Pasteurization and Hygiene

In the early 1890s Wilson visited Europe to study 'pasteurized and fermentized' butter and in his report for 1893-4, he forecast that if pasteurization became general, there would be no need for boric acid. He urged the industry to adopt it and within two or three years appointed Robert Crowe as an instructor in the use of the pasteurizer. Pasteurization, the controlled heat treatment of perishable liquids to kill pathogenic micro-organisms, was invented by Louis Pasteur in the 1860s. It was used commercially in Europe in the eighties and shortly after was taken up in America, where its demonstrated value in saving infant lives led to its adoption for milk supplied to several cities. Its use in Australia was not general until after the Second World War, when the major advances in dairy technology in this country occurred.

Even though the Victorian Health Act of 1890, for example, dealt with the construction and sanitation of dairies, a major cause of the quality crisis referred to above was the almost universal ignorance of hygiene in the dairy, of cleaning and of sanitizing cleaned equipment. Even in the 1930s the Victorian Superintendent of Dairying found it necessary to insist on the need both to sterilize equipment after cleaning and to ensure that the water used was in fact boiling. Sanitation problems were exacerbated by the introduction at the turn of the century of the first milking machines, but the wholesale use of this equipment was delayed until the late thirties following the easing of the economic depression and the general availability of electricity.

In the 1870s Thomas Mort used refrigeration to transport city milk supplies but refrigeration was slow in coming to the industry. Some dairies used it before the First World War and many farmers used water coolers. As late as the early 1920s, the quality of the milk supplied to both Melbourne and Sydney was causing concern and it was only in 1922 that dairymen supplying Melbourne, for example, were required to cool their milk. In this same period, herd testing and the regular chemical and microbiological examination of milk supplies began. Bottled milk appeared in 1923, but was only slowly accepted. If properly pasteurized and handled, it was far safer than the delivery of loose milk, but it was, and still is, very vulnerable to light.

Condensed Milk

On 4 September 1882, a condensery began to produce sweetened condensed milk in the dairy products plant of the Melbourne Milk Supply Company at Romsey in Victoria. The product failed, possibly because of the general lack of knowledge of microbiology at that time. In 1886, the factory turned to concentrated milk only to fall foul of the continuing problem of seasonality of the milk supply. In 1890, the Bacchus Marsh Concentrated Milk Company was established and within a few years began to export. Production of processed milk expanded during the First World War but fell away in the succeeding twenty years.

Australian Academy of Technological Sciences and Engineering