When glutinous rice (R) colored with the aqueous yellow extract (YE) of the Gardenia fruit (GF) was steamed, the color sometimes changed from yellow to green unexpectedly. The experiment was done to clarify the phenomenon of the greening.
The greening occurred when R was steeped in YE at 30-40°C for 24 hours and then steamed, and no greening occurred at 20°C or below for 24 hours or at 30°C for 12 hours. The greening was weaker when the well-washed R was steamed, and stronger when R with addition of rice bran (RB) was steamed.
Furthermore, an experiment of greening YE was carried out by using RB or its extract. The result showed that the greening did not occur when RB was heated previously. The greening was inhibited when silver ion was added. The green liquid obtained by this experiment had a maximal absorbance at 440and 590 nm in the visible range. We may conclude on the basis of this experiment that a green color consits of two kinds of color, namely, yellow and blue.
The phenomenon of greening seems to indicate that iridoid glycoside (such as geniposide) contained in GF was liberated into iridoid compound (such as genipin) by the function of enzyme contained in R or RB. The phenomenon also revealed that iridoid compound turns into blue color when it was heated with amino acids.

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A research was made to investigate how the addition of bread affected microflora and taste in the early stage of “Nukadoko” (mixture of rice bran and salt for making vegetable pickling) aging. Changes in lactic acid bacteria, yeasts and constituents of the “Nukadoko” with or without bread in the early stage of aging were followed for a period of 5 weeks. Preference for pickling cucumbers in both cases was determined by sensory evaluation. The results are summarized as follows.
It was not recognized that there was a difference between “Nukadoko” with and without bread in the early stage of aging. In “Nukadoko” with bread, acidity (as quantity of lactic acid) was 0.9-2.2% and the pH was 5.2-4.2 for a period of 5 weeks. The lactic acid bacteria started from 10⁴ colonies/g, showed the maximum count of 10⁸ colonies/g at the 2 nd and 3 rd week and reached 10⁷ colonies/g at the 4 th week. The yeasts showed 10⁷ colonies/g between 1 and 2 weeks and reached a stable level of 10⁶ colonies/g between 3 and 5 weeks. Although coccus was the only lactic acid bacteria until the 2nd week, bacillus appeared as aging proceeded and was dominant at the 5 th week. These results were almost the same as “Nukadoko” without bread.
The sensory evaluation of flavor, sourness, color and total acceptance on the pickling cucumbers in both “Nukadoko”s were determined. Any significant difference was not obtained in both pickles.

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An apparatus which is reproducible on repeated run has been designed and constructed for the experiments of pan-frying. A stainless steel frying pan was placed on an aluminum plate, the temperature of which had been kept constant. And the pan was heated on the whole surface of the aluminum plate and maintained at a fixed temperature. A definite quantity of each sample oil was applied onto the heated pan and quickly spread over its whole surface. After a definite time of oil heating, the pan was cooled rapidly by placing it on wet cloth.
The deterioration of edible oils and fats was investigated with regard to the changes in acid, peroxide and total carbonyl values under the simulated pan-frying conditions, and following results were obtained.
1) When soybean oil was thermal-oxidized to the extent of total carbonyl value of 50 meq/kg at the specific surface area of 82.5 cm²/g, a heating temperature-heating time relationship was as follows: at 160°C for more than 10 min, at 180°C for 6 min, at 200°C for 2.7 min, at 220°C for 1.1 min, at 240°Cfor 0.5 min and at 260°C for 0.25 min.
2) The rate of oxidation in soybean oil varied in proportion to the specific surface area. The more the heating conditions were strict, the more the specific surface area affected the rate of oxidation.
3) Out of oils tested, rice and corn oils were comparatively thermostable, but fats like lard and tallow were very easy to deteriorate at elevated temperatures.

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Deterioration of the sardine lipids and decrease of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) during various cooking procedures were examined. Oxidative deterioration was evaluated by the measurement of POV, CV, AV, and the EPA and DHA contents in the lipids were determined by gas chromatography.
The results obtained were as follows: (1) In boiled or grilled sardine lipids, POV and AV showed almost no change, but CV increased twice. (2) POV and CV in fried sardine increased, and however, its AV did not. (3) While POV, CV and AV in pickled sardine stored for 1 hr and 2 days increased 4times, the increase of POV and CV stored in vineger added with lemon juice for 2 days was suppressed. (4) POV in bottled sardine showed a great increase during 2 months, and then decreased. CV sdowed almost no change. (5) The differences in EPA and DHA contents were observed among the various ways of cooking.

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Nasu-no-tsuchizuke is a traditional food of eggplants in Fukushima area. It is made by salting eggplants in soil paste which is made of the soil used for many years.
Nasu-no-tsuchizuke and other three kinds of salted eggplants with 5% salt were prepared to be evaluated on sensory qualities (appearance, flavor, texture and overall evaluation). Samples were nasu-no-tsuchizuke, salted eggplants in the soil paste made of paddy field, salted eggplants in deionized water with 0.5%potassium alum. and salted eggplants in deionized water.
The qualities of four kinds of salted eggplants were evaluated as follows:
1) Nasu-no-tsuchizuke was preferred in the items of appearance, texture and overall evaluation, but not preferred in flavor.
2) Salted eggplants in deionized water with 0.5% potassium alum. were preferred in appearance.
3) Salted eggplants in the soil paste made by the soil of paddy field were not preferred in the items of flavor, texture and overall evaluation.
From the results mentioned above, it was concluded that the quality of the nasu-no-tsuchizuke was more excellent than that in other three methods.

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