The influence of sodium chloride on the development of bitter taste in soybean miso was investigated by sensory tests of water soluble (W-S) and butanol soluble fractions (Bu-S) from non-salted soybean miso, soybean miso and Hatcho miso.
1) Bitter taste was developed by W-S solution of non-salted soybean miso (100mg/ml), the W-S solution desalted down to 0.02%(100mg/ml) and hydrophobic amino acids (each 100mg/100ml). Those bitter taste was suppressed by adding not less than 0.25% sodium chloride.
2) The strongly bitter taste in Bu-S of several kinds of soybean miso (10mg/ml) and W-S solution of non-salted soybean miso (100mg/ml) was suppressed by adding 1% sodium chloride.
3) The bitter taste of hydrophobic amino acids (each 100mg/100ml) was suppressed by adding not less than 0.25% sodium chloride, glutamic acid (100mg/100ml) or aspartic acid (100mg/100ml), but the inhibitory action of glutamic acid was superior to aspartic acid.
4) From these results, it was considered that the bitter taste of bitter amino acids and bitter peptides in non-salted soybean miso was strengthened as a result of the deficiency of sodium chloride.

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The production conditions of twin-screw extruded defatted soybean meal (TSE-DSM) for soy sauce were determined, and the advantages of the produced TSE-DSM in commercial soy sauce production were evaluated. By using TSE-DSM, the total nitrogen utilized ratio was improved by 10% or more, the pressing efficiency of "moromi" mush was raised by 10%, and the amount of remaining pressed residues (soycake) was decreased by 16%, compared to the values obtained using defatted soybean meal (DSM) that is generally used for soy sauce production. Furthermore, the amounts of constituents remaining in each soycake were compared, and the amount of nitrogen in the soycake from TSE-DSM was found to be 1.56% less that obtained using DSM. Therefore, TSE-DSM is more efficient than DSM owing to higher total nitrogen utilized ratio and less amount of remaining soycake in commercial soy sauce production.

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The present study was performed to identify the substance(s) responsible for the generation of large amounts of ethanal when mackerel muscle was heated in the presence of potassium bromate. The experimental results revealed that lactic acid was one of such substance. Almost no ethanal was generated when lactic acid was heated in the presence of potassium bromate alone ; further addition of ascorbic acid to lactic acid in the presence of potassium bromate was necessary to generate large amounts of ethanal. These results indicate that ascorbic acid acts as an accelerator of ethanal generation from lactic acid. However, as the ascorbic acid content of mackerel muscle is relatively low, other substances with an action similar to ascorbic acid must be present in the muscle. On the other hand, 2-hydroxy-n-butyric acid generated large amounts of propanal when heated in the presence of potassium bromate and ascorbic acid. In these reactions, therefore, it was considered that a-hydroxy-carboxylic acid generated a carbonyl with one carbon atom less than the original compound.

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The effects of various smoking conditions, especially temperature, relative humidity and smoke density on the quality of Katuo-bushi were investigated. The smoke absorption rate by bonito has been found to increase with the smoke density and to decrease with the smoke velocity. There was no clear correlation between smoke house temperature and relative humidity on smoke absorption of bonito. In the new method of continuous smoking, the cut and boiled bonito meat were continuously dried to harden after the conventional smoking of 2 times repetition. The conditions for the new drying process were 40°C for 2 hours as the first and 50°C for 2-5 hours as the second step. Subsequently cooled until 30°C for 5-7 hours under relative humidity of 80% at 30°C. The amounts of smoke particles (<0.3μm) was about 3-4× 108 per 100ml in smoke house gasses. Air flow rate was 0.2-0.5m/s. This smoking programs were repeated 24 times. The manufacturing term was reduced to one-half by continuous smoking process compared with the conventional smoking process. It was not necessary to take out the Katsuo-bushi from a smokehouse, resulting in the reduction of manual labour. Katsuo-bushi were more effectively and uniformly dehydrated using the continuous smok-ing process. The smoke absorption was sufficiently achieved by this process.

