White leaf protein concentrates (white LPC's) were precipitated by varying pH (2.0, 4.0 or 7.8) and temperature (4°C or 80°C) of the brown juice obtained as a supernatant at pH 5.0 expressed white clover (Trifolium repens) juice, and the precipitates were freeze-dried. Similar chemical compositions were found for all LPC's when the LPC's were washed with an acidic aqueous solu tion. However, the yield of white LPC and its functional properties were affected by the preparative procedures. The LPC prepared by acid precipitation without heating showed better functional properties than the other preparations. By this technique, however, at most 60% of the protein was recovered from the brown juice. Though the yield of white LPC was improved by heat coagulation followed by washing at pH 4.0, heat treatment produced more bulky, more water and oil absorbing, and less soluble white LPC than that obtained by acid precipitation. These observations suggest that heat treatment in preparing white LPC might promote the formation of intermolecular bonds which produce insoluble hard particles having larger void volume.

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In order to improve the texture of cucumber pickles, the effect of minerals (K, Ca, Mg, Al) on the firmness was studied by analyzing the characteristic properties of pectin components of cucumber pickles, and the results were obtained as follows: (1) On calcium chloride treatment, the firmness increased with the increasing amount of Ca added. Using calcium chloride with potassium chloride, as well as calcium chloride with magnesium chloride, little change was found in the firmness as compared with the use of calcium chloride alone at the same level as Ca content. Aluminum ion might restrain the texture firming effect of calcium chloride when used with calcium chloride. (2) The Ca content in alcohol insoluble substance (AIS) increased with the increase of Ca concentration used for the treatment. When potassium chloride or magnesium chloride was used with calcium chloride, almost the same Ca content in AIS was found as that treated with calcium chloride alone at the same Ca-level. The addition of aluminum chloride distinctly decreased it. (3) On the pectin composition of AIS, the water soluble pectin and the hydrochloric acid soluble pectin were always found to be in a smaller amount than other pectin fractions. Hexametaphosphate soluble pectin fraction (PSP) was found more abundantly in all treated samples, especially when used calcium chloride with aluminum chloride. The sodium hydroxide soluble pectin fraction was remakably decreased than PSP after aluminum chloride treatments, while it obviously remained higher in other treatments.

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The main purpose of this study was to see the effect of water on lipid oxidation of freeze-dried pork which received steam treatment after freeze-drying. The changes of peroxide value, oxygen absorption, moisture content, water activity, moisture sorption isotherm, monolayer moisture content, surface area and unfrozen water content were studied in the samples treated with various steaming time ranging from 15 minutes to 120 minutes. Measurements of peroxide value, oxygen absorption, monolayer moisture content and surface area were minimum at 60 minutes of steaming. On the other hand, moisture content, water activity and unfrozen water content increased as the time of steaming lengthened. Moisture sorption isotherms of the steamed samples showed the decrease of the amount of water in the entire water activity range studied compared with that of the sample not steamed. The sample steamed for 60 minutes showed the highest stability for lipid oxidation, and moisture content and monolayer moisture content of the sample were 4.20% and 2.75%, respectively.

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Bacillus coagulans is well known as a causative organism of flat-sour type spoilage of canned foods. The organism is generally considered to be an important target in heat processing not for low-acid foods (pH value is more than 4.6) but for acid foods (pH value is equal to or less than 4.6), because it can grow well in acidic foods and it had been isolated frequently from spoiled tomato products. Authors, however, isolated the organism from canned low-acid foods such as corn soup (pH 6.2), corned beef (pH 6.1), sukiyaki beef (pH 5.5) and formulated liquid meals for medical use (pH 6.3) representing flat-sour spoilage. One of the isolates grew well at 65°C. Three of four isolates examined produced spores having strong heat resistance. The D (decimal reduction time of survival spores) and z (the slope index of a thermal death time curve) values for the spores heated in 0.01M phosphate buffer solution (pH 7.0) were 1.4 to 1.6 minutes at 121°C and 7.2 to 7.8°C, respectively. The spores showed the similar strong heat resistance also in the food substrates. The D values for the spores heated and subcultured in food substrates were 11.2 minutes at 115°C in corn soup, 4.5 minutes at 110°C in corned beef, 6.5 minutes at 115°C in sukiyaki beef, and 11.3 minutes at 115°C in formulated liquid meals for medical use. Thus, it might be difficult to inactivate the organism, maintaining desirable food quality, solely by means of heat processing.

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(1) Stimulative effect on the acetic acid production of Acetobacter pasteurianus No. 2 was observed, when 1% of mirin or shiomirin was supplemented to basal medium. (2) Effective substances in mirin were separated into neutral and acidic fractions on the ion exchange column. Effective substances in the neutral fraction were composed of glycerol and glucose, and those in the acidic fraction were suggested to be organic acids such as lactic acid and succinic acid. (3) It was observed that the rate of acid production was considerably stimulated when mirin was supplemented to the medium of sake cake or non-salt soybean miso. (4) Furthermore, the vinegar obtained from the medium with mirin and non-salt soybean miso had more abundant amino acids and non-volatile organic acids in quantities than that of sake cake alone. From the above results, mirin or non-salt soybean miso was considered to be suitable for a new type vinegar production.

