ISO 3959:1977

Overview

ISO 3959:1977 - "Green bananas - Ripening conditions" defines recommended postharvest ripening protocols for green bananas intended for international trade. The standard describes pre-ripening factors, placing and loading in the ripening room, heating procedures, ripening phases, the action and safe use of ethylene, post-ripening storage temperatures, target degrees of ripeness at supply, and common causes of defective ripening. It was developed by ISO/TC 34 (Agricultural food products) and complements storage and transport guidance.

Key topics and technical requirements

• Pre-ripening assessment: degree of development at harvest is judged by fruit fullness on the bunch; external and physiological conditions during handling and transport strongly influence ripening performance.
• Placing and loading: hands/parts of hands are usually sent in corrugated fibreboard cases; recommended loading density in the ripening room is 150–200 kg/m³; maintain airflow corridors between pallet rows.
• Heating stages:
  • Preliminary heating: natural warming if external temperature >12 °C; artificial heating if below 12 °C to prevent cold injury.
  • Supplementary heating: raise flesh temperature progressively to the target ripening temperature (typically 16–18 °C) in a humid, closed-circuit atmosphere.
• Ripening phases: two physiological phases - an initial climacteric heat and respiration rise, then a decline accompanied by starch hydrolysis and skin colour change. Maintain relative humidity ≈95% during ripening and keep air circulation to homogenize temperature.
• Ethylene use: ethylene accelerates and standardizes ripening of otherwise unripe fruit. Typical treatment uses ~1 000 ppm (1 part per 1 000) ethylene or controlled nitrogen/ethylene mixtures supplied from cylinders placed outside the room; room should remain closed for 24 hours after introduction. Note: national regulations on ethylene use apply.
• Ripening schedules: example regimes in the standard include rapid (≈4 days), normal (5–6 days) and slow (≈8 days) ripening with day-by-day temperature and humidity guidance.
• Post-ripening storage & supply: target flesh temperature after ripening is about 13.5–14 °C for summer supply (turning yellow); in cold weather supply, fruit may be firmer/yellower with flesh temperature around 16 °C.
• Causes of defective ripening: cold injury, dehydration, low RH, injuries, uneven development, fungal infections.

Applications and who uses it

ISO 3959 is practical for:

• Banana ripeners and packing houses setting up ripening-room protocols
• Importers, wholesalers and retailers managing delivery ripeness
• Cold-chain and logistics managers coordinating transport and pre-ripening handling
• Quality assurance and postharvest researchers developing SOPs for banana ripening
• Regulators and auditors assessing commercial ripening practices

Keywords: ISO 3959, green bananas, ripening conditions, ethylene treatment, ripening room, banana ripening, storage temperature, postharvest handling, ripening protocols.

Related standards

• ISO/R 931 - Green bananas - Guide to storage and transport (referenced by ISO 3959)