Chemistry (continued)

Chromatography was rapidly adopted by CSIRO and industry for flavour studies. New information has been obtained and the causes of taints in products as diverse as dairy products, sea food and mayonnaise have been identified and corrected with obvious commercial benefits.[150]

Most of the ancillary food ingredients used in Australia are imported, but there has been some local manufacture since the war, and one major Australian technological achievement in flavour was made possible by advances in the understanding of the chemistry of the specific flavour substances involved. Dissatisfaction with the performance of hops in the brewing industry led Carlton and United Breweries to establish in 1950 a hop breeding programme designed to produce a plant more amenable to local climatic conditions and containing increased concentrations of hop resins and alpha-acids.[151] Success came rapidly and the resulting variety, Pride of Ringwood, now (1986) accounts for more than 90 per cent of the hops grown in Australia. In 1959 the company chemists began a basic research programme on the chemistry of the major flavouring constituents of this and other varieties and from it has flowed a series of advances in the manufacture of hop extracts suitable for flavouring beer.

At first the extractant was trichlorethylene but regulatory concern generally over traces of solvents in foods, itself a product of the new analytical methods already referred to, led the company to look further and the work culminated in 1980 with the commissioning of a plant for the extraction of hops with liquid carbon dioxide. This was a world first and was achieved solely by the company's own scientists and technologists; there was nothing to guide them. The results of this work have been a highly successful new variety of hop, a series of extraction products resulting from a sound chemical study of the raw material and imaginative innovation, a completely new residue-free method for extracting hops, and the more efficient and controlled flavouring of beer.

A by-product of brewing is the spent yeast, which is of no further use to the brewer but which is ideal for the manufacture of yeast extract by autolysis. Modern chemical methods were used in industry in the 1970s to study its flavour components, with results which were usefully applied.[152]

Flavour work of a different kind, the prevention of an unwanted one, was that on orange juice. When war broke out in 1939, there was no Australian fruit juice industry and the Americans wanted orange juice. With CSIR's help an industry emerged and has flourished. One of the chemical challenges was the identification and control of the bitter principle of navel orange juice, limonin. J. F. Kefford and B. V. Chandler in CSIR identified a number of parameters governing its appearance and the latter made contributions to the elucidation of its formula, its analytical determination and its removal from orange juice.[153]

Australian Academy of Technological Sciences and Engineering