Studies of the Physiologically-Active Volatile Organic Compounds Produced by Fruits : II. The Rate of Production of Carbon Dioxide and of Volatile Organic Compounds by King Edward VII Apples in Gas Storage, and the Effect of Removal of the Volatiles From the Atmosphere of the Store on the Incidence of Superficial Scald

Abstract

The present method of controlling superficial scald of apples in gas storage by wrapping them in paper containing oil is usually very effective but is costly. This is mainly because it requires so much labour. It also takes time and delays the closing of the store. Can simpler, equally effective methods be found ? It was expected that removal of part of the volatile vapours given off by the apples, by circulating the storage atmosphere through a gas-mask type of filter, would reduce scald. This expectation was based on the theory that scald is caused by the accumulation of one or more of these volatiles in the storage atmosphere. Suitable filters were developed and experiments in which the storage atmosphere was analysed showed that these filters did remove a very large part of the apple volatiles. Nevertheless, it was found that the amount of scald occurring on unwrapped King Edward VII apples in gas storage was almost the same in a store with filters as in one without. The well-known effect of gas storage in lowering the rate at which apples lose CO₂ is shown in the present paper by means of diagrams. It is this condition which is responsible for the extension of storage life of apples in gas mixtures.