🌷 Ripening Chemicals

Chemical regulation of ripening is used in post-harvest systems to either hasten market readiness or delay senescence for longer storage and transport.

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Chemicals for Hastening Ripening

Growth regulator treatments such as 2,4-D, 2,4,5-T, and related compounds have been reported to influence ripening behavior in certain crops.

Ethephon promotes degreening and faster ripening in crops such as grape, tomato, coffee, pear, plum, peach, and citrus.

Traditional smoking has been used commercially for banana and mango ripening.

Calcium carbide releases acetylene and can hasten ripening, but unsafe carbide use is not recommended in food systems.

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Chemicals for Delaying Ripening

Compounds such as kinetin, gibberellins, auxins, MH, Alar, CCC, CIPC, and other metabolic modulators have been described for delaying ripening under specific conditions.

Ethylene absorbents (for example KMnO4-impregnated materials) can reduce ethylene concentration in storage spaces and improve shelf life.

Low oxygen storage (around 2-3%) can also delay ripening in crops such as banana and apple.

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Practical Considerations

The treatment response depends on crop, maturity stage, dose, and timing. Pre-harvest sprays and post-harvest dips should only be used under recommended protocols.

Poorly controlled chemical use can harm quality, safety, and shelf life.

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Summary Cheat Sheet

Objective	Common approaches	Notes
Hasten ripening	Ethephon, ethylene exposure, smoking	Useful for synchronized marketing
Delay ripening	GA, MH, CCC, ethylene absorbents	Extends storage/transport window
Reduce ethylene effect	KMnO4 absorbents, low O2 storage	Slows climacteric progression
Improve outcomes	Correct dose and stage	Avoid non-standard or unsafe use

References

2 sources • [1] [2]

[1]

UC Davis Postharvest Technology Center

Reference

[2]

FAO - Food and Agriculture Organization

Reference