Lipid composition and fatty acid composition of total lipids and neutral lipids extracted from seeds (kernels and seed coats) of "Yuzu" (Citrus junos SIEB. ex TANAKA), "Yuko" (Citrus yuko HORT. ex TANAKA) and "Sudachi" (Citrus sudachi HORT. ex SHIRAI) were investigated by means of silicic acid column chromatography, thin-layer chromatography and gas-liquid chromatography. The following results were obtained: (1) In the case of the above three kinds, the total lipid contents (%) were 22-24% (46-58% in dry matter) in kernels and 1-2% (2-6% in dry matter) in seed coats. (2) In three kinds, neutral lipid contents (%) in total lipids were more than 95% in kernels and more than 70% in seed coats. (3) The main lipid in neutral lipid fraction was triacylglycerol (TG, 91.5-93.1%) followed by 1, 2-diacylglycerol (1, 2-DG, 1.6-3.6%), 1, 3-diacylglycerol (1, 3-DG, 0.8-1.7%), sterol (St, 0.6-0.9%), monoacylglycerol (MG, 0.6-0.7%), free fatty acid (FFA, 0.4 -0.5%), sterol ester (SE, 0.4-0.5%) and hydrocarbon (HC, 0.2-0.3%) in kernels, and was TG (66.7-73.8%) followed by St (6.1-9.6%), MG (4.9-6.1%), 1, 2-DG (4.7-5.4%), FFA (3.0-3.4%), 1, 3-DG (2.5-2.9%), SE (1.9-24%) and HC (1.0-1.2%) in seed coats. (4) Fatty acid compositions of total lipids, neutral lipids and each component lipid (TG, 1, 2-DG, 1, 3-DG, MG, FFA and SE) of neutral lipid fraction in kernels and seed coats of three kinds were not remarkably different. The main fatty acids were C18:2, C18:2, C16:0 and C18:1 acids.

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Ion-exchange reactions between cations, K, Ca and Mg, bound to pectin and Na of NaCl added to pectin solutions were investigated in detail. Pectic substance, extracted from radish root by treating with hot 2% Sodium hexametaphosphate solution in pH 3.7, was acidified with HCl and dialyzed to prepare pectinic acid containing minor cations. Then, pectinic acid was converted to pectinates containing K, Ca and Mg independently or some of these cations by treating with the individual salts or the mixture of the salts, following dialysis to eliminate the excess salts. The formation of the salt of COOH residues in pectin with such cations was recognized by the IR spectral absorption method before and after the treatment. The cation content in the pectinates was determined by atomic absorption spectrometry. And the changes of cation content in the pectinates after treating with NaCl solutions in different concentration, followed by dialysis, were measured. The experimental results indicated that the initial cation content in the pectinate decreased in inverse proportion to the increase of Na content in it according to the increment of NaCl added, showing greater effect of Na to exchaging the cations in order of K>Mg>Ca in the pectinate.

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Extrusion cooking of the hatomugi (adlay; soft shelled job's tears) with a single-screw extruder was carried out, followed by the comparison of the qualities between the materials and the products. The results were as follows; (1) The extruded milled adlay showed good expansion, but were slightly inferior to those from the milled glutinous rice at the point of hardness and brightness. (2) Chemical components, color and amino acid composition changed only a little on extrusion cooking. (3) On extrusion, starch was gelatinized and solubilized to the water and the amylogram characteristics changed markedly. (4) It became possible to prepare the fine flours with the use of extrudate. (5) Extruded adlay revealed the increase of P.O.V. under the condition of 40°C and low humidity, but P.O.V. did not increase even after 8-week-storage at 40°C and 64% RH and 83% RH. (6) Increase of the fat acidity during the storage was remarkably repressed by the extrusion cooking.

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The general composition, components of sugar and inoganic cations were examined on vinegars made in China. The data obtained were compared to those of Japanese vinegars. (1) The amount of constituents of Chinese vinegars was higher than those of Japanese vinegars. The difference of components between Chinese and Japanese vinegars seemed to be caused by that of raw materials and the manufacturing method. The color of Chinese vinegars was dark like that of Japanese soy-souce and sediments were found in some vinegars. (2) The amount of glucose was the most dominant in Chinese vinegars followed by fructose. (3) The major inorganic cations of Chinese vinegars were K, Ca, and Fe, which decreased in that order. These cations will come from raw materials, water and pieces of apparatus for production.

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Kamaboko containing starch was stored at 2°C, and the factors affecting changes in expressible water and jelly strength of the kamaboko during storage were examined. Increase in expressible water and jelly strength of the kamaboko containing starch from tubers and roots such as potato and sweet potato starch during storage were larger than those of the kamaboko containing starch from seeds such as corn and wheat starch. But not such a tendency was found in the kamaboko containing amylomaized starch and tapioca starch. Expressible water and jelly strength of the kamaboko which had 74.5% moisture content during storage increased significantly with increasing the potato starch content in the range of 0-14.3%. Jelly strength of the kamaboko containing 12.7% potato starch during storage increased with increasing the moisture content in the range of 66.81-78.99%. When pH of the kamaboko containing 15% potato starch was adjusted at pH 6.0-9.3 by HCl or NaOH, minimum changes in expressible water and jelly strength were observed for the kamaboko adjusted to about pH 7. When the kamaboko containing 15% potato starch was cooked at 70-95°C for 30-110min, changes in expressible water and jelly strength of the kamaboko during storage were effected by the cooking conditions.

