258 Agricultural Gazette of X.S.W. [April 3. 1920. 



Such a loss would be cut out and reco\ered by the building of a new factory, 

 situated in a more convenient and sanitarj' position, on up-to-date lines. 

 The cost of building and equipping at the present time may seem hard to 

 bear, but the ultimate cost is less than the loss, year in and year out, of 

 several shillings per cwt. on the selling price of the butter mtmufactured. 

 Lifting the quality of the butter by a few points means obtaining bigger 

 returns. Take, for instance, a factory with an output of 35 tons of butter 

 per week. If an extra 3s. per cwt. is obtained, it means over £100 per 

 week extra revenue, and it does not take many years at that rate to pay 

 for a modern, well-equipped factory. This lesson has been proved and 

 demonstrated by the Manning River Co-operative Dairy Company. The 

 tjuality of the butter now put on the market by that company is so improved 

 as to be incomparable with that manufactured under the old conditions. Tt 

 was proved at the same time that a saving of some ,£14 per week in labour 

 was effected. In the modern, well-equipped factory nine men, working- 

 ordinary time, handled a much greater output than was done under the old 

 conditions with thirteen men, often earning oyertirae rates of paj'. 



The manufacture of butter may be described as a fermentative industry, 

 the flavour being due co the absorption by the fat of certain aromatic 

 substances produced during the acid fermentation of the lactose of the milk 

 or cream by Baclerium lactis acidi and related organisms. Most of the 

 abnormal flavours are due to the replacement of the desirable acid-forming 

 bacteria with other types of micro-organisms. Henc^, to conti-ol the flavour 

 of the butter the butter-maker must control the bacteria in the cream that 

 cause the ripening. 



As it is freshly drawn from the normal udder of the healthy cow, milk 

 contains bacteria in greater or lesser nvmibers, the initial contamination 

 taking place in the milk cistern and larger milk ducts of the udder. These 

 organisms appear to cause no change in the market value of th(> milk, or in 

 the persons drinking the milk. If, however, the cow is suti'ering from disease 

 in the udder, such as tuberculosis, mammitis or other inflammatory ta-ouble, 

 the milk maj' contain many millions of the specific bacteria at the time when 

 it is drawn. The extent of all subsequent contamination is dependent upon . 

 the manner and care with which the milk is produced and handled. The 

 atmosphere, utensils, milking machines, and the milkers themselves add 

 many bacteria ; their future development is largely dependent upon the 

 temperature at which the milk is kept. 



Most micro-organisms find in milk an ideal culture medium for their 

 growth. The food elements such as protein and milk sugar, being in liquifl 

 form, are most easily attacked, and it is the breaking down of these, by 

 Ijacterial enzymes formed, which cause most of the undesirable changes. 

 The cream of milk, whether separated by gravity or by means of the 

 s(parator, will contain considerably more bacteria per unit volume than the 

 milk. The tiny fat globules passing through the milk serum carry 

 mechanically many l^acteria of the milk into the cream, which on arrival 

 at the butter factory and often oidy a few hours old, is in many cases 



