In Japan, no preservatives are permitted by the Food Sanitary Law for “Carbonated beverages” and as a result, we can't expect that so-called natural juice-type carbonated beverages should have effect of inhibiting spoilage-organisms, unless they are carbonated over the range of fresh taste. Far from that, generally, they are favourable medium for the growth of spoilage-organisms.
We have researched into differences of shelf-life properties among 5% natural juice containing samples, 10% natural juice containing sample, and no natural juice containing sample, and about the effect of adding sodium benzoate (BA-Na). The result is that 5% and 10% natural juice contained samples are deteriorated shortly and the addition of BA-Na (0.05% by weight in each of them) inhibits perfectly the growth of spoilage-organisms.

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There has been no report about the lytic action of lysozyme on germinale spores, vgetative cells or spore-forming organisms incubated for a long time. In this paper, the lytic action of lysozyme is reported on spores and vegetative cells of Bacillus subtilis which is one of the food contaminating microorganisms.
In this experiment, the effect of lysozyme of various concentration such as 0.00125, 0.0025, 0.005, 0.01, 0.0125, 0.025, 0.05, 0.1 and 0.2% was examined by using spores and vegetative cells which were cultured for 3 hours or 48 hours in a pepton water. The results obtained are as follows.
1) In all the concentrations of lysozyme except for 0.00125% concentration, spores were inhibited to germinate, and in a 0.00125% lysozyme solution very slight germination was observed. The lytic activity of lysozyme to spores, however, must be determined by detecting the liberation of some chemical compositions from spore.
2) Lysozyme exhibited a fairly high lytic activity on vegetative cells in 0.01, 0.005 and 0.0025% lysozyme concentrations respectively and this activity became lower in such concentration order as 0.025, 0.05, 0.1, 0.2 and 0.00125%.
3) Bacterial counts showed similar tendency to results of transmittance values in 1, 24, 48 and 72 hours after incubation.

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In order to study conditions to retain the effect of vitamin or antioxidant action, substances mentioned in the heading were examined as to how their stabilities were affected by sodium hexametaphosphate coexisting with other food additives and food components in water containig 32μg% Cu²⁺.
1. Sodium hexametaphosphate had remarkable stabilizing effect on ascorbic acid and its sodium salt, and had the maximum effect within a range of 8 to 30mg%concentration.
2. The effect of coexisting other food additives and food components with sodium hexametaphosphate on the stabilities of the vitamin and its sodium salt could be grouped into four types as follows:
a) Residual rates of ascorbic acid and its sodium salt went on decreasingly and their differences were remarkable when certain food additives (below mentioned) coexisted with sodium hexametaphosphate.
Name of the food additives: saccharin sodium, sodium cyclamate.
b) Residual rates of ascorbic acid and its sodium salt went on decreasingly and their differences were slight when food additives described later coexisted sodium hexametaphosphate.
Name of the food additives: sodium benzoate, sodium alginate, sodium carboxymethyl-cellulose.
c) Residual rates of ascorbic acid and its sodium salt were at the the lowest level at a certain concentration of food additives which were added to the vitamin solution with sodium hexametaphosphate.
Name of the food additives: sodium tripolyphosphate, sodium dehydroacetate, glycine, sodium glutamate, soluble starch, sodium chloride.
d) Good effect of sodium hexametaphosphate on the vitamin-stabilizing ability was found by the coexistence of below described food additives.
Name of the food additives: citric acid, sucrose, sorbitol, propylene glycol.
As observed above, although sodium hexametaphosphate alone had a good stabilizing abilizing ability, the coexistence of other food additives and food components reduced its protective effect against the decomposition of ascorbic acid and its sodium salt. The mixture of citric acid and sodium hexametaphosphate showed a extremely good effect on stabilizing ascorbic acid and its sodium salt.