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When itohiki-natto becomes old, white crystal develops on its surface and a food feeling gets extremely worse. We examined the crystal formation under liquid cultivation for the purpose of quality maintenance of itohiki-natto. After natto bacilli, Bacillus subtilis (natto) KFP 419 was cultivated in NBP medium which contained 1.0% beef extract (Difco), 1.0% phytone (BBL) and 0.5% sodium chloride, pH 7.0 and was stood at 4°C, a kind of colorless crystal was found to form. Since the crystal was composed of magnesium, phosphorus, ammonia, and the same crystal was obtained by crystallizing the marketed struvite powder, it was determined to be magnesium ammonium phosphate, namely struvite. The crystal separated out specially from the culture at 30°C for 4 days in NBP medium. The crystal did not formed in the medium, unless the strain was inoculated even if the initial pH of the medium was changed. Therefore it was proved that ammonia, one of the metabolite, magnesium and phosphorus in the medium, and especially magnesium, were responsible for crystallization. The crystallization did not occur without refrigeration at 4°C, but the crystals, once formed, did not dissolved even standing at room temperature.

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The content of polyphenols, anthocyanins, and flavonols in petal extracts were determined spectrophotometrically in 95 kinds of flower petals, and the antioxidative activities of the petal extracts were examined by the decoloration of IR-carotene coupled with the oxidation of linoleic acid. The polyphenol content for each family of flower showed some differences in mean levels, i.e., 8.74% in Theaceae (camellia), 4.78% in Rosaceae (rose), and 1.66% in Compositae (chrysanthemum), which were calculated as gallic acid in 100 g dry matter of petal. The highest content was found to be 14.83% in red Rosa hybrida (Rosaceae). Almost all of the petal extracts showed antioxidative activity, and good correlation between the activity and the level of polyphenol content was observed, suggesting the direct contribution of polyphenols in the antioxidative activity. The highest ob- served in the red Rosa hybrida was as high as 10 times that of BHA. Further examination of correlation of the kind of polyphenol component and genus of family of flower indicated that the activity of the petals of red Rosa hybrida (rose genus) correlated with their anthocyanin content and activity of Compositae (chrysanthemum family) with the flavonol content.

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An excessive supply of vitamin D₂-fortified shiitake mushroom was continued for a long period in laying hens to examine the stability of producing vitamin D-fortified eggs and safety to the hens. Vitamin D₂-fortified shiitake mushroom containing 80μg/g vitamin D₂ was added to diets at 0, 0.25, 0.5, 1.25 and 5% levels, respectively, and were fed to White Leghorn for 30 weeks. The content of vitamin D₂ in the egg yolk increased until the 6th or 8th week and then reached a plateau. Laying hens constantly produced vitamin D-fortified eggs for 30 weeks. The content of vitamin Din the egg yolk was proportional to the level of fortified shiitake mushroom added. Vitamin D content of the egg yolk on the 5% diet was 62μg/g, 125 times higher than that on the control diet. The content of 25 (OH) D₂ in the egg yolk showed the similar trend to that of the vitamin D content in the egg yolk, and increased proportionally to the levels of vitamin D₂-fortified shiitake added. This experiment suggested that 25 (OH) D₂ could be easily obtained from eggs. Vitamin D and 25 (OH) D₂ also seemed to be accumulated in chicken liver and meat. Comparing the amounts of vitamin D in various tissues of hens, leg muscle rich in fat contained 0.38 μg/g, which was 5 to 6 times higher than that of the breast muscle and pectoral muscle. An excessive supply of vitamin D₂-fortified shiitake mushroom did not affect the performance of laying hens, egg shell quality and concentrations of calcium and phosphorus in the serum. The health status of laying hens was good as well except for an inflammatory kidney on the 5% diet.

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Gelation of globin using pepsin, chymosin, papain, ficin or trypsin under various treatment conditions [1 : 32 000-1 : 125 (w/w) of enzyme to substrate (E : S), pH 2.0-8.0 and 40°C for 24 h] was investigated by determination of gel strength and degree of hydrolysis (DH) and by SDS-polyacrylamide gel electrophoresis (SDS-PAGE).
1) Globin gels were formed by pepsin in thepH range of 2.0-4.0. The optimum pH resulting a strong gel was pH 3.0. On the other hand, globin did not set to gel by any other protease treatments.
2) When globin was treated with pepsin of each E : S (1 : 32 000-1 : 125), the gels were formed at any pepsin concentrations. A maximum gel strength was obtained at the treatment with pepsin of 1 : 8 000 (E : S) which showed the DH of 2.7%. Chymosin, papain and ficin did not form any gels in spite of the same DH (2.7%).
3) SDS-PAGE patterns suggested that pepsin treated globin had some peptides which were different from those produced by any other protease's treatment qualitatively.

