Chemistry

In 1942 Miss Margaret Dick of Kraft introduced microbiological assays for niacin and Farrer's studies in the same laboratories over some fifteen years were probably the first systematic application of kinetics in food science.[144] This kind of study, made easy by computers, is now commonplace in the prediction and control of a number of changes in food during heating and refrigeration, but kinetics have many other applications as, for example, in the valuable work on cheese starters carried out by Hall and Linklater in the University of New South Wales.[145] More important, because of its generality, is the recent work of Ratkowsky et al in CSIRO and the University of Tasmania .[146] Many microbiologists have attempted to apply chemical kinetics to bacterial growth by equating the latter to chemical reactions but Ratkowsky and his co-workers have pointed out the serious limitations in the modified relationship used and have shown that the desired linear relationship in the Arrhenius equation exists if, not the growth rate, but the square root of the growth rate is used. This work has many applications and has attracted a lot of attention. Of even greater importance was W. J. Scott's application of simple solution theory to microbial growth (qv. ).[147]

The 1940s saw the laying overseas of the foundations of modern chromatography which at one stroke made possible the detection and measurement in food of a great many substances hitherto unable to be separated, measured or even recognized. Paper chromatography for dye separation and the separation and identification of amino acids, for example, was quickly used in Australian government and industry laboratories in the forties, and then gas/liquid chromatography was taken up eagerly in the fifties. Its impact on food technology was twofold. Firstly, it made the detection and measurement of additives and contaminants very much easier. Secondly, it opened up undreamed of opportunities for studying the chemistry of flavours, both good and bad, and their production in foods and, of course, for the formulation of vastly improved flavours for the industry.

In 1953 the National Health and Medical Research Council (NHMRC) in Canberra set up a Food Additives Committee (FAD) to advise on all aspects of additives and contaminants in relation to Australian food regulations. Australia was thus one of the first countries to take such a step and the committee adopted a comprehensive set of principles some four years before the Joint Expert Committee on Food Additives (JECFA) of WHO/FAO in Rome did the same.[148] FAD's first recommendation was for the elimination of all fat soluble colours from food. The two industry scientists on FAD, on the evidence, agreed but the decision took industry by surprise and there was resistence. However, the modus operandi of FAD as an expert committee acting on the scientific and technological evidence of safety and need, respectively, was rapidly established. There was still argument at times on the interpretation of the evidence but the subsequent inclusion on FAD of toxicologists ensured its smooth operation.

Australian Academy of Technological Sciences and Engineering