Post Harvest Management of Horticultural Crops

Artificial ripening

Artificial ripening of fruits

In the past, acetylene gas was used as a replacement to naturally released ethylene to enhance the ripening of fruits. Though the acetylene triggers ripening process in fruits, it is an inflammable gas involving risk of fire hazards. Calcium carbide is used as a source of acetylene gas which when comes in contact with water vapour present in the atmosphere releases acetylene gas. However, calcium carbide contains chemical impurities such as arsenic hydride and phosphorus hydride that are highly carcinogenic compounds. Improper use of calcium carbide can therefore cause chemical contamination of fresh produce. Further fruits ripened with calcium carbide though develop attractive surface colour, are inferior in taste, flavour and spoil faster. Government of India has banned the use of calcium carbide for ripening of fruits under PFA Act 8-44 AA, 1954.



Ethylene is recommended in place of acetylene for enhancing the ripening fruits. 2-chloroethane phosphonic acid (available with trade names of Ethrel or ethaphon) is a commercially available plant growth regulator that can be used is a source of ethylene. This ethylene is similar to that naturally released by fruits during ripening process.

Advantage of controlled ripening

• Improved uniformity of ripening among fruits
• Minimizes the development of rots
• Product reaches consumers at the right stage of maturity


Majority of world banana is ripened under controlled condition. It can also be carried out on tomatoes, melons, avocados, mangoes and other fruits.

Ethylene is known as ripening gas, which is a low molecular weight hydrocarbon.

Non climacteric fruits will not respond to artificial ripening with little or no desirable changes in the composition after harvest and are not harvested until they fit are for consumption.

Optimum ripening condition for fruits

Temperature	18-250C (<18delay ripening, > 25 microbes )
RH	85-90%
Ethylene conc.	10-100 ppm
Duration	12 -72 hr
Air circulation	sufficient to maintain the air temperature
Ventilation	sufficient to prevent accumulation of CO2


The Process of ripening