Apparatus for the Measurement of Gaseous Conditions inside an Apple Fruit

1. Two forms of apparatus are described, one for the routine analysisof the internal atmosphere of an apple fruit and another forthe measurement of (i) carbon dioxide output, (ii) internalgas concentrations, (iii) atmospheric pressure within the fruit,(iv) permeability of the fruit to gases.
2. The use of thesetwo apparatuses to follow changes within thefruit as a resultof the application of a skin-coating is describedand the resultsobtained are discussed.
3. It is shown that the fall in pressurewhich occurs as a resultof the cooling of the fruit due toevaporation of the appliedcoating can only form a small fractionof the total fall inpressure observed as a result of the applicationof the coating.
4. It is shown that coating the fruit with anoil-water emulsioncauses a deficit in the combined concentrationof CO₂ and O₂within the fruit below the 21 per cent, observedin similaruncoated fruit.
5. An explanation of this phenomenonis advanced, and it is suggestedthat the modification of theinternal atmosphere brought aboutby the skin-coating, if itcan be suitably controlled, willprove valuable in increasingthe cold-storage life of apples.

The work described in this paper was carried out as part ofthe programme of the Food Investigation Organization of theDepartment of Scientific and Industrial Research.