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Since the authors have confirmed that some vegetable oils contain detectable amounts of cholesterol, it would not be appropriate to determine the presence of animal oil in margarine only with the existence of cholesterol, unless extremely a large portion of animal fats were occluded.
Secondly, the authors found that the composition of fatty acids in margarine is highly characteristic in respect to its constituent. That is, the vegetable oils hardly contain fatty acids having over 20 carbons, carbon odd-nnumbered acids and C_{16: 1} acids, on the other hand, beef tallow contains considerable amounts of carbon odd-numbered acids and C_{16: 1} acids. Besides, oils of fish or whale origins are rich in fatty acids with over 20 carbons, Furthermore, hydrogenated vegetable oils contain fair amounts of C_{18: 1} trans acids.
In conclusion, with consideration on the pattenn of these components, it would be possible to judge the animal or vegetable nature of margarine, as well as sorts of oils as components in margarine to some extent.

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The oxidation of methyl linolenate in diffused daylight, and under UV ray γ ray was studied by pursuing changes of its thiobarbituric acid (TBA) value, peroxide value, quantity of conjugated diene, carbonyl value, and rate of weight increase. As a result, it was found that the tendency of changes in TBA value and cardonyi value were similar, and that UV ray did not only accelerate to produce the first oxidative product[s]of methyl linolenate, but did more intensely to decompose this product[s], which influenced TBA value and carbonyl value after UV treatment.
Three pigments were always identified from the reaction products of oxidized methyl linolenate and TBA by chromatography without regard to the methods and various stages of oxidation. The pigment 1, λ max. 454mμ, seemed to be similar to n-vaieraldehyde-TBA condensation product from the viewpoint of chromatographic behaviours and spectro-photometric character, which was presumed as one of substances disturbing TBA value. The pigment 2, λmax. 510mμ, was found to be very small in quantity amoag the reaction mixtures. The pigment 3, λmax. 532mμ, was identified as the object of TBA value and a malonaldehyde-TBA condensation product.

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This paper dealt with identification and cardinal growth temperatures on Psychrophilic anaerobes found in frozen fish-internal organs as: Ocean bonito, Yellow-tail, Cod-fish, Pollack, Flat-fish, Horse-mackerel, Sciaena schlegellii, further, frozen Shrimps were also taken for this experiment. Those samples were purchased at fish stores in Tokyo, and collected from a Deep-sea-fishing-boat.
A total of 42 pure cultures of bacteria was isolated from the samples. Of the cultures, 7 were two species of a genus Clostridium, 8 were one species of a genus Propionibacterium, 16 were two species of a genus Leuconostoc, and 11 were Gram positive, nonsporeforming, long curved rods.
The optimal growth temperatures of Clostridia ranged from 25 to 35°C, but grew well for 8 days at 5°C. The optimal growth temperatures of Propionibacterium, Leuconostoc and 11 unidentlfied strains ranged from 20 to 25°C, and also grew well for 8 days at 0°C.
The ecological aspects and food sanitary views of the isolates were briefiy disccussed.

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Nitrate, when contained in canned acid products, is known to cause severe corrosion on the internal tin surface of container, accompanied by rapid dissolving of tin which migrates into the contents. The present paper dealt with results obtained by a test pack experiment and a model experiment, and mechanism of nitrate action to dissolve tin was discussed.
(1) Apositive logarithmic relationships were observed between initial nitrate amounts in the can and formation of ammonia. The tin-dissolving rate was found to be proportional to the former.
(2) Mechanism of the nitrate action was studied with a model pack experiment, in the event of which a model canned drink containing nitrite or nitrate was kept in the absence of oxygen. It was found that detinning by nitrite was rapid with the rapid decrease of nitrite, whereas, in the case of nitrate, both detimling and nitrate reduction were very slow.
From these results, it was concluded that the nitrate reduction to nitrite was a ratelimiting step in the over-all reaction, and nitrite acted in the canned acid products as a strong oxidizing agent against tin, while itself rapidly being further reduced to ammonia. It was assumed that when bivalent tin, Sn (II), a strong reducing agent, was formed by the action of oxygen, nitrate present was reduced to nitrite which readily attacks metallic tin to form bivalent tin, and, thus, the reaction proceeded in such a manner as a chain reaction. Oxygen must, therefore, be playing such a role as a “trigger” in the over-all reaction.

