Application of ascorbic acid 3-phosphate-Mg (AsA phosphate-Mg) to meat products were studied in comparison with sodium ascorbate (AsA-Na). 1) AsA phosphate-Mg was hydrolysed to AsA by acid phosphatase in the water soluble fraction of meats. There was little difference of phosphatase activity in the species of meats such as pork, beef, mutton and horse meat. 2) When AsA phosphate-Mg was used as substrate, acid phosphatase activity in the water soluble fraction of meats was not accelerated by various metallic ion but inhibited slightly by Ba²⁺ and Zn²⁺. Its optimum temperature was approximately 40°C. 3) AsA phosphate-Mg added to meat was almost hydrolysed to AsA in less than 3 days at 5°C. AsA phosphate-Mg had also the same protective effect against the fading of cooked cured meat color with AsA-Na. 4) AsA-Na in the presence of sodium nitrite in the dry curing mixuture was easily decomposed under the condition of the high relative humidities. On the contrary, AsA phosphate-Mg was more stable than AsA-Na.

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Freeze drying products of citrus juice have not been industrialized in Japan. "Puffing" phenomenon is one of problems to be solved.
As the result of an investigation on the freeze drying of citrus juice, the following conclusions were obtained:
Free water to some extent in the citrus juice was necessary for well performed freeze drying. Considerable amount of bound water was contained in concentrated cirtrus juice, which causes puffing phenomenon during freeze drying when it is difficult to evaporate. Freeze drying of concentrated citrus juice of which moisture level is over 50% including free water is possible to perform well. Ice grifting gave the best result for freezing of citrus juice, especially when slow freezing process at comparatively high temp. was employed instead of super cooling at lower temp.

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Lycopene and β-carotene in the solvents as dioxan, n-heptane and aq. Tween-20 were heated in the thermal-death-time tubes at 100, 113, and 130°C to investigate the heat stability by determining the initial velocity of decomposition. The initial decomposition followed the simple equation of reation. β-carotene was more stable than lycopene in each solvent. The velocity of decomposition of these carotenoides was the highest in dioxan followed by Tween-20 and n-heptane in this order.

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Optimum radiation dose for the preservation of bacon for one month of shelf-life at room temperature was investigated by the irradiation with 0.00, 0.25, 0.50, 0.75 and 1.00 Mrad of gamma ray, respectively. The samples irradiated with less than 0.75 Mrad were not kept even for one month. Even in the case of 1.00 Mrad sample, 10⁶/g survivors were detected, indicating that it was not in good hygienic condition for food.
Bacon samples irradiated with low dose (0.5 Mrad) and high dose (5.0 Mrad) were compared. The high-dose sample was kept well apparently much longer with off-flavor by radiation. The off-flavor decreased gradually during the storage period, and disappeared in one month when the bacon was cooked. The low-dose sample was not kept for one month.
In another experiment, 1, 3 and 5 Mrad of irradiation were compared. After 45 days of irradiation, there were only a few survivors (10³/g) detected in the samples irradiated with 3 and 5 Mrad at 15°C. Considerable off-flavor appeared in 5 Mrad sample. A little off-fiavor appeared in 3 Mrad sample, which disappeared about one month after irradiation.
From these results, it was considered that the optimum dose of irradiation of bacon is 3.0 Mrad.

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It is well known that oxidative deterioration of the lipids in the foods is the cause of the development of off flavors during storage. In the present investigation, the models were used by replacing the food with a support of Celite as a structural component. Beef tallow and saury oil as animal fats, safflower oil, rape oil, soybean oil and cotton-seed oil as plant oils, and stearic acid, oleic acid, linoleic acid and linolenic acid as fatty acids were added into the Celite (model food) respectively. Those were stored under different temperatures (30°, 0° and -20°C) for 12 weeks. The course of the oxidation of oil was observed by determining the TBA value and peroxide value.
Subsequently, it was found that the oxidation of saury oil was significantly higher than other oils and that especially in high temperature like 30°C, the oxidation was higher than in lower temperature. Unsaturated fatty acids were unstable even in the low temperature as -20°C. Furthermore, fatty acids of higher degree of unsaturation were oxidized to a great extent.

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The models for experiment were prepared replacing the food with a support of Celite as a structural component, impregnating this with glucose, sucrose, soluble starch, glycine, monosodium glutamate, pepton and ovalbumin at the concentration of 0.1, 1.0, 5.0 and 10.0% to the oil. Effects of the added components on the TBA value and the change of the weight were investigated at 30°C.
Subsequently it was found that glucose, sucrose and soluble starch had no effect at all even in the higher concentration. While, glycine, monosodium glutamate, peptone and ovalbumin had a protective effect from the oxidation. Such a protective effect was remarkable in the high concentration in the range of 0.1 to 5.0%. When the nitrogenous compounds were used, a yellowish color and the uncomfortable smell, which was different from rancidity-smell caused by linoleic acid oxidation, were developed and they were more remarkable in the higher concentration than 5%.

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No offcial quality datum of the commercial agar manufrctured in Nagano has ever been published. With the purpose to establish the more scientific quality evaluation of the commercial agar, in the first experimental work, the yearly distributions of both gel strength (jelly strength in the old term) of three kinds of agar and unit weight of bar style agar were investigated. All of the samples were produced in Nagano during 1961-1968.
The widest ranges of gel strength values in these 8 years were 110 to 670 for 7, 064 samples of about 110 bar styIe agar factories, the value less than 100 to 720 for 5, 425 samples of stringy agar factories of far less numbers, and the value less than 100 to 1, 250 for 606 samples of 8 powdered agar factories. The yearly average values of gel strength were 259-316 for bar style agar, and 300-379 for stringy agar. The yearly averages of unit weight of bar style agar were 7.0-7.8g with the standard deviations of ±0.9 to ±1.0g.

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Melting points of 1, 335 samples, bar style agar and stringy agar, which were manufactured at about 120 seasonal agar factories in Nagano during the winter season from December of 1968 to March of 1969 were measured, and their distribution was analyzed. The minimum, the maximum and the average value of the melting points were 74.5°C, 95.0°C and 85.1°C, respectively, and 63.6% of the whole samples had the melting points less than 85°C.
In the graph showing the relationship between gel strength (s) and melting point (tm), the 1, 335 samples could be divided, by the line of s=380 to 390, into two groups having the different regression lines of tm on s. The biggest difference of melting point at any definite gel strength value was about 10°C.

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The distributions of melting point and gelation temperature of 124 bar style agars and 124 stringy agars manufactured in Nagano during December of 1968-March of 1969 were analyzed with respect to the species of the raw material seaweeds, The average melting point and gelation temperature of 96 products processed from the raw materials which were dominant with the Argentina Gracilaria verrcosa were respectively 79.3°C and 38.7°C, while those of 152 products processed from the raw materials Which Were mostly composed of the Japanese Gelidium species were respectively 87.3°C and 35.5°C.
The two groups of agar were so different each other not only in the distribution patterns of melting point, gelation temperature and temperature difference of melting and gelation, but also in the regression lines of melting point on gel strength that the agar included in the Argentina Gracilaria was estimated to be a different type of agar from the traditional Japanese agar.
A series of agar were experimentally processed from the raw materials mixed with the Argentina Gracilaria and the alkali treated Gracilaria of the other origins. The relationship between gelling properties and the mixed ratio of these two kinds of seaweeds was investigated to bring the results justifying the former findings.

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