Kidd and West stored apples by changing the air, not the temperature, to add a season.

English apples, unlike imported ones, spoiled quickly once taken out of cold storage, so growers were losing a crop that should have lasted the winter.

Franklin Kidd and Cyril West at Cambridge found that if oxygen is reduced from about 20% to near 10% and carbon dioxide is raised, an apple keeps breathing but far more slowly, prolonging its life by months even at low temperature.

In 1929 grower S. W. Mount built the first commercial gas store near Canterbury, based on their research, holding 30 tons of Bramley's Seedling; by 1935 there were 40 such stores with 400,000 bushels of capacity.

The technique, renamed controlled atmosphere in the 1940s, spread worldwide: a way to hold the autumn crop past the winter and sell fruit out of season at stable prices.

Slow the fruit's own breathing and it waits for the market

A fruit keeps respiring after picking; the atmosphere controls how fast

Lower O2 and higher CO2 buy months, not just weeks

One store's atmosphere is cheaper than a fleet of cold trucks

When you cannot stop decay, slow the cause of it: manipulating the atmosphere can stretch a perishable from weeks to months, smoothing prices without adding cold trucks or warehouses.

By the 1940s the method was rebranded controlled atmosphere and adopted around the world; in some countries over half the apple and pear crop is still held in CA rooms, extending shelf life and letting growers sell into the off-season.