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London Branch of the Primary Products Marketing Department, . nd much of their time is devoted to special inspections and the consideration of claims of purchasers in reference to alleged faulty produce. In this respect one pleasing feature is a decrease in the number of complaints relating to foreign matter in New Zealand butter and cheese. While, however, the position has improved, there is still cause for concern, and supervision has been tightened in an endeavour to bring about greater safeguards in the dairy factories of this Dominion. In addition to his regular duties, Mr. Taylor is frequently called upon to act in a special capacity on various committees and at various conferences relating to dairy industry matters. He was, for instance, an official representative of New Zealand at the Eleventh World's Dairy Congress held in Berlin in August of last year. Mr. Taylor filled this responsible post with distinction and, apart from the personal contacts which he made while in Germany and the educational benefit of his experiences, his report to the New Zealand Government is a valuable document for present and future reference. Mr. Taylor is also a member of the British Standards Institute, and his work on the committee of this organization has taken him to the Continent of Europe on at least one occasion during the year. The London inspection service constitutes the final link in he chain of Government supervision of New Zealand's great dairy industry, and renders invaluable service in the direction of enabling a reliable guide to the consumer's tastes and xequirements. Dairy Laboratory, Wallaceville. It is the aim of the Dairy Division's Laboratory at Wallaceville to provide to the instructional and grading staff a service for the carrying-out of routine tests upon samples of dairy-produce in order to assist the industry throughout the Dominion. During the past year the number of samples dealt with has again increased considerably, and a total of nearly three thousand have been dealt with. This represents an increase not far short of 50 per cent., and, in addition, several hundred milk and cream samples were submitted to various tests in dairy factories. Of the total, nearly two thousand consisted of butter samples for bacteriological tests. For some six years past the Laboratory has endeavoured, especially by the testing of starters for bacterial contamination, to improve the conditions under which starters for cheesemaking are kept in dairy factories. During the past season nearly four hundred starter samples were tested for bacterial contamination, this number being a little short of double the number dealt with the previous season. A fair proportion of these starters had originally been supplied from this Laboratory by request of the factories. The results of these tests indicate that progress is being made in the handling of starters under factory conditions. The number of contaminated samples, however, indicates the need for increased efforts to improve the position. Besides starters for cheesemaking, butter-starters continue to receive a small amount of attention. The Laboratory has endeavoured to keep in touch with the latest developments connected with milk-grading. For this purpose a small number of trials have been carried out with a new dye, resazurin, which is said to possess certain advantages over methylene blue. For the purpose of creamgrading resazurin has given very promising results indeed, and the test has been found to correlate satisfactorily with cream-grading by the ordinary method. Much more work requires to be done to ascertain the possibilities of the test, but present indications are that it is more promising than any other bacterial test which has been tried for the purpose. As in the previous season, bacteriological tests upon butter from the grading-stores have constituted a major portion of the work of the Laboratory. Early in the season arrangements were made for Auckland butters to be tested in the grading-store at Auckland, and in their place samples have been procured regularly from New Plymouth by means of an ice-box to check changes during transit. In reporting the results of these tests a higher standard has been set than in previous seasons. While some factories seem to have no difficulty in regularly making butter with a minimum of bacterial contamination others fail to reach the desired standard. Reports have been received which indicate that where unduly large numbers of bacteria have been found some pa.rt of the plant has been discovered to be in an unsanitary condition. These tests are of particular value in enabling such defects to be discovered usually before the trouble has become acute enough to affect the grading of the butter. In following up these tests in some factories by more detailed tests for the source of contamination it has been possible to find the parts of the plant which are particularly responsible for the trouble. This work has indicated the desirability of devising improved methods for the cleaning of the large refrigerated cream-vats. As in past seasons, the Laboratory has endeavoured to assist in the procuring of improved factory water-supplies, attention being given principally to the waters used for butter-washing purposes. The Instructors have assisted in making a survey of the water-supplies of butter-factories throughout the Dominion, and the information so collected has enabled first attention to be given to those cases where the water-supply may be of doubtful quality. The number of water samples dealt with is appreciably greater than those tested in the previous season, but many more factories still remain to receive attention. In addition to bacteriological tests, chemical tests are also carried out so as to enable advice to be given about the treatment of the water. The principal chemical work carried on in the Laboratory has been the testing of butter for metallic contamination. The improved methods devised for the purpose have been applied during the past year, especially to the testing of samples for copper content. In districts where a considerable, amount of stainless-steel equipment has been introduced during recent years the copper content is usually satisfactorily low. In other districts, however, a number of factories are still making butter with a copper content which is likely to adversely affect its keeping-quality. Whey butter often has too much copper. In many cases this might be reduced to a more reasonable figure if the plant were kept in better condition.

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