Fruit ripening: importance of artificial fruit ripening in commercial agriculture and safe use of the technology for consumer health

Fruit ripening is the final phase of fruit development, which results in various physicochemical, nutritional and organoleptic changes of fruits including changes in taste, texture, appearance and aroma. Ethylene (C2H4), which is a gaseous plant hormone, plays a key regulatory role in fruit ripening. Ethylene is described as an autocatalytic agent as the exposure of fruits to small quantity of ethylene could induce the production of its own ethylene in larger quantities. Various changes in the matrix of the fruit tissues such as breakdown of chlorophyll, conversion of starch into sugars, large organic compounds to small organic compounds, and pectin to less soluble forms take place triggered by such ethylene produced within the fruit. However, due to the soft nature, the naturally-ripened fruits may be subjected to mechanical damages during transportation leading to loss of consumer attraction. Therefore, mature fruits are ripened artificially before sale to meet the increasing demand and to ensure their cosmetic appearance. Many fruit wholesalers make fruits ripen using artificial ripening agents’ such as calcium carbide, ethylene, ethephon and smoke. Most of the chemicals used as ripening agents accelerate fruit ripening, change the nutritional quality of fruits and are harmful for human health. Therefore, it is important to build an awareness among fruit producers, traders and consumers on the correct selection and use of fruit ripening methods. This review discusses the research-based knowledge shared across the world on fruit ripening, major physicochemical changes in the fruits during the ripening process, commercial ripening agents, and how such different ripening agents affect the fruit quality and consumer health.