Overview
ISO 1134:1993 - Pears - Cold storage provides practical, international guidance for the successful cold storage of common pear varieties (Pyrus communis) from harvest to fresh-market use. The standard covers harvesting criteria, optimum storage conditions (temperature, humidity, air circulation), controlled‑atmosphere (CA) storage, and storage in plastic packages, and includes informative Annexes A (example CA regimes) and B (grower role and common storage disorders).
Key topics and technical requirements
- Harvesting criteria: Maturity assessment by skin ground colour, flesh firmness (spring penetrometer), soluble solids (≥10% by refractometer), ease of separation and starch test (iodine/KI). Optimum harvest timing may vary by variety and region.
- Pre‑storage handling: Rapid removal of field heat and precooling; careful handling and sorting to put only sound, clean fruit into store.
- Storage temperature: Generally as low as possible without freezing; typical preferred range is about −1 °C to +0.5 °C. Temperature differences of 1 °C greatly affect storage duration.
- Relative humidity: Recommended 90–95% RH to limit shrivelling and mass loss.
- Air circulation and storage density: Typical storage density ~250 kg/m³ usable space; ventilation around 80–100 m³/h per tonne or an air circulation ratio of 20–30.
- Controlled‑atmosphere (CA) storage: Suggested CO2 and O2 guides (e.g., CO2 1–3%, O2 ~2–5%) depend on cultivar and local practice. Avoid CO2 >5% for varieties susceptible to “brown heart”; liners should be perforated and CO2 within liners kept ≤3% to prevent core browning.
- Ripening after storage: Recommended ripening temperatures 15–18 °C; ethylene treatment (commonly 1–2% at ~18 °C and ~90% RH) may accelerate uniform ripening.
- Plastic packaging: Suitable food-contact films with perforation can reduce mass loss and extend storage life by 4–8 weeks for some cultivars.
Applications and users
ISO 1134:1993 is useful for:
- Fruit growers and orchard managers setting harvest criteria and pre‑storage practices
- Cold‑store operators and packhouses optimizing storage regimes, ventilation and CA systems
- Cold‑chain logistics managers and exporters ensuring fruit quality during distribution
- Post‑harvest researchers and extension specialists addressing physiological disorders (scald, brown heart, internal browning) and storage loss reduction
- Food safety and quality managers aligning handling and storage to international good practice
Related standards
- ISO 2169:1981 - Fruits and vegetables: physical conditions in cold stores (definitions and measurement)
- AGRI/WP.1/EUR.STAN.1 - Revised European guidance for apples and pears (referenced in ISO 1134)
ISO 1134:1993 gives general, variety‑specific guidance and should be adapted by specialists to local climates and cultivar behavior for best results in pear cold storage.