The key difference between a controlled atmosphere storage and a regular cold storage is that the freshness logic is completely different: a regular cold storage just slows down spoilage with low temperatures, while a controlled atmosphere storage precisely adjusts the gas composition inside on top of the low temperature, suppressing the respiration of fruits and vegetables from the root and extending their freshness several times.
Differences in Core Fresh-Keeping Principles Ordinary Cold Storage: Only slows down microbial activity and enzymatic reactions through a low-temperature environment of 0-10℃, which is ‘passively delaying spoilage’ and cannot fundamentally inhibit the respiratory metabolism of fruits and vegetables. Controlled Atmosphere Storage: Uses a triple preservation barrier of 'low temperature, low oxygen, high carbon dioxide,' controlling oxygen concentration at 2%-5% and carbon dioxide concentration at 3%-8%, putting fruits and vegetables into a near-dormant state and delaying metabolism from the root.
Differences in Freshness Effect and Duration
Ordinary Cold Storage: The usual freshness period for common fruits and vegetables is only 1-4 weeks, with long-lasting varieties like apples lasting up to about 6 months. After being taken out, their shelf life is short and they easily soften and spoil quickly.
Controlled Atmosphere Storage: The freshness period is 0.5-1 times longer than ordinary cold storage. Apples can be stored for up to 11 months, and their shelf life after being taken out is 4-5 times that of ordinary cold storage. It maximises the retention of firmness, colour and nutrition of fruits and vegetables, with natural loss rates controllable at 3%-5%.
Difference in equipment and construction costs Ordinary cold storage: only requires basic refrigeration compressors, air coolers, and other equipment, with low airtightness requirements. The usual cost is about 600-1000 CNY/㎡, with low initial investment. Controlled atmosphere storage: additionally requires nitrogen generators, carbon dioxide removal machines, ethylene removal machines, and intelligent gas monitoring systems. The storage must be strictly airtight (pressure drop time ≥20 minutes under 300Pa), costing about 1-1.5 times that of ordinary cold storage, with an initial investment 30%-50% higher.
Usage methods and differences in suitable scenarios Normal cold storage: Supports opening and closing anytime for loading and unloading goods, suitable for items like meat, frozen foods, and short-turnover fruits and vegetables that are not sensitive to gas environments, fitting for fresh food supermarkets and small restaurants. Controlled atmosphere storage: Must load and unload in full batches, frequent opening and closing of the door can disrupt the gas balance, specially suited for long-term storage of high-value fruits like apples, pears, kiwis, and grapes, helping farmers achieve off-peak sales and off-season price premiums, making it the preferred solution for large-scale fruit and vegetable bases in Shaoxing,Zhejiang,China.
