For the preparation of soaked rice of high level moisture and capable to be weighed and packed easily in a container, the soaking of superheated-steam-treated rice was investigated. Raw rice of 14% moist. content was soaked firstly for 2hr at 20°C, and thus soaked rice (moist. content 34%) was trated for 2.5 min at 150°C in a flow of superheated-steam. The steamed rice (moist. content 32%) was soaked secondly at 20-100°C. The 2nd-soaked rice products of 55-60% of moisture content was possible to be weighed and packed easily in a container. The 2nd-so aking-rate equation was expressed as a first-order rate equation.
dw/dθ=0.01492(we-w)
we=1.294×10-5tt²+7.870×10-5t+4.562×10^-2
where, w, we: soaking intermediate, equilibrium weight (g), θ: soaking time (min), t: soaking temperature (°C)

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During the process of roasting coffee, many nonphenolic acids, formic, acetic, lactic, etc., were produced and it was presumed that the precursor of these acids was carbohydrate, mainly sucrose. In order to prove it, sucrose and the mixture with chlorogenic acid were roasted at 190°C for twenty to twenty-three min and produced acids were determined by gas chromatography. Formic, acetic, lactic, glycolic, levulinic, oxalic, malonic and succinic acids were produced from sucrose. The same acids were detected from the mixture of sucrose with chlorogenic acid. The quantitative changes of these acids in the course of roast were clarified. Monosaccharides produced the same acids by the roast. From coffee polysaccharides such as arabinogalactan and cellulose, citric acid was produced in addition to formic, acetic, oxalic, malonic and succinic acids.

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Six different sizes asparagus were packed in tin containers with brine and processed at 115.2, 117.6, 118.8, and 119.9°C for 30min., and at 115.2°C for 20, 30, 40, and 50min., respectively. After opening the cans, deflection angle and colour intensity of the contents were measured. The results obtained are summarized as follows:
(1) The deflection angle increased in according to the processing time from 20 to 50mins. at 115.2°C, but the increase became slightly by raising up the temperature from 115.2°C to 119.9°C.
(2) The deflection angle caused in large size asparagus was smaler than that in small size asparagus when both were processed at same temperature and time.
(3) Little difference was measured in colour intensities with large and samll size asparagus. Browning discolouration of the contents developed markedly by processing more than 40min. at 115.2°C, but significant browning developing was not found through raising the processing temperature from 115.2°C to 118.8°C.
(4) Asparagus should be processed at 115.2°-118.8°C for 30min. or at 115.2°Cfor 30-40min. after blanching for 30sec. with Giant to Colossal sizes (diameter of the stalk is 21-35mm); processed at 115.2°C for 30min. after blanching for 15sec. with Mammoth to Large sizes (diameter of the stalk is 12-20mm); and processed at 115.2°C for 20-30min. after blanching for 15sec. with medium to Small sizes (diameter of the stalk is 6-11mm).

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The effects of various food additives and natural polymers on liquefying point, gel strength, modulus of elasticity and brittleness of agar gel (1.0%) were investigated. It was found that the liquefying point of agar of which concentration was from 0.01 to 1.0% increased in accordance with the increase of contents of several salts (e.q. ammonium and sodium sulfate) and some polysaccharides (e.q. locust bean gum and guar gum). The addition of sodium sulfate, monosodium L-aspartate and magnesium chloride etc. resulted in the rise of gel strength. It may be presumed that the additives increased the agar solubility. By addition of the substances which increase gel strength of agar, the reduction of modulus of elasticity and brittleness of agar gel were usually found.

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In connection with the oil-solubilization phenomenon observed in the aqueous solution of soy sauce extract, the effects of some carbohydrates in soy sauce extract on micelle formation were investigated by an electric conductivity method. The aqueous solution of soy sauce extract gave the maximum conductivity at the concentration of about 35% (w/v), which elucidated the micelle formation of the solutes around the point. On the other hand, the solution of glucose, galactose and some dextrins as well as saccharose or maltose also gave the maximum values in electric conductivity at about 30% (w/v). The conductivity of the carbohydrate solutions at the micelle forming concentrations apparently decreased and micelle formation was promoted when polypeptone as a model nitrogenous ingredient was present in specific concentrations. These results suggest that the micelle formation of the carbohydrates is accelerated by the surface-active nitrogenous ingredients in soy sauce extract and the solubilization of fats or oils occurs by penetration or absorption of these substances into or on the micelle.

