Fruit and ripeness

I watch him for a long time from where I stand in the green section. He seems to be nice enough, beaming with service-mindedness as he goes on replacing the entire shelf of bananas with new ones, putting the old ones in a worn out carton box. I can’t figure out why the clerk is doing this, the only difference being that the new bananas are a bit greener than the replaced ones. But maybe my confusion comes from the absence of caffeine this morning. I can’t help it. I need to ask him.

‘Excuse me, is there anything wrong with those bananas?’

‘No’ he answers with an apologetic expression. ‘It’s just that they don’t sell when they’re ripe’.

There are several tips for preserving fruit and vegetables. One of them is to keep them cooled, since all chemical processes are slowed in lower temperatures, including ripening. Another is to handle them with care during all transportation.

Climacteric fruit

Climacteric fruit have a changing ripening process, during which the fruit soften, change color and change taste. Bananas, pears, apples and tomatoes are examples of climacteric fruit. 

A key quality to the ripening of climacteric fruit is that it is rich in ethylene, a growing hormone that accelerates the ripening process and aging in the fruit itself and in others lying close by. A tomato may accelerate the ripening of avocados if you put them next to each other at room temperature, among other things.

But while climacteric fruit is usually rich in ethylene, it is also more sensitive to it. That is why we need to keep this type of fruit in cold places, to slow down the ethylene production and keep the fruit fresh for longer. But some greens will not keep well in the fridge. A good guide line is that tropical sorts, such as banana, avocado and mango need to be kept in a warmer climate, in other words room temperature. If these are put in the fridge, they will lose some of their best qualities. 

Non climacteric fruit however (such as pineapple and grapes) are not so sensitive to ethylene and therefor keep longer generally.

So, in other words. 

• Most fruit is best kept in the refrigerator.
• Some tropical fruit, though, is not. For example bananas should be kept at room temperature.
• Climacteric fruit that isn’t tropical should be kept chilled as long as possible. It should also be kept separated from other fruit if you don’t want it to ripen quicker. Keep this in mind when you fill your fruit basket! 

In the end, though, I’d like to emphasize the best way to know if a fruit is good to eat or not:

Peel it and have a look inside. Most bananas don’t need to be thrown into the bad carton box.

Sara Dahlgren