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Non-washing of Butter. —Continuing these experiments, with poor-quality cream it was found that the omission of wash and chill water made a difference, but it amounted to only one-fifth of a point in average grading score. Land-cress Taint in Cream and Butter.—lt has been shown that when cress taint has been developed in cream by heating the cream to boiling point for thirty minutes, the tainting substance can be destroyed by the addition of chlorine solutions, and investigations were made to determine whether chlorine had any deleterious effects on butter quality. Hypochlorite addition to give up to 200 p.p.m. available chlorine in cream free from cress-taint had no appreciable effect on quality. These investigations are continuing. Cream, from Returned Milk.—Butter frequently develops a tallowy flavour when made from cream obtained by separating returned bottled milk of town supplies, and experiments have shown that a 10 per cent, inclusion of this cream in a churning gives a definite tallowy flavour in the butter after four months' storage, whilst 5 per cent, will cause some deterioration of flavour. It appears that the action of sunlight on the milk initiates oxidation of the fat. Effect of Temperature Trmtment of Cream on Body of Butter. —It has been found that if cream is held at 60°f. overnight and cooled just before churning, the butter is very much softer than that obtained by the usual practice of cooling cream to churning temperature and holding at this temperature overnight. The more-plastic butter produced from cream held at a high temperature is normal in other respects, but there is an increase of fat loss during churning. First cooling the cream to about 45°f., then warming and holding overnight at 6Q°f., and cooling before churning avoided the increase in fat loss. Attempts to increase the firmness of butter by holding cream at a temperature of 35°f. before churning were unsuccessful. Alfa Continuous Buttermaking Process.—Experiments showed that " heavy " cream from vacreated cream was always higher in moisture content than that from flash-pasteurized cream. It was • thus made clear that difficulties of moisture control encountered with the Alfa process were largely due to the properties of vacreator-treated cream. Casein. —The Institute has co-operated in the formulation of standard specifications for water paints, and has participated in trials of paints for use on interior walls of dairy factories. Starters for Cheese-manufacture. —The Institute has continued to act as the main source of supply of starters to cheese-factories throughout New Zealand, and the reputation of single-strain starters has resulted in requests for the supply of cultures to other countries. An endeavour is being made to find eight completely unrelated cultures, which would enable managers to use two cultures each day in a four-day rotation. Only seven cultures have so far survived the test of commercial use, but no doubt others will be disclosed. A new phage has been encountered that shows very unusual action, but it is still under investigation. Cheese-manufacture. —Experiments on the relative effects of various procedures on the expulsion of moisture from cheese curd during manufacture were continued, and it has been found that a significant difference in moisture content between the final control and experimental cheeses is most readily brought about by variations in the size of cut, the amount of dry-stirring, and the proportion of salt added to the curd. The speed of agitation has little or no effect, while cooking temperature has to be varied by at least 4°f. before

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