Changes of chemical properties and composition of total lipids in nameko mushroom, pholita nameko during storage were studied. Nameko mushrooms were stored at 20°C for 6 days, 5°C for 8 weeks and -25°C for 5 months, respectively. The results obtained were as follows :
(1) Total lipid content in nameko mushroom stored at 20°C showed a tendency to decrease during storage. Then acid value and peroxide value of total lipids in samples stored at 20°C and 5°C increased during storage and the above changes show the oxidation of total lipids. While those in samples stored at -25°C showed scarcely the above changes.
(2) With regard to the changes of lipid composition of total lipids during storage, the decrease of glycolipid and phospholipid fraction contents and the increase of neutral lipid fraction content in total lipids were observed at three kinds of stored temperature. Especially these changes were remarkable in the case of samples stored at 20°C.
(3) Concerning the changes of lipid composition of neutral lipid, glycolipid and phospholipid fractions, the decreases of triacylglycerol content in neutral lipid fraction, cerebroside content in glycolipid fraction and phosphatidylethanolamine and phosphatidylcholine contents in the phospholipid fraction were observed at three kinds of stored temperature, especially these changes were remarkable in the case of 20°C storage.
(4) On the changes of fatty acid composition of total lipids and the above three lipid fractions, the decrease of 18 : 2 acid content and the increase of total saturated fatty acid contents were observed in the cases of 20°C and 5°C storage. On the other hand, the changes of fatty acid composition of the above lipid fractions were hardly observed at -25°C storage.
(5) From the above results, the storage at -25°C was effective for 5 months against the rancidity of lipids in nameko mushroom and the storage at 5°C was effective for 3 weeks, but the storage at 20°C was not effective.

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There has been little available report concerning the chilled storage on plum fruits cv. 'Ooishiwase'. Our preliminary experiments purporting to establish optimum storage temperature showed occurrence of typical chilling injury on plum fruits. The present study was carried out to clear this phenomenon in reference to its physiological aspects.
(1) The fruits stored under 0°C were remained the market quality for 40 days, that is 2 times longer than the fruits stored at 7°C. On the other hand, the fruits stored at -1°C were obviously sound until duration of 25 days thereafter chilling injury developed gradually. It could be suggested that optimum storage temperature on plum fruits would be at 0-1°C, with concern about chilling injury at -1°C.
(2) The fruits during storage under 7°C synthesized a larger amount of ethylene, due to an increase in ACC content and to sufficient activity of EFE. On the contrary, the fruits under storage below 0°C produced hardly ethylene, due to a reduced ACC content, in spite of having sufficient EFE activity as the fruits stored under 7°C. EFE activity declined with increasing duration of chilled storage.
(3) A break point of Arrhenius plot of rate of potassium ion leakage from tissue slices of plum fruits was found at -0.9°C. The break corresponded nearly with the critical temperature for chilling injury of plum fruits. When plum fruits were stored at -1°C for 25 days or longer, chilling injury developed gradually. On the flesh of chilled fruits white spots appeared thereafter the flesh became browning. The appearance of browning was found after a marked increase of the rate of ion leakage from the fruit tissues, and the total contents of phenol compounds increased remarkably in the fruits stored under -1°C prior to the appearance of white spots.

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This paper discusses the changes of nitrite and nitrate in various animal meats (pork, chicken and rabbit), meat cuts (loin, shoulder and leg) and meat products during processing. Both of the nitrite content of 0.07-0.09ppm and the nitrate content of 1.57-5.54ppm in the raw meat were very small amount and the distribution of their contents in meat cuts showed not much difference.
Although curing showed an increase of nitrite and nitrate contents during the addition of spices, nitrite and nitrate contents were also found to increase during such processings as drying, smoking and steamcooking without the addition of color former.
The distribution of nitrite contents of ham products was then measured and nitrite contents of ham products were greater in the outer (0.62ppm) than the inner portion (0.28ppm) of the ham.
When concentration of nitrite salt in pickle was varied from 0 to 500ppm, an increase of nitrite residual content in meat products was also observed. Addition of nitrite at 50ppm concentration brought bright red color to meat products

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