Onion Cold Storage: Design Guidelines for Vegetable Cold Storage Room

Introduction: Why Onion Cold Storage Requires Specialized Design

Onions are a semi-perishable agricultural product with unique storage challenges. Improper temperature, poor ventilation, or excess humidity can lead to sprouting, mold growth, rot, and significant weight loss.

A professional onion cold storage system is designed not only to extend shelf life, but also to stabilize product quality across long storage cycles. In commercial operations, onions are typically stored in a vegetable cold storage room engineered for airflow control, moisture management, and long-term reliability.

How Onion Cold Storage Systems Work

Storage Logic for Bulb Crops

Unlike leafy vegetables, onions require a dry, well-ventilated cold environment. The cold storage system works by:

1. Removing field heat after harvest

2. Maintaining stable low temperatures

3. Controlling humidity to prevent rot

4. Continuously exchanging air to remove gases and moisture

The refrigeration system operates in coordination with ventilation to prevent condensation and localized hot spots.

Onion Cold Storage Temperature Explained

Recommended Storage Conditions

• Long-term storage temperature: 0–2°C

• Short-term holding: 2–5°C

• Relative humidity: 65–75%

Maintaining the correct onion cold storage temperature is critical. Excess humidity promotes fungal growth, while temperatures above 5°C accelerate sprouting.

Proper control ensures onions remain dormant and market-ready for extended periods.

Core Features of a Commercial Onion Cold Storage Room

1. Insulated Room Structure

• PU or PIR insulation panels

• Typical thickness: 100 mm

• Moisture-resistant internal surfaces

2. Refrigeration System

• Medium-temperature condensing units

• Even air distribution evaporators

• Stable temperature recovery

3. Ventilation & Airflow Control

• Forced air circulation

• Continuous moisture removal

• Prevention of gas accumulation

4. Monitoring & Control

• Digital temperature controllers

• Humidity monitoring

• Alarm system for deviation

As a professional solution provider, hengliangcooling focuses on matching refrigeration capacity with ventilation performance to meet onion-specific storage requirements.

Typical Configuration for Cold Storage for Onion

A standard cold storage for onion project typically includes:

• Modular vegetable cold storage room enclosure

• Ceiling-mounted evaporators

• Axial or centrifugal ventilation fans

• Insulated access doors

• Pallet or bulk bin storage layout

System design is based on storage volume, sack or bin packaging, turnover cycle, and local climate conditions.

Key Technical Parameters (Reference)

Main Application Scenarios

Onion Farms & Grower Cooperatives

• Post-harvest stabilization

• Seasonal storage

Vegetable Distribution Centers

• Bulk onion storage

• Regional supply buffering

Food Processing & Export Facilities

• Ingredient storage

• Export-oriented cold chain logistics

hengliangcooling has delivered onion cold storage and vegetable cold storage room projects across these scenarios, adapting designs to product variety, storage duration, and operational scale.FAQ: Onion Cold Storage

What is the ideal onion cold storage temperature?

Onions are best stored at 0–2°C with controlled humidity to prevent sprouting and decay.

Can onions be stored with other vegetables?

Only with compatible dry vegetables. High-humidity produce should be stored separately.

How long can onions be stored in cold storage?

With proper conditions, onions can be stored for 6–9 months.

Is ventilation necessary in onion cold storage?

Yes. Continuous ventilation is critical to remove moisture and maintain dormancy.

Professional Hengliang Cooling

Designing an effective onion cold storage facility requires careful balance between temperature control, ventilation, and humidity management.

hengliangcooling provides professional onion cold storage and vegetable cold storage room solutions, offering customized design, refrigeration system integration, and full project execution support.
Contact the hengliangcooling technical team to discuss your onion storage requirements and receive a tailored technical proposal and quotation.