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The insoluble solid of peel (PIS) of Satsuma mandarin (Citrus unshiu Marc.) was prepared by the homogenization with 0.1M phosphate buffer according to KANNER'S method, A soluble ascorbate oxidase (AAO, EC 1. 10. 3. 3) was eluted from the PIS with the dissolving of pectin by the incubation in McILVAINE buffer (pH 6). In the residue of the PIS, an insoluble AAO activity was found by the difference spectral method described in the previous paper. The soluble and insoluble enzyme fractions were separated from the PIS by the above treatment. Both enzyme fractions obtained showed strong activity at pH 5.5 and 6.5 and at the temperature 35°C and 45°C, respectively. Their properties corresponded to those of the partially purified AAO of Satsuma mandarin fruit and the insoluble AAO in PIS of mature orange. These results suggest that AAO in citrus PIS may be loosely bound to or tightly adsorbed by the polysaccharide such as pectin. The activities of soluble and insoluble AAO in Satsuma mandarin peel were measured during the fruit ripening. Both enzymes had a high activity at early growing stage and the activity sharply dropped as the fruit developed. While, a weak activity of these enzymes was detected in the fruit during maturation from August to the mature stage.

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When acid protease preparation was added to packaged beer to prevent the papain-involved gushing, the white flake-like precipitates were formed after several days at room temperature. The precipitates were mainly consisted of β-glucan (β-(1→3):(1→4)=1:4.0) and pentosan (Arabinose: Xylose=1:2.7). In order to clarify the cause of the precipitation, its precursor and the factor which took part in these precipitate-formation were studied. The precursors of precipitates were β-glucan (β-(1→3):(1→4)=1:2.3) and arabinoxylan (Arabinose:Xylose=1:1.4-1.7) in beer, and these origins were considered to be β-glucan from barley endosperm cell wall and arabionoxylan from husk, respectively. The precipitate-forming factors which were isolated from the enzyme preparation, were found to be mainly β-glucanase and arabinofuranosidase.

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The change in tocopherol contents during manufacturing and storage of "natto" and "hikiwarinatto" was studied. Tocopherols were extracted with a mixture of chloroform: methanol (2:1) and were determined by high performance liquid chromatography with fluororesence detector. Tocopherol contents in soybeans were increased by both soaking and steaming, and the rate of increment was observed to be about 30 percent on dry base. It seemed that the increment was caused by the exudation of some part of water soluble materials of the soybeans to the steam waste water and soaking water. During storage, tocopherol contents showed little change. Exceptionally, in "hikiwarinatto" stored for 7 days at 25°C, 95 percent of α-tocopherol was decomposed accompanied with deterioration. Twelve samples of commercial "natto" and "hikiwari-natto" were examined, and tocopherol contents on average were as follows, α-tocopherol:1.3, β:0.2, γ:9.2, δ:3.7, and in total:14.3mg/100g wet basis.

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Quality of Satsuma mandarin single strengh juice from which hesperidin was removed with adsorbent was studied. (1) When juice containing hesperidin of 75mg/100ml was bottled in one liter glass bottle, hesperidin in juice began to change into insoluble form rapidly just after preparation. Soluble hesperidin of suspension parts in juice containing 75mg, 50mg and 25mg/100ml reached equilibrium at the level of 10mg/100ml. (2) Pulp of suspension parts in bottled juice precipitated by forming aggregate with hesperidin, and pulp content reached equilibrium at the level of 0.2%. In hesperidin removed juice, Pulp content was kept about 1% for 20 days after storage. (3) Flock was formed on the inner surface of bottle in the juice containing hesperidin of 25mg and 50mg/100ml. But in juice containing hesperidin of 75mg/100ml, hesperidin precipitated with pulp particles. Flock was not formed in hesperidin removed juice at all. (4) Pulp sizes of suspension parts in control and in hesperidin removed juice distributed less than 2μ and wide range of 1-10μ, respectively. (5) Hesperidin removed juice retained 5 times of pulp, about 2.5 times of carotenoid and also 4 times of turbidity in suspension parts, compared with those of control juice, after storage for 20 days at 20°C. Recoverable oil content of hesperidin removed juice was kept about 65% of initial amounts after storage for 20 days.

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The aroma of the powdered new seasoning (Amistar) made from the hydrolyzate of whole krill was investigated and compared with the original liquid hydrolyzate. Amistar contained less amounts of chlorinated products and more various kinds of characteristic components than the original liquid type seasoning, and especially the secondary products formed by amino carbonyl and Aldol type condensation reactions were seemed to give good effects on the aroma of Amistar.

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On 9 kinds of biscuits and cookies, 13 of crackers and snak cakes, 4 of pies and cakes, 5 of chocolates and 3 of rice cakes, tocopherol (toc) contents and polyunsaturated fatty acid (PUFA) compositions were analyzed. (1) The mean of α-toc and PUFA contents in biscuits and cookies analyzed in this study were 2.09 (0.92-6.79) mg% and 2.41 (1.41-4.59) g%, respectively, and a ratio of a-toc and PUFA was 0.85. The mean of α-toc and PUFA in crackers and snak cakes were 4.27 (0.30-15.55) mg% and 8.06 (0.92-6.79) g% and a ratio was 0.60. The mean of α-toc and PUFA in pies and cakes were 2.61 (2.11-2.90) mg% and 4.83 (2.71-7.81) g% and a ratio was 0.63. The mean of α-toc and PUFA in chocolates were 0.43 (0.33-0.55) mg%, the lowest of all confectioneries analyzed, and 2.34 (1.68-4.22) g%, respectively, and a ratio was 0.21, this being considerably lower than that recommended for adequate vitamin E nutrition by HARRIS. The mean of α-toc and PUFA in rice cakes were 4.83 (0.33-10.0) mg% and 5.80 (0.81-8.47) g% and a ratio was 0.71. These results indicate a possible contribution of confectioneries, especially α-toc enriched or wheat germ added goods, as a source of dietary tocopherols. (2) POV of each sample was less than the restricted value.

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