347of pasteurization needs to be considered with due caution in view of the deterioration in flavour which usually accompanies high-temperature holding-pasteurization.Addition to the juice of an antioxidant would be desirable if one could be found that would be suitably effective. Ascorbic acid in the concentrations used by the author had some deterrent action but did not completely suppress formation of turbidities.A satisfactory explanation of the phenomena of oxygen absorption by apple juice and subsequent oxidation of the juice in accordance with the evidence presented requires careful consideration. I t must be borne in mind that both oxidizing and reducing enzyme-systems exist in apple juice and that the net degree of oxidation of the juice will depend not only on their relative concentration and activity but also on the relative concentrations of oxygen donator (in this case molecular oxygen) and oxygen acceptor (probably tannin). At ordinary temperatures there is probably some fixation of molecular ozygen on the juice colloids and eventually, through the agency of the apple-juice oxidase system, oxidation of tannin to phlobaphene may occur. The phlobaphene undoubtedly is relatively less soluble than its tannin precursor, a haze develops in the juice, which eventually coagulates as more tannin is oxidized and is thrown out of solution as a sediment in the bottle. When oxidation of tannin by dissolved oxygen is complete and the phlobaphene rendered insoluble, the juice then exhibits strong reducing-properties. Early pre-heat treatment of the juice disturbs the equilibrium of the oxidation-reduction system and although the oxidase is not inactivated at temperatures of 145-150' F. it is possible that such temperatures favour activity of the reducing system.Whether this system is responsible for liberation of some of the ' bound ' oxygen is a matter of conjecture, insufficient information as yet being available to lend support to this hypothesis.I t is hoped that publication of these results will stimulate further research on both deaeration and oxidation and lead eventually to discovery of a suitable method for prevention of oxidation turbidities in apple juice.A description is given of the berry fruit-growing industry in Southern Tasmania. The methods of harvesting and conditions of transportation are described. Analyses of blackcurraits and raspberries, made during the 1948, 1949 and 1950 seasons, are presented with a view to providing information of assistance in determining the amounts of these fruits in pulps and jams.The analytical figures detailed below are the results of a chemical survey extending over the 1948, 1949 and 19jo seasons. The need for composition figures for Tasmanian berry fruits for use in connexion with the analysis of jams has been apparent for some time. In addition
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