Fruit Ripening (Ethylene Gas)

Fruit ripening is a biological process in which ethylene gas is generated by the fruits which in turn also acts in causing further acceleration of the ripening process.

Thus one can start and trigger the process of ripening of fruits by introducing ethylene in some form.

It is also known that the ripening can be started by introducing acetylene; acetylene is generated by keeping small quantities of calcium carbide particles or dust. This carbide while coming into contact with moist atmospheric air causes generation of acetylene which in turn warms up the atmosphere as well as known to trigger the ripening in fruits.

It is suspected that the ripening process is accelerated since acetylene imitates ethylene. Since the amount of carbide needed to ripen the immature fruit is more it makes the fruit become more tasteless and toxic. Also commercially available carbide is known to contain trace amount of arsenic and phosphorous in carbide that can make the healthy fruits poisonous.

It is also known that the fruit ripening using calcium carbide is banned by Govt. of India.

Ethylene also can be generated from ethanol and other ethylene derivatives. However ethanol is a restricted items as this can be used as and imbibed as an alcohol and thus possession of ethanol can lead to avoidable inquiries and harassment by many govt. and police authorities.

Use of ethylene in pure form in small and safe quantities or as safe mixtures of ethylene and nitrogen are the recommended and best methods for ripening of fruits.

Tripti Gases Pvt.Ltd India Private Limited recommends use of its products

• A Gas mixture Ethylene 5 % and Nitrogen 95 % in compressed gas cylinders
• Perfect Fruit” supplied in 400 to 450 ml cans

The quantity supplied in sealed cans is safe as long as the seals are not broken. The quantity in each can is adequate to ripen approx. 3 to 4 tonnes of bananas when mixed with air in a sealed chamber

Why Ethylene?

Ethylene is an agent in the fruit ripening process. Most of the fruits elute ethylene gas as they ripen and other is sensitive to it. The process of ripening is triggered and accelerated, if the atmosphere surrounding the raw fruit is injected with trace of ethylene gas. The process of fruit ripening with external ethylene injection does not affect the flavor and taste of the fruit.

The concentration of ethylene that is required to be maintained in the atmosphere during the soaking period is decided by the size of the room/chamber and the type of fruit. One canister shall result in a concentration of approx. 100 ppm of ethylene in a room/chamber of size 3M*4M*3M, with a volume of 36cubic meter (36000litrs).

How to use: Store the fruit in plastic crates/tray in a gas tight room or a chamber to avoid physical damage to the fruits. Reduce the room temperature to prescribe temperature for the fruit. (15 to 18 Deg. C for bananas). Break the seal of the canister valves and press the canister valve to release the gas into the room/chamber. Empty the canister completely. Care should be taken that the operator is not exposed to gas eluting from the canister. The room should be gas tight and shall have adequate air circulation facility to ensure that the concentration within the room is distrusted and uniform. After the prescribe time (for banana 24 hours). Open the doors of the room for 20minutes. Six hours for the next 24 hours to ventilate the room and remove CO2 from the room. Remove the fruit crates for strong and transport to next stage.

Fruits are ripened with ethylene exposure at certain prescribed Temperature and Relative Humidity level of 90-95%. Following is broad guide for fruit ripening condition.