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was pasteurized under conditions which ensured destruction of any bacteriophage present. Incorporation of this cream increased the output .of cheese by 1-2 times the weight of fat, but as the cream contained approximately only 5 per cent, of the total fat contained in the milk from which the cheese was made, the fat content of the was not greatly increased. The experiments showed the absolute necessity for insisting upon adequate pasteurization of the whey cream. Starter Studies.—Much work continues to be done on problems designed to reduce the damage done through bacteriophage entry into both single-strain and mixed-strain starters used in cheese-factories. Starters can be kept vigorous for long periods when these are prepared in isolated rooms fitted with air-filters to prevent potential contamination from the atmosphere in the vicinity of cheese-factories. The past year's work has revealed that cheese milk can become infected with bacteriophage to an extent that will affect the quality of the cheese even when an active and phage-free starter is used. This difficulty can only be overcome by scrupulous treatment of cheesemaking plant and by properly washing suppliers' cans used in the transport of whey. Control of Cheese-mites.—ln collaboration with the Entomology Division of the Plant Research Bureau, studies of the prevention of mite growth in cheese have shown that ammonia, though destructive to the mites, is not an effective fumigant in large stores, where methyl bromide used at the rate of 4 lb. per 1,000 cubic feet of storage space is more toxic to the insect and not detrimental to the flavour of treated cheese. Milk-production Studies. —The studies of the influence of different pasture diets on stock health and the yield and composition of milk produced thereon have been continued. As yet, no outstanding differences attributable to different swards have been observed. Weekly examinations of milk from the Institute's dairy herd have been made by the Wallaceville Veterinary Laboratory, and after three years of freedom from trouble some cows became infected with mastitis, while others produced milk ol high leucocyte count, though not infected. FOOD PRESERVATION AND TRANSPORT ADVISORY COMMITTEE Personnel. —Professor H. G. Denham (Chairman), Dr. J. C. Andrews, Mr. A. H. Cockayne, Mr. C. A. Duncan, Mr. F. W. Grainger, Dr. E. Marsden, Mr. G. M. Pottinger, Professor W. Riddett, and Mr. F. J. A. Brogan (Secretary). The following is a brief review of the activities under the general .supervision of the Committee, which held four meetings during the year. Dry Butterfat.—Aitev the Dairy Research Institute had produced for export to Great Britain about 1,400 tons of dry fat from, whey and second-grade butters, commercial production ceased there and was taken up by the dry-butterfat plant of the Internal Marketing Division at Auckland at the end of July. Dr. F. H. McDowall, Chief Chemist, visited Australia to study methods of processing dry butterfat and other dairy products for wartime use. The' Institute is now concentrating on research problems relating particularly to the improvement of keeping .quality of dry butterfat and to the manufacture of dry-butterfat milk-powder spreads, and butterfat preparations of high melting-point which will withstand tropical temperature conditions. The experiments on the high-melting fats are being conducted at the request of, and in close collaboration with, the armed Services. Cheese. —Experiments are being made on the modification of cheese for Army rations to enable it to withstand tropical temperatures without loss of body and palatability. Fibre-board Butter-boxes.—Full reports from Great Britain on experimental shipments of butter in fibre-board boxes which were arranged by the Committee were most satisfactoiy, and further larger consignments are to be forwarded to Great Britain. Butter-wrapping Experiments.—Reports from Great Britain on experimental shipments of butter to determine the relative value of Pliofilm and Pliofilm plus parchment for wrapping butter forwarded in chilled cargo with cheese were not decisive as regards the merits of these two methods. Neither method, however, was as good as sending the butter in the form of fat. Dried Meat.—At the request of the British Ministry of Food, experiments were arranged on the use of a special coating for dried-meat blocks to render them moisture-proof. Investigations were also made on methods of increasing the fat content of dried meat. Dr. J. C. Andrews visited Australia to investigate methods of dried-meat production and to consult with Dr. J. Vickery, Director of the Division of Food Preservation and Transport, Council for Scientific and Industrial Research. The large-scale production of dried meat to meet the Government contracts is now under the supervision of the Department of Agriculture, to whom Dr. J. C. Andrews is technical adviser, and a commercial plant is in course of erection. Dried Vegetables. —With information obtained from Great Britain, the United States of America, and Australia, and following research and developmental work by the Fruit Research Officer, the Plant Chemistry Laboratory, Palmerston North, and the Chemical Engineering Section of the Dominion Laboratory, processes and plant for the local production of dehydrated vegetables were worked out and brought to the stage of commercial production. The first full-scale commercial vegetable-dehydration plant is now being installed at the Wattie Canneries, Hastings. Army Rations—Much of the work initiated and developed by the Committee on the processing of foodstuffs for storage and transport under war conditions is finding important applications in the preparation of special rations for the armed Services.

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