otherwise damaged produce (preferably in the field) creates problem in the subsequent marketing. Grading helps the handlers to categorise the strawberries according to common parameters.
Thermal blanket as pallet cover.Photo by WFBR
TransportStrawberries have a brief storage life. Ideally, transport to the market takes place at the day of picking. The use of refrigerated trucks or other means of refrigerated (air) transport is very important, without breaking the cold chain. During transport, temperature monitoring takes place. Foil laminated thermal blankets can be used to cover a pallet with strawberries if cold chain temperature cannot be guaranteed during transit, for example at the airport.
Strawberries are susceptable to fungal infection. Photo by RussieseO/Shutterstock.com
CA and MAAn optimal temperature is the first requirement to maintain good quality strawberries. In addition, the storage life can be extended somewhat by applying Modified Atmosphere Packaging (MAP). Whole pallet covers can be used for this purpose. A high CO2 level reduces mould growth (Botrytis), but too high CO2 can cause off-flavours.
Strawberries in the supermarket. Photo by TeeraPhoto/Shutterstock.com
RetailStrawberries should look fresh, be sound and clean. Fruit condition in the shop must be sufficient to ultimately arrive at the consumer's home in satisfactory condition. As shelf-life of strawberries is short, following best practices is essential. So keep them refrigerated, remove packages with diseased fruits, and include first-in, first-out inventory management unless quality indicates otherwise. Discard overripe and diseased fruits.