Where oranges are originally green

Oranges are green, not orange

Thoughts, biodegraded

In the meantime I don't buy oranges anymore in November because disappointment is inevitable. The fruits do not keep what their bright color promises. They are dry and straw-like, taste sweet but have no aroma. This is no coincidence, because the peak of the citrus season is around Christmas, when the main harvest in the Mediterranean countries is brought in. And how juicy and tasty the fruit really is has little to do with the color of the skin. So it is not surprising that the name of the fruit has nothing to do with the color of its skin.

Oranges are not orange.

Oranges do not owe their name to the color of their skin, it is exactly the opposite. The name comes from the South Asian homeland of the fruit, which is also suggested by its other name “orange” for “Chinese apple”. The word "orange" goes back to a root word "naran [g / j] a", which means something like "fragrance". It is not the degree of ripeness but the nighttime temperatures and the availability of nitrogen and water that determine the color. Only in countries with distinct seasons and cool nights do the fruits develop the ripening color that is typical for us. This is the case in the European Mediterranean area and so the fruit could possibly only pass on its name to the color yellow-red in our country. In any case, oranges stay green all year round in their tropical home countries.

The following photo shows fully ripe dark green oranges from a Thai market. I don't think our uniformly orange oranges taste better. The opposite may be the case, because the oranges and clementines from the Mediterranean area only naturally turn orange from around January.

For years, the EU has classified oranges according to their color, not according to taste or juiciness. As a result, the dubious practice of de-greening has spread, giving the often blotchy and slightly differently colored individual fruits a uniform color. If greenish fruits are harvested in the preseason, you can help.

To do this, the fruits are fumigated with the plant hormone ethylene for an exact period of time at a meticulously set temperature and humidity. This allows you to set the hue and evenness very precisely, but it also irreversibly accelerates the aging process of the fruit. It can lead to the formation of off-flavors, the acids in the fruit are broken down, it becomes more susceptible to cold damage and fungal attack. It is precisely because of the latter that they are bathed in wax mixed with pesticides, which then sticks to the fingers when peeled and thus gets into the body when consumed. Because the calyx is more easily detached from the fruit when gassing, it can be treated beforehand with the pesticide 2,4-D. These are all avoidable pesticide applications that are not intended to improve the quality of the fruit, but only to alleviate the side effects of a dubious color correction.

Almost more curious than the direct de-greening of the fruit is how you treat the trees. In summer part of the bark is removed from the orange trees, or a wire loop is pulled around the trunk. This "ringing" and "gagging" is supposed to hinder the flow of sap and move the tree to an emergency ripening of its fruits.

The expensive and perishable straw fruits at the beginning of the season are simply not ready yet. Citrus fruits have to be harvested when they are ready to eat; unlike bananas, for example, they are not capable of post-ripening. Treatment with ethylene can only do harm.

via Dr. Ulrike Bickelmann and Udo Pollmer

Martin Ballaschk holds a PhD in biology, but is interested in many other natural sciences. The blog serves as a digestive organ for his thoughts. Professionally he works as a science communicator, here purely privately.

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