The conjugated lipids in the pulp of apples cv. Ralls Janet which are resistant to cold temperature and apples cv. Starking Delicious which are sensitive to cold temparature were studied with reference to mechanism of chilling injury. The following conjugated lipid components were identified; phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidic acid, phosphatidylserine, cardiolipin, monogalactosyldiglyceride and digalactosyldiglyceride. The contents of total phospholipids and that of the respective components in Ralls Janet were larger than those in Starking Delicious. After the storage at 0°C, the contents of total phospholipid and that of the respective components decreased. The degree of decrease in Starking Delicious was larger than those in Ralls Janet. On the other hand, the contents of total sterol, free sterol, combined sterol in Ralls Janet were larger than those in Starking Delicious. Furthermore, the contents of monogalactosyldiglyceride and digalactosyldiglyceride in Ralls Janet were also larger than those in Starking Delicious. From the above results it was concluded that, higher ratio of PC/PE in Ralls Janet than that in Starking Delicious may cause the resistance to chilling injury in Ralls Janet playing a role in lowering phase transition temperature. Though many kinds of polar groups of other conjugated lipid components must be considered. The radio of unsaturated fatty acids to total fatty acids of Ralls Janet was higher than in Starking Delicious as described in a previous paper.

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The effect of alcohol-modification on emulsion stability (ES) of soy proteins was investigated using the following four alcohols: methanol, ethanol, iso-propanol and n-propanol. The ES in the pH range below 7, especially at the isoelectric point, was effectively increased by the modification. The effect of modification was remarkably affected by the pH during the treatment. The ES of the 7S protein rich fraction (7S PRF) and 11S protein rich fraction (11S PRF) correlated with that of their soluble' protein fractions respectively, with the same correlation being observed between the ES of the ethanol-modified 7S PRF and 11S PRF and that of their insoluble protein fraction. The acid-precipitated protein (APP) modified with n-propanol was adsorbed to the interface between water phase and oil phase around three times as much as the unmodified APP. Taking the above facts and the nature of the effect of alcohols on soy proteins into cosideration, it was presumed that improvement of the ES resulted from the alcohol-modification closely correlated with lipophilization of the soy protein molecules.

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This experiment was carried out to elucidate the effect of frozen storage time on the properties of egg yolk including viscosity, solubility, emulsifying capacity (EC) and emulsion stabilizing capacity (ESC). Plain yolk and salted yolk with 10% NaCl were frozen and stored at -20°C being sealed tightly in the period of 3 to 180 days. Under these conditions, the increase of free fatty acid was practically not detected. However, their thiobarbituric acid value increased gradually during frozen storage. Apparent viscosity of plain yolk was markedly increased and its solubility was decreased by storage for 3 days. During subsequent storage, apparent viscosity increased gradually. Reduction of EC and ESC of plain yolk virtually corresponded to the viscosity change. Although the apparent viscosity of frozen-thawed salted yolk increased gradually in proportion to storage time, lowering of its solubility was not detected. As in the case of plain yolk, EC and ESC of salted yolk were reduced during frozen storage. However, their reduction rate was smaller than in plain yolk.

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The purpose of this paper is to obtain basic data to calculate the amount of ice required for ark ice bunker in a hydrocooler. The melting phenomenon of an ice sphere held in flowing water was investigated experimentially. Summary of the results is as follows: 1) An ice sphere melted in an almost spherical shape on the front hemisphere, while it changed to an anomalous shape on the rear hemisphere. There was a stagnant point on each hemisphere. 2) Separation point moved forward with increase in Reynolds number. 3) Local Nusselt number was large near the both stagnant points and small at the separation point. The dependence of local Nusselt number on Reynolds number was minmum near the front stagnant point and maximum near the rear stagnant point. 4) The smaller Reynolds number became, the larger the ratio of heat transfer rate over the front hemisphere to that over the whole sphere became, while the larger Reynolds number became, the larger that ratio of the rear hemisphere became. 5) Average Nusselt number was given by the following equation. Nu=2+0.3Re^0.59 Pr^1/3 Average Nusselt number was smaller than that in the heat transfer without fusion, presumably due to the resistance of melted water film to heat transfer.

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Determination of selenium in milk powder was carried out by atomic absorption spectrophotometry attached with a selenium hydride generation apparatus. About one g of sample was wet-ashed at 100-150°C on a hot plate in the presence of perchloric acid and nitric acid. To the digested solution stannous chloride and zinc slurry were added, and selenium hydride was generated, and the gas was conducted to the atomic absorption spectrophotometer. The absorbance was proportional to selenium hydride over a wide range of its content. This method was successfully applied to the determination of the selenium content of commercial milk powders by the values obtained which were within 0.04-0.12 ppm.