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Nitrate and nitrite contents and the activity of nitrate reductase of Japanese radish were analyzed during growing, storage and pickling with salt or salt-bran.
(1) The varieties of radish used in this experiments were Minowase-spring type (sowing, April; harvesting, end of June), Minowase No 2-summer type (sowing, August; harvesting, end of October), and Miyasige (sowing, September; harvesting, end of November).
2) Nitrate concentration in a root was higher toward the root tip and there were no significant difference in nitrate contents among cortex, vascular bundle and parenchyma at the middle part of the root.
3) Nitrate concentrations of the petioles, roots, and leaf blade were 1400-1600ppm, 700ppm, and 200-350ppm 40 days after sowing, respectively. During the growing stage from the above period to the harvesting date, nitrate contents of these parts decreased by about one-tenth of the initial ones. In Miyasige variety for which the times of fertilizing was increased, the decreasing rate for the period was about a half.
4) Nitrate reductase activity in Minowase-spring type was higher in leaf blade and lower according to the decreasing order of petioles and roots. During the growing stage, the activity increased in leaf blade, but were constant other two parts.
5) These three varieties of the radish roots were stored at 1 and 20°C. Changes of nitrate contents during the storage were not noted in both Minowase varieties, but in Miyasige, .itrate contents decreased slightly. Nitrate reductase activity were maintained at the low level during storage.
6) Changes of the amount of nitrate were observed through the process of pickling with saltbran. After 26 days, the amounts became to be the equal level of nitrate in the roots and saltbran. Maximum content of nitrite was only 0.4ppm in the process.
7) In the process of pickling with salt only, the changes of nitrate contents in the roots and in brine both at 6 and 20°C were similar to those of pickling with salt-bran. Nitrite contents had maximum, 3 days after the start of pickling at 20°C (30ppm in the root and 230ppm in the brine), but the formation of nitrite at 6°C was suppressed markedly.

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Changes of trypsin inhibition activities in Yuba-film and the remaining soymilk prepared by laboratory-scale process were investigated.
Chromatography with Sephadex G-75 and DEAE-cellulose were caried out to com pare the trypsin inhibitor (abbre. TI) patterns between Yuba-film and the remaining soymilk.
1) The contents of TI in Yuba-film was 4.7-5.02×103μg per one gram and 17-23×103μg per one film. TI was found to be 24.32% in all Yuba-films and 38.94% in the last remaining soymilk, indicating that 36.74% of TI was inactivated during Yuba processing. Furthermore 60.22% of this inactivation was occured by the time the 4th Yuba-film was obtained, then the rest of TI was gradually inactivated. Specific activity of TI in Yuba-film was 7.14-7.40 independent of the order of Yuba processing steps. Specific activity of TI in the remaining soymilk were decreased from 12.41 to 8.51 along with Yuba processing steps.
2) TI existed in the soymilk, the Yuba-film and the remaining soymilk were fractionated into two peaks (A and B peak) by chromatography with Sephadex G-75. A peak of Yuba-film was eluted earier than that of the soymilk. Amount of A peak of the 12th Yuba-film was more decreased than that of the 4th Yuba-film.
3) TI fractions obtained from chromatography with Sephadex G-75 were further fractionated by chromatography with DEAE-cellulose. Both TI in the Yuba-film and the remaining soymilk were fractionated into seven peaks (F₁-F₇) respectively, whereas, that in the soymilk were fractionated into 6 peaks and one trace peak. As compared with TI patterns of the Yuba-film and the remaining soymilk, F₇ in Yuba-film was a trace but that in the remaining soymilk was 11.6-22.5%. of the total TI. As compared with TI patterns of the 4th and 12th Yuba-films, F2 in the 4th was 31.4%, whereas, the 12th was a trace. It seems that these differences of TI patterns were derived from inactivation caused by heating during Yuba processing.

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The characteristics of oxidative deterioration of roasted peanuts prepared by deep fat frying (oil roasted peanuts) and by heating in an oven (dry roasted peanuts) were investigated to obtain the following results.
1) Roasted peanuts were oxidized very rapidly in spite of a higher stability of the oil extracted from raw peanuts. Corelation of the oxidative deterioration of the roasted peanuts to fat stability of the raw peanuts was not recognized.
2) Peanuts roasted insufficiently or excessively, which could not be used for food, had a higher stability to oxidation, but peanuts roasted properly and good for food were oxidized more rapidly during storage.
3) The degree of oxygen supply is an important factor for the oxidative deterioration of roasted peanuts, that is, keeping the roasted peanuts in a sealed container with lower oxygen permeability can inhibit more effectively the increase of peroxide value than keeping in an open state to air.
4) When raw peanuts kept under proper conditions, stability to oxidation did not decrease for a long time.
5) The surface oil, which was extracted from granular samples, of dry roasted peanuts was more rapidly oxidized than that of oil roasted ones, whereas the degree of oxidation in the whole oil, which was extracted from crushed samples, was almost the same in the both case. After being by deep frying, peanuts were coated with coconut oil containing 0.1% natural tocopherol mixture as an antioxidant. This is very effective for inhibiting the oxidation of the surface oil, however, the internal oil of the peanuts was oxidized very rapidly regardless of coating with tocopherol.
6) Nitrogen gas exchange packaging is extremly effective for keeping roasted peanuts good in quality and the initial oxygen concentration in the bag at packaging did not require below 2%.
7) It was suggested that lipoxigenase activity in the peanuts was concerned with the oxidative deterioration of roasted peanuts, that is, the treatment of raw peanuts with aq. solution of hydrogen peroxide (1%) could inhibit effectively the oxidation of the peanuts after roasting.

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