I'm a fruit inspector in South America. This week I inspected a load of kiwifruit from another South American country and noted small dimples on much of the fruit. What might have caused this? (H.)
I have observed kiwifruit skin pitting related to different kiwifruit handling procedures:
- Foliar calcium formulation applied during fruit growing.
- Skin freezing damage during precooling using low temperature during forced air on low maturity fruit.
- Skin dehydration during precooling on fruit cooled for long period of time and/or using high air speed in relation to fruit weight. Usually, this happens when forced air tunnels are being used below their full capacity.
- After brushing on fruit immediately cooled down to near 34-36o F, packed and brushed. Kiwifruit is less prone to skin pitting damage as a consequence of brushing when it is packed warm or brushed after some time in cold storage. This skin pitting can become a problem when fresh harvested fruit is precooled down to low temperatures immediately before brushing and packed using modified atmosphere packaging (MAP).
- Low fruit temperature exposure for long periods during storage and/or shipment. This is specially enhanced in low maturity fruit.
Additionally, the organism Cadophora luteo-olivacea also influences skin pitting of kiwifruit (Hayward) under certain conditions.