The fruit you eat may not be so sweet

As supply does not meet the demand, traders artificially ripen mangoes

Come summer and the sales of fruits, especially mangoes, increases exponentially. People see it as the safest and the tasty way to beat the intense heat of the season, and the dehydration that accompanies it.

A large district such as Coimbatore consumes, according to a conservative estimate, over 15 tons of mangoes every single day during peak summer.

However, the supply does not always meet this huge quantum of demand for a multitude of reasons and unscrupulous traders, intent on making a quick buck, resort to illegal measures to artificially ripen not only mangoes, but a whole gamut of fruits that sell well now.

More than 3.5 tons of artificially-ripened chikoo (‘sapota’) were seized from just two shops last year, indicating the scale of the problem, says R. Kathiravan, Designated Officer, Tamil Nadu Food Safety and Drug Administration Department (Food Safety Wing).

Explaining the process behind artificial ripening, he says ethylene gas initiates the ripening process in a fruit. Normally, several other processes follow this step, including the conversion of starch to sugar, the crucial step which makes mangoes so mouth-wateringly tasty.

However, in an artificially ripened fruit, only the chlorophyll (green pigment) changes color and none of the other natural processes take place. This results in a seemingly ripe fruit tasting very sour.

The process

Among the most common method for artificial ripening, he says, is the use of calcium carbide - primarily due to its easy availability and cheap cost - which emits acetylene gas when mixed with water. Calcium carbide is predominantly used in arc welding.

Just one kilogram of this substance, brought for as little as 30 bucks can ripen around 10 tons of fruits. For example, he says raw fruits of the much-sought after Imam Pasand mango can be procured for half its market price, ripened using a kilogram of carbide and sold for the market price, resulting in a 100 per cent profit.

The calcium crystals, Dr. Kathiravan says, are kept among the stones for 12 hours, mostly during the nights making it difficult to catch the errant traders.

Other less-common methods include the use of Ethiphon, a pesticide in liquid form which is diluted and sprayed on the fruits, and Oxytocin, a hormone injected into the fruits.

Health hazard

The major health hazard is the acetylene gas emitted by calcium carbide. This targets the neurological system and reduces the oxygen supply to the brain.

While short-term effects include sleeping disorders and headaches, he says the long term effects are memory loss, seizures, mouth ulcers, skin rashes, renal problems and possibly, even cancer.