STORAGE OF APPLES

Poverty Bay Herald, Volume LX, Issue 18068, 20 April 1933, Page 7

STORAGE OF APPLES

THE EFFECT OF GASSES EXTENSIVE EXPERIMENTS LONDON, March 14. During tile season 19,51-32, says the report of the Department of Scientific and Industrial Research, a large-scale experiment on the behavior of four varieties of English apples at three temperatures and m various mixtures of oxygen, nitrogen and carbon dioxide, has been brought to a successful conclusion. Three points of major .importance have emerged from tiio results. In the first place, the experiment lias demonstrated that gas-storage, as employed on a commemaLsf.alo for Brainley’s Seedling, is ;dlw--applicable to Lane’s Prince Albert. Secondly, the wide scope of the experiment has thrown much light on the casual conditions ol certain obscure types of injury which had often been observed in apples carried under refrigeration to tins country from Australia and New Zealand. Thirdly, the importance lias been emphasised of adequate control of temperature when carbon dioxide is present, even in concentrations as low as 5 per cent.

The experimental hold at the Ditton Laboratory enables experiments on the control of temperature, humidity and the composition of the atmosphere during the storage in bulk of foodstuffs which react with their environment, to be carried out on a scale yielding results of immediate practical application, and some* interesting data are already available. Measurements of the various thermal quantities involved have made it, possible to draw up a balance-sheet from which the rate of generation of beat by the fruit can be estimated; the chamber w as thus made to play the part of a calorimeter for determining a biological constant. The distribution of temperature inside the stack of fruit is being studied as a function of the system of refrigeration employed, the direction and speed of air movement and 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 attracted attention. The transfer of heat from fruit to air 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 practical result is that to transfer heat from fruit to air 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 bolds under such conditions would fail to give even ail approximately true indication of the actual temperature of the fruit.