Research for fruit industry

Press, Volume CXII, Issue 32848, 23 February 1972, Page 16

Research for fruit industry

More than $11,500 worth of new equipment installed this week at the University of Canterbury’s department of botany might have an important bearing on the New Zealand fruit industry.

The equipment, a centrifugal freeze dryer and a specrometer will be used by a senior lecturer in the department, Dr J. R. L. Walker, to isolate the compound which inhibits an apple’s defence mechanism when it is attacked by blue mould. In a typical firm rot such as that caused by infection (brown rot, or bitter rot) the rotted tissue is usually darkbrown in colour and the apple’s flesh remains relatively firm. By contrast the soft rot (blue mould) is light coloured, whilst the apple flesh is almost liquid in consistency, and the rot spreads rapidly.

membered that the size of an article, and the nature of it, vegetable or mineral, make great differences to freezedry times.”

Whereas a leg of lamb might take up to three weeks to freeze-dry, the same process could be achieved in three days if it were cut into thin slices.

Apart from the i-esearch which Dr Walker will conduct on apple diseases, he will also use the new equipment for research into the metabolism of micro-organisms that break down the organic materials in the soil.

Another study will concern diseases which attack a plant when it is placed with the same type of plant but in a new setting.

Until now it had been almost impossible, Dr Walker said, to isolate enough of the compounds that stopped the apple protecting itself against blue mould.

Known as specific replant disease, this also is cf great concern to New Zealand fruit producers when it comes to renewing trees in an orchard, Dr Walker said.

“With the freeze dryer I will now be able to take a large quantity of liquid containing perhaps a microscopic amount of the compound and preserve it for study,” he said.

As the compound was sensitive to heat only the freezedry method could be used to collect it, he said.

Dr Walker said it was hoped that the freeze dryer could also be used to preserve small animals and insects for the biology department.

A number of local food processing companies had also expressed an interest in having the botany department conduct research into pilot food schemes.

“You can freeze-dry almost anything,” Dr Walker said. “The problem is packaging for later use; and it must be re-