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An analysis of the organic acid constituents of tomato juice was prompted by an investigation on the effect of these acids on growth of Racillus coagulans var. thernzoacidurans, Rice and Pederson (17, la),The ogaiiic acids in tomatoes have been fairly well established. Nelson (16) and Borntraeger ( 4 ) found citric and malic acids but no tartaric, oxalic, succinic, lactic o r isocitric acid. Hartmann and Hillig (7) reported the presence of 0.47% citric acid, and 0.05% malic acid. More recently, Kohman (11) and Andrews and Viser (1) have found oxalic acid a t a concentration of 0.01% or less. Bulen et al. ( 5 ) , employing a partition chromatographic technique, found aconitic, lactic, acetic and formic acids, in addition t o citric and malic acids.Thus one might expect to encounter these acids in tomato juice, Hillig (8) and Hillig and Ramsey (9) found 0.0016 to 0.0039% acetic acid and 0 to 0.003% lactic acid in tomato juice.A partition chromatographic procedure was adopted f o r the analysis of the organic acids in the various lots of tomato juice to be used in the study of the growth of Bacillus coagulans. This method was selected since it would make possible the determination of the acids, both qualitatively and quantitatively, from a small amount of sample in a short time and with the use of relatively simple apparatus.Partition chromatography was developed by Martin and Synge (13). It was first employed for the separation of organic acids by Isherwood ( l o ) , who determined the organic acids in several fruits, including apples and strawberries. Marshall et d. (12) employed a similar technique for the determination of organic acids in animal tissue. Marvel and Rands ( 1 4 ) used this procedure to separate organic acids in a determination of the chemical constitution of organic polymers.The silicic acid column, as used by Marvel and Rands ( 1 4 ) and Bulen et al. (.5), was employed for the present determination, with modifications in the method of preparation of the sample, the concentration of sulfuric acid in the aqueous phase, and the solvent schedule.

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The "flat sour" organism, Bacillus thermoacidurans Berry (1933), is important to the canning industry because it is one of the few sporeforming organisms capable of growing in an acid food product, such as tomato juice. The seriousness of this type of spoilage lies in the fact that its occurrence is sporadic and as yet unpredictable. Furthermore, because little or no gas is produced to reduce the vacuum in the container, detection of the spoilage is impossible without first opening the container. The organism, a heat-resistant, sporeforming mesophile, was described by Berry (1933), who noted its tolerance to acid. In general, he observed that it produced only moderate growth in culture media and produced no gas in carbohydrate media, although acid was produced in a variety of sugars. Smith, Gordon, and Clark (1946) demonstrated from comparative cultural studies that Bacillus thermoacidurans Berry and the more recently described Bacillus dextrolacticus Anderson and Werkman (1940) are identical with Bacillus coagulans Hammer (1915), described some time before either of these names was proposed. The identity of these three organisms is also accepted by Breed, Murray, and Hitchens (1948). Although Bacillus coagulans is therefore the correct name for the species here discussed, so far as is shown by the studies made thus far, it has proved convenient to use the name Bacillus thermoacidurans in this paper for those cultures that were isolated from tomato products. The name Bacillus coagulans is used for the culture isolated by Hamer from evaporated milk. Although little work has been done on the physiology of Bacillus thermoacidurans, several papers of practical importance dealing with control measures designed to destroy the resistant spore have been presented. The organism is acidtolerant to a degree. Pederson and Becker (1949) found that although the vegetative cells of some strains could grow in tomato juice of pH 4.15 to 4.25 the heated spores could not germinate and grow in tomato juices that had been adjusted to a pH lower than 4.32. During the normal processing of juice the non-heat-resistant vegetative cells are readily destroyed. Further physiological studies have been undertaken to learn more of the nature of the organism in the hope of developing better measures for controlling its growth in foods. Cultures studies. The 23 cultures of Bacillus thermoacidurans and 1 culture of Bacillus coagulans studied included cultures isolated in the laboratory and others received from the laboratories of the National Canners' Association, Continental Can Company, American Can Company, and the American Type 1