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A mixture of Japanese apricot ume (Prunus mume Sieb. et Zucc), white liquor and sugar is well known to form an ume liqueur, after standing at room temperature in a dark for three months, by the end of which time most of the sugar has been inverted to glucose and fructose. In order to elucidate its mechanistic aspects, the inversion process was studied on three kinds of liqueur preparations ; an ume liqueur stored at room temperature in a dark (a conventional preparation), an ume liqueur heated at 60°C for 36 hrs (a preparation by an "instant" liqueur maker), and a liqueur with added citric acid (pH 2.0 to 4.0) instead of ume (a preparation without enzyme). On the basis of the properties of ume invertase reported before (pH optimum at 3.0, Km 4.0 × 10-2, and noncompetitive inhibition by ethanol), it is concluded that the inversion of sugar in a conventional liqueur (pH ca. 3.0, ethanol concentration 35 to 20%) proceeds by ume invertase, that the inversion in an instant liqueur is predominantly acid-catalyzed, and that the inversion catalyzed only by citric acid at pH 3.0 is slow and hence ten times as much proton concentration is required for this preparation to approach the comparable rate to that by the invertase. The invertase activity of fresh ume fruit was 1.6×10-1 μmol/g·min. By previously heating fresh ume at 60°C in white liqueur for 12 hr or more, the invertase activity was lost completely, but about 10% of it remained by heating for 6 hr.

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The purple-colored sweetpotato juice containing anthocyanin pigments was prepared from "Ayamurasaki", and the reduced effects on carbon tetrachloride-induced liver injury of rats were studied. The pretreatment with purple- colored sweetpotato juice orally for 5 consecu- tive days prior to carbon tetrachloride treatment effectively reduced in GOT, GPT, LDH and thiobarbituric acid-reactive substance (TBARS) in serum and liver TBA-RS and oxidized protein levels. These results demonstrated reducing effects of purple-colored sweetpotato juice against carbon tetrachloride-induced liver injury.

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This paper dealt with the relationship between softness of fruits and changes of pectic substances during the ripening of strawberry fruit"Hokouwase" Four pectin fractions were separated by sequential extraction from AIS into WP with water, PP with hexametaphosphate, HP with hydrochlo-ric acid and KP with potassium hydroxide. The results obtained were as follows. 1) The total amount of galacturonic acid in four separated pectin fractions decreased with ripening of strawberry fruits. 2) WP which was little in immature stage increased with maturation. On the other hand, HP which was the most abundant in immature stage decreased to the same amount of WP at a ripe stage. 3) WP, PP and HP were the high-methoxyl pectins throughout the maturation. 4) The molecular weights of four separated pectin fractions were estimated by Cellulofine gel permeation chromatogra-phy, that is, WP, PP had 1000000, HP had 300 000 and KP had 10000 in immature stage. However these molecular weights were tend to lower with the maturation. Especially, the molecular weight of HP was lowered to 250000 in a greenish-white stage and to 100000 in a ripe stage.

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Differences in mineral components at various portions of apple fruits were investigated with cv. Fuji grown at Morioka Branch, Fruit Tree Research Station in 1979. Nine minerals viz. sodium, potassium, magnesium, calcium, iron, manganese, copper, zinc and phosphorus were determined. The fruits which were used for the experiment in mineral content in different portions were collected from a single tree. The red (sunny side) and green (shaded side) fruits were collected from 3 trees grown on same condition. The concentration of ash, sodium, potassium, calcium, iron, copper and zinc increased gradually from outside (peel) to inside (center) in a fruit, whereas the concentration of minerals in ash unchanged. On the other hand concentration of magnesium and its content in ash gradually decreased from outside to inside. Concentration of ash and potassium, calcium and zinc gradually increased from lower (stalk end) to upper (blossom end) portion. Conversely Brix degree, magnesium content in ash decreased gradually from lower to upper portions of a fruit. There was no change in concentration of manganese in portions of a fruit. There were no significant difference in the concentration of 9 minerals components expressed either in mineral/weight ratio or in mineral/ ash ratio, both in red and green side of a fruit. However the concentration of individual mineral components differed on portions of a fruit. A definite pattern in the distribution of different minerals composition was observed in fruit-stalk, calyx, core, and peel portions of a fruit.

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Thick bean sprouts cultivated using a rotary box (rotary cultivation, RC) have a decreased yield and inferior quality, although the growth of sprouts from the beans is promoted and the nutrient content of the sprouts is improved
Because exposure to high levels of carbon dioxide was useful for promoting the growth of the