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Ascorbic acid(ASA)in tomato products was determined by high performance liquid chromatography (HPLC) with a UV detector(254 nm)by stainless column(4.6×250 mm)packed with Fine SIL C₁₈-10. The mobile phase was 1% phosphoric acid. Tomato juice or vegetable juice was diluted with 4% metaphosphoric acid and passed through a micro filter (0.45μ). There μl of the filtrate was injected into a liquid chromatograph. The retention time of AsA was 4 minutes and 20 seconds. Analytical time of one sample was less than 14 minutes. The average recovery of AsA was 98.6%. AsA in tomato products was determined by HPLC and the indophenol method(AOAC method). With the average of the 8 different lots of tomato juice, the analytical value by indophenol method was 7.8% more than that by HPLC. It was caused by reductones except AsA. AsA in tomato juice that was oxidized by heating or oxygen was also determined by two methods. As a result, it was concluded that HPLC was very useful to grasp accurately and rapidly a decrease of AsA during processing or storage of tomato products.

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A conductometric method has been studied for the determination of caffeine in food. Anonaqueous conductometric technique was introduced for this purpose. The mixed non-aqueous solvent system containing 1-5 mg of caffeine was composed of 10 ml of chloroform, 5 ml of acetic anhydride, and 3 ml of 0.01 N perchloric acid/glacial acetic acid. The conductance measured with the mixed solvent system gave well correlation with the caffeine content. The following equation was set up between the measured conductance (y) and the content of caffeine (x). y=-11.1x+b (cell constant= 0.096 cm^-1) Where, y and x were represented in μmho and mg, respectively. The intersection of the y-axis, (b), was determined as follows. Caffeine was extracted from the standard solution containing 30 mg of caffeine. The caffeine extract (chloroform phase) was mixed with acetic anhydride and 0.01 N perchloric acid/glacial acetic acid in the ratio described above. Then, the conductance was measured with the mixed solvent system. The intersection of y-axis, (b), was determined by using the measured conductance value in the equation y=-11.1x+b. This conductometric method was applied to the determination of caffeine in tea leaves and compared with the Kjeldahl and gas chromatographic method. This method can compete in terms of accuracy and precision with Kjeldahl and gas chromatographic method and is more convenient and rapid than the others.

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The Ca content in tea was compared by using the both methods of an inductively coupled plasma-atomic emission spectrometry and an atomic absorption spectromety. The Ca content in tea could be determined directly by the inductively coupled plasmaatomic emission spectrometry. The interference by P and other major elements on the assay of Ca was not recognized. However, on the atomic absorption spectrometry, the addition of high concentration(over 1, 000ppm) of Sr in the assay solution was indispensable to eliminate the the interference of P.

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Textural changes of cooked rice on staling were investigated by the two point mensuration method and biting test in kernel level using a Tensipresser.
The two point mensuration method already reported was useful to compare the texture of cooked rice on staling. Differences in the textural changes between glutinous and non-glutinous cooked rice kernel on staling were also showed by this method. Changes in the mouth feel of cooked rice on staling were given by the parameter of adhesiveness/hardness or adhesiveness/slope 1.
Biting test of cooked rice kernel was also useful to compare the textural changes on staling. Changes in the fracturability of cooked rice kernel on staling by biting test also clearly reflected the changes of the mouth feel. Fracturability/hardness of cooked rice kernel affected by the rice variety, storage period, added water and or holding time and temperature after cooking was also correlated to the palatability of cooked rice.

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This work was undertaken to determine suitable amount of NaNO₂ and sodium ascorbate (NaAs) applied to the manufacturing process of hams by a multiple pickle injector, based on the data conducted by previous study; the injection of 15% of pickle solution and 2.2% NaCl in weight ratio to fresh pork loin produced satisfactory results. 1) The amount of NaNO₂ added was significantly related to the residual amount of NO^-₂ in the cooked cured loins. In case of short curing for 1 or 2 days, 100 ppm of NaNO₂ gave a relevant amount of residual NO₂^- (less than 70 ppm)as provided by Japanese Food Hygien Law. 2) The amount of NaNO₂ added was significantly related to the color forming ratio, which rised with increasing amount of NaNO₂. 3) In the presence of fixed amount of NaNO₂(100 ppm), an addition of NaAs more than 300 ppm brought about the pronounced effects on the decrease of residual amount of NO^-₂ as well as on the increase of color forming ratio. 4) When the cooked cured loins containing NaNO₂ (100 ppm)alone were exposed under natural light for 30 minutes, their a-values in Hunter evaluation were lowered to some extent. In case of the cooked cured loins containig NaAs in addition to NaNO₂, their a-values were slightly lowered and the b-values were considerably rised with increasing amount of NaAs.

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