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Bleaching treatment of fish jelly products with hydrogen peroxide (H₂O₂) has been widely practiced after heat processing of these products. And, in addition, excessive uses of H₂O₂ by the industry frequently draws the attention of public health authorities and consequently raises an urgent need for survey of residual amounts of H₂O₂ in the products to control whether the treatments are adequately performed in the commercial preparations.
A modification of H₂O₂ determination method was firstly proposed in this paper, since a simple iodometry using sodium thiosulfate (Na₂S₂O₃) titration is apt to give some erroneous results in these particular products to which potassium hypobromide (KBrO₃) may have been added as a jelly texture improver.
Repeated experiments indicated that an use of catalase preparation to the aqueous extract of “Kamaboko” products before iodometric titration was found feasible to eliminate the effect of KBrO₃, where the titers of Na₃S₂O₃ represented only the concentration of hypobromide. Therefore, the difference in the titers between nontreated extract and catalasetreated one can be used as the basis of true H₂O₂ determination.
Most samples of “Kamaboko” and “Chikuwa” (baked bamboo-shaped products) purchased from Tokyo Central Fish Wholesale Market showed a small or negligible quantity of H₂O₂, except the samples manufactured in particular regions which contained considerable amounts of the chemical. “Hanpen” and “Naruto-maki” products examined revealed comparatively higher content of H₂O₂ and taste panels noted some off-flavour possibly due to the use of H₂O₂.
A sharp decrease of residual H₂O₂ was observed in the experimentally prepared “Kamaboko” during a storage period of several days after the bleaching treatment. The disappearance rate of H₂O₂ slackened thereafter for about ten days, when certain amounts of H₂O₂ still remained in the “Kamaboko”. And, higher residual content was noticed when either high H₂O₂ concentration or long time dipping in the bleaching solution was employed.
It was concluded from these examinations that a large amount of residual H₂O₂ in commercial fish jelly products should be attributed to the over-use of H₂O₂ and a reduced cocentration of H₂O₂ or shortened time of immersion in the bleaching solution was suggested.

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A method for recovering preservatives in foods by the steam distillation under reduced pressure was studied. The outline of procedure is as follows.
1) In the case of samples containing dehydroacetic acid (DHA), sorbic acid (SOA), benzoic acid (BA) and salicylic acid (SA), the distillation was conducted under 90mmHg of pressure and at 50°C (water bath temperature: about 70°C), after addition of a 10ml of portion of 10% citric acid, suitable amouts of water, 20g of NaCl and 50g of MgSO₄·7H₂O, and adjusting pH to 2.0-2.5. 240ml of distillate was retained.
2) In the case of samples containing butyl p-hydroxy-hydroxy benzoate (POBA-Bu), the distillation was carried out at about 80°C (water bath temperature: about 95°C), and under the same low pressure, after addition of suitable amouts of water, 20g of NaCl, and adjusting pH to 3.0, and then 490ml of distillate was obtained.
By the application of this method, the preservatives in foods could be recovered rapidly, and sucrose, in particular, among other ingredients in foods were almost never decomposed during the process.

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There have been few reports in which Japanese cakes were examined for microbiological contamination from the standpoint of food hygiene. The present study was aimed at standardizing microbiological sanitary indices for Japanese cakes based on survey in which these cakes were bacteriologically examined.
The frequency of coliform-group-positive samples was 44.0%, while that of samples in which more than 100 colonies per gram could be detected was 84.0% for viable counts, 50.0% for Staphylococci, 46.0% for yeasts or 62.0% for molds.
There was a tendency that the more the viable counts, the more Staphylococci and yeasts counts as well as the detection ratio of coliform group. No coliform group organisms could be detected in samples with viable counts of less than 100 colonies per gram.
From these results, it will be proposed that the existence of coliform group organisms and viable counts of more than 100 colonies per gram of samples are regarded as two most critical sanitary indices for Japanese cakes.

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