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Nutritional compositions of the leaves and stalks of Fuki (Petasites japonicus Miq.), Tsuwabuki (Ligularia tussilaginea Makino), Gobo (Arctium lappa L.) and Gishigishi (Rumex japonicus Houttuyn) were analyzed. The following results were obtained. (1) The nutritional compositions were superior in the leaves than in the stalks. (2) The decreasing rates of nutritional compositions by boiling-treatment were less in leaves than in stalks. (3) The nutritional compositions of Gishigishi which is not edible in Japan were superior to others.

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By using pickle starter containing only Lacto bacillus plantarum as lactic acid bacteria source, leaves of daikon (a sort of radish) (Raphanus sativus) was pickled under Sunki pickling method, namely the leaves were dipped in hot water, then they were piled up alternatively in an enameled vessel with pickle starter. The properties of the pickles (sample B) concerning crude protein, free amino acids, total amino acids and sensory test were studied, and were compared with those of Sunki pickles (sample C) simultaneously pickled by using the dried Sunki. The following results were obtained. (1) The crude protein contents increased by pickling treament. The degree of increase was larger in sample B (from 28.44 to 34.00%) than in sample C (from 28.44 to 31.24%). (2) The total free amino acid content of sample B (2490mg/100g) was about twice that of raw material (1218mg/100g), and that of sample C (418/mg/100g) was very small. Sample B was superior to sample C on sensory test. (3) Proper amounts of essential amino acids were contained in the leaves of daikon and they were retained through pickling treatment.

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Glucoamylase (α-1, 4 Glucan glucohydrolase, Exo1, 4, α-glucosidase E.C. 3.2.1.3.) from Rhizopus niveus was immobilized to cyanogen bromide-activated dextran. The glucoamylase-dextran conjugate was purified by gel filtration chromatography. It was found that 92% of the original protein of the enzyme was recovered in the conjugate and about 82% of the specific activity of the native enzyme retained. Some properties of the enzyme conjugate were investigated and compared with those of the free enzyme. The pH activity and pH stability of the immobilized enzyme were not much altered with the optimum pH at 5.5 as that of the free enzyme. Immobilized enzyme exhibited a wide range of temperature stability of 50-60°C as compared to the free enzyme. Heat inactivation at 55°C had less effect on the residual activity of the immobilized enzyme in which 60% activity was retained after prolonged heating for 60 minutes.

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A rapid method for determining the oil content of rapeseeds was studied by measuring dielectric constant. Stainlite Model 300 Los Oil Tester was used as an apparatus for dielectric constant measurement. Fifty two rapeseed samples were obtained from 9 prefectures, namely, Aomori, Fukushima, Ibaraki, Mie, Shiga, Fukuoka, Miyazaki and Kagoshima. There was a linear relationship (r=0.942) between oil contents determined by the ether extraction method and oil tester values by the dielectric method. This method was more superior than the ether extraction method in simplicity and rapidness. However, o-dichlorobenzene used as a solvent in the measurement has a problem in safety.

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It was demonstrated that an effective way of softening the texture of Imo-karinto, deep-fat fried and sugar-coated sweet potato product, was to pre-treat strips of sweet potatoes by blanching followed by freezing. The period of blanching in boiling water depended on the size of sweet potato strips. Adequate period of blanching strip whose size was 3×3mm, 5×5mm, 7×7mm and 10×10mm thick (length, about 5cm) each was in the range of 25-30, 30-40, 40-60 and 60-90sec, respectively. The hardness and oil content of Imo-karinto were not affected by the temperature and the period of freezing. The deep-fat fried products with a certain pre-treatment had a good texture, and their hardness decreased to approximately one-half of those without the pre-treatment, and their oil content increased by about 15-20%. Adequate deep-fat frying temperature for blanched and frozen strips was about 140°C. "Clean-up-to" (commercial food additive) effectively prevented discoloration caused by oxidation of polyphenols when sweet potatoes were cut into strips. Moreover, the appearance of Imo-karinto was improved by blanching in a boiling solution of disodium dihydrogen pyrophosphate.

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A brief survey on the microbial spoilage of Konnyaku (a traditional gel food in Japan made from konjac mannan) and on the factors affecting the spoilage was carried out in advance of the study on microorganism control of Konnyaku manufacture. Total microbial count was predominantly used as an indicator of the spoilage in this work. The count for Konnyakus on the market was in the range of 0-1.1×10³/g. The level of spoilage was reduced by prolonging the storage period and elevating the temperature. The count for Konnyaku paste (prepared by dispersing konjac flour and pulverized algae in water), which was practically responsible for those of raw materials at the begining (10³/g), increased with the progress in processing until just before the alkali treatment (10⁴×10⁶/g). The increment was mostly attributed to the microbial spoilage of the apparatus such as pumps used for feeding of Konnyaku paste. The count decreased remarkably by addition of alkali and considerably by heating (10¹-10³/g). The spoilage level of konjac flour and pulverized algae were in the order of 10³/g and 10⁶/g, respectively, both including the heat-resistant microbes approximately 10% of the count. The pulverized algae, in addition, was considerably spoiled by coliform organisms. The results showed that the microbial spoilage of Konnyaku is largely attributed to those of feeding pump and pulverized algae. It is, therefore, necessary to establish a useful method for reducing the microbial spoilage of them from the hygienical and preservative viewpoint.

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