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The overarching principles, however, remain consistent: the rapid removal of field heat immediately after harvest; as well as maintaining the moisture content – with the intent that the consumer enjoys the fruit quality as when it was hand-picked.

The stage of maturity at harvesting differs across the broad spectrum of

Pre-harvest in the winelands.

fruits. Freshly harvested table grapes or golden delicious apples are crunchy to eat whereas those harvested when green, bananas or avocados, cannot be eaten until allowed to ripen. Certain fruits are allowed to ripen on the plant whereas others ripen after harvesting.

Post-harvest is not just about removing field heat but also the de-greening of citrus or sterilisation for the control of pests which is a requirement for various markets into which the fruit is being exported. Once harvested, fruits are typically transported to an on-farm facility for initial cooling. While some operations utilise rapid cooling tunnels for swift temperature reduction, the

specific equipment and methods employed vary significantly depending on the fruit. Some fruits undergo an initial heat removal before being placed in a holding area for further processing and cooling. It ' s at this stage, prior to final packaging in boxes, cartons, trays or punnets, that the fruit ' s core temperature begins its descent towards optimal storage conditions or for the start of a long logistics chain.

Ackermann notes that complexity arises in that the post-harvest process aims to bring the fruit to the required temperature before it enters the supply chain, but also taking into account its final destination.“ Simultaneously, maintaining the correct moisture content is crucial to prevent dehydration and ensure a prolonged storage life, ultimately delivering quality produce to consumers, even those in distant markets.”

A fascinating aspect of post-harvest handling is the different controlled ripening of particular fruits, such as bananas. Unlike many other fruits transported at their peak ripeness under controlled temperature, bananas are typically harvested and shipped green to prevent spoilage during transit. The ripening process, occurring in specialised facilities near the point of sale, is a distinct yet integral part of ensuring consumer satisfaction.

For some fruits, it’ s a fine line between the post-harvest and ripening processes, whereafter the consumer can eat it. " The ripening process of bananas is a different

John Ackermann, founding chairman of SARDA.

process," Ackermann clarifies. " Bananas are generally transported green to the ripening room- you ' ve got to trigger off the ripening process by using ethylene." This involves placing the green bananas in a controlled, near-airtight ripening room with ventilation, and introducing a specific percentage of ethylene gas. This natural plant hormone initiates the ripening process, allowing the bananas to reach optimal ripeness for retail within a predictable timeframe, typically a few days. Notably, ripe bananas are not stored under refrigeration in supermarkets; they are displayed at room temperature.

The equipment and infrastructure required for effective post-harvest handling are directly dictated by the specific needs of each fruit. For instance, apples and pears destined for long-term storage often

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