FOR THE ARMY

Waihi Daily Telegraph, Volume XXXII, Issue 8872, 12 February 1943, Page 3

FOR THE ARMY

FOOD DEHYDRATION VEGETABLE SUPPLIES SUCCESSFUL STAGE REACHED The Hon. D. G. Sullivan. Minister in charge of the Department of Scientific and Industrial Research. recently reviewed the research and developmental work in vegetal.de dehydration which has been initiated in Mew Zealand by his department, nnd now been successfully brought to the stage of full-scale commercial production for the Armed Forces. Flesh vegetables contain from Si) to !>."> per cent of water, and the aim of dehydration is to remove almost; the whole of that water (dried vegetables contain from 2 to -1 per cent of water) without impaling in any way the dietetic value of the food and without affecting to any appreciable extent the appearance and natural flavour of the vegetables when they are ultimately reconstituted in water and cooked for use. Saving Of Weight The main advantages of dehydration lie in the great having of weight, the saving of bulk and containers, mil the ability to provide vegetables in ih' l diet in localities where fresh vegetables cannot he grown. The mag".;, tude of the saving of weight may hr appreciated front the fact that the equivalent of approximately I s tons of fresh cabbage. Id tuns of carrot or onion, and six tons of potatoes is contained in one ton of the dehydrated products.

Overseas Work Dehydration of vegetables first came into prominence during the last war. but was not satisfactory owing to failure to recognise the basic principles involved. The industry all but died during the next 20 years or so. and it is only comparatively recently that tin' essential foundations for satisfaetore processing have come to be appreciated. This lias been due to scientific investigations which have revealed that reconstitution of dried vegetables cannot be satisfactorily accomplished unless particular attention is paid to varieties, pro-treatment, temperature and humidity of drying, all of which make all the difference between a product which is tough, lentlierv and unpalatable, and one which, when cooked, cun scarcely be distinguished from fresh material. Research is proceeding in Great liri tain, the United States of America. Canada and Australia, as well as in Xew Zealand, and while commercial production is now being achieved in countries overseas it must be emphasised that further improvements in several directions are still waiting to be effected. 'Pile Xew Zealand Department of Scientific Industrial Ke-

search lias kept in dose touch with overseas work and is posted with the latest developments in both i'oseareh and commercial production. Work in New Zealand was begun in April of last year in response to a request from the Fighting Services to investigate the possibility of producing deli \ drat ed vegetables in the Doni'iiion for their requirements. I’reliminnry investigations were carried out by olliears of the Department of Scientific Industrial Research at its plant eliemistrv laboratory at Palmerston North. The vegetables studied were polatio. cabbage, carrot, parsnip and onion. Successful methods for the processing of these types were worked out. and samples of the tinished products were submitted to and approved by the

three Services. Process Described J'n brief, the process consists of washing, trimming and slicing, shredding or cubing the vegetables, Pillowed bv a short scalding treatment that is necessary to preserve colour, llavour. food \altie and keeping quality, and that also facilitates the re-absorption of water when the vegetables are cooked for use. The vegetables are next spread out on wire-mesh trays .and arc dried in an insulated tunnel through which a strong current of healed, dry air is circulating. Both temperatni and humidity of this air are carefull> controlled to obtain maximum drying rate without overheating the produce. When the drying is completed tbo vegetables have a moisture content ol an|v w.| |, ( . r cent, and they are then immediately packed into moist n relight tinplate cans. Pried vegetables rcadilv reabsorb moisture from the oil' and lienee if becomes absolutely cs-

sont'ial to pack them in airtight containers. otherwise spoilage from the attack's of mould and bacteria quickly results. Commercial Production In view of the success of the initial experiments it was decided to commence full scale commercial production. For this purpose it was neerssarv to develop designs and specifications for a dehydration plant that would be suitable for New Zealand (-(>ii (| i (ion s. Tin* cl l cin idi 1 oiijji n(’<*ri ujl section has in recent years given close at lent ion to a number of plant drying problems. Erection of the plant, the I i r >ot its kind in the Dominion, is now in pro gross and operation will commence in the coming season, it will be capable of processing several thousand tons of fresh vegetables per annum.