Ripening of Fruit by Ethylene Sensor.

Ripening of fruit is a problem, particularly when you want to sell that fruit. If the fruit ripens too early it will be overripe when it gets to the customer. If it is very under-ripe when it gets to the shelf the customer might not want to buy it.

It also causes a problem for transport. Ripening fruit bruises more easily and one spoiled fruit as they say can spoil the whole lot. When you are transporting a truck full of fruit this is a real problem. Fruit travel much better when they are under-ripe. Firmer, they bruise less easily. They are also less susceptible to spoiling. However fruit doesn’t taste good before it is ripe.

To sell well, fruit needs to get to customers at the perfect point between becoming ripe and being over ripe. The ability to control the ripening process is therefore very useful. It allows fruit producers and distributors to pick and transport fruit when it is under-ripe and ripen it just before putting it on the shelves.

Fruit Ripening on Demand

Throughout the lifecycle of plants ethylene (C2H4) is used as a hormone to regulate factors such as flower opening and leaf shedding. It is also used to trigger fruit ripening. This mechanism can be used to artificially ripen fruit by exposing them to controlled levels of ethylene gas.

Ethylene is created in commercial ripening rooms using catalytic generators that transform liquid ethanol into ethylene gas. Over a period of between 24 and 48 hours fruit is exposed to the gas at concentrations of between 500 and 2,000ppm.

The ethylene stimulates the fruit to begin the ripening process. By controlling the levels of exposure to the gas the fruit can be brought to the perfect level of ripeness for distribution. Depending on the distance of the distribution centre from the stores they supply the fruit can be brought to a suitable ripeness.

Controlling Gas Levels

Because the levels of ethylene need to be carefully controlled in artificial ripening centres some form of gas monitoring is required to precisely determine the levels of gas. This monitoring system can be set up to automatically control the ethylene gas production as well as ventilation systems to remove excess gas. Alarm systems can be set up to warn of gases reaching excessive or dangerous levels.

MSR Ethylene gas monitors should also be installed in areas surrounding the ripening facility to ensure containment and worker safety. Ethylene like many hydrocarbons is combustible, creating a serious hazard. It can also asphyxiate at high enough concentrations and can operate as an anaesthetic making it particularly dangerous to humans.

Monitoring gas levels in adjoining rooms will ensure workers are alerted to any leaks or hazardous levels of gas.