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Hokitika Guardian, 26 April 1933, Page 4

A large scale expon m<-it cri the behaviour of f ur varieties of English

apples, states the report of the Department of Scientific and Industrial Research, at three temperatures, and in various mixtures of oxygen, nitrogen and carbon dioxide, lias been brought to a .successful conch;,: ion. Three points of major importance have enieiged from the lesultv. In the

first place, the experiment has demonstrated that gas-storage, as employed on a commercial scale , for Biviro ley’s Seedling, is also applicable to lame's Prince Albert. Secondly, the wide scope of tbs experiment has thrown much light on the casual conditions of certain obscure types of injury which had often been observed in apples carried under refrigeration to this country from Austn lia and New Zealand. Thirdly, the importance has been emphasised of adequate control of temperature when carnou dioxide is present, even in concentrations as low as 5 per cent. The experimental hold at D-itton Laboratory enables experiments on the control cf temperature, humidity and the composition of the atmesoliere during the storage in hulk of foodstuffs which react with their en-

vironment, to be carried out cm a scale yielding remits of immediate practical application, and some interesting data are already available. Measurements of the various thermal quantities involved have made it pocigible to draw up a balance-sheet from which the rate of .generation of heat by the fruit cun be estimated; the chamber was thus made t-o play the part of a calorimeter for determining a biological constant. The distribution of temperature inside the stack of fruit k being studied as a function of the system of refrigerating - employed, the direction and speed bf airmovement end the method of stowing the cases. The system of a few wide vertical channels employed in preference to the more customary method of stowage with small horizontal laths has already ntracted attention. The transfer of heat from fruit to dr is an integral part of the refrigerating process which so far has received scant attention; it is being studied in the experimental hold. An important liractical result is that to transfer heat from fruit to Mr at a rate equal to that of its production by the fruit may require a fall in temperature so considerable that measurements of temperature in the air of ship’s holds under such conditions would fail to -rive even an approximated true indication of the actual temperature of the fruit.