DR. KIDD'S WORK

Evening Post, Volume CIV, Issue 70, 20 September 1927, Page 10

DR. KIDD'S WORK

The present series of studies on fruit transport problems, iv which Dr. Kidd and" other scientists are engaged, began in 1923 with the sending to Australia of a small scientific expedition whose immediate objective was an investigation of the abnormal condition in apples known as brown heart. The results of this expedition, which have been published in part, were decisive as regards this immediate problem. At the same time they served to reveal many other matters of practice -in 1 which the aid of the scientist was needod, but in which the knowledge- available was inadequate for a solution of tho difficulties. Two problems in particular appeared to be both fundamentally important and ripe for systematic attack —the question of temperature control in the ship's refrigerated holds, and that of the development of bitter pit in the cargo during transportation. These were tho matters to which attention was mainly directed in the second expedition to Australia.

The disease of brown heart was definitely shown by the laboratory experiments of Dr.' r. Kidd and Dr. C. West, and by tho results of the expedition of 1923, to be tho result of inadequate ventilation of the fruit during storage. Ventilation is necessary because apples generate carbon dioxide, and use up oxygen from the air, in the same way that a human being does in breathing. Only a relatively small amount of ventilation is, however, essential, since apples will tolerate moderate amounts of carbon dioxide and moderate deficiencies of oxygen, and indeed will keep longer in such atmospheres than in ordinary air.

In holds where the air is circulated more or less continuously by means of fans, more than sufficient ventilation is usually socured accidentally, by leakages in the air circuit. On tho other hand, in holds not employing air circulation, that is, roughly speaking, in holds with the grid system of refrigeration, the accidental leakage is not always sufficient to afford the required ventilation. It is necessary, therefore, to provide these vessels with special moans of ventilating tho holds, and with instruments to show when ventilation becomes necessary.

' With the recognition of these facts and the general adoption of these recommendations by tho trade, it may be anticipated with the greatest confidence (state the scientists) that-the disease of brown heart will cease to be of commercial importance. The ships engaged in the fruit trade now possess means of ventilating their holds.

The implications of the ventilation problem are wider, however, than the avoidance of brown heart. Holds of the grid system, when not indiscriminately ventilated, are sufficiently gastight to offer possibilities for fruit preservation under gas-storage conditions. These possibilities have yet to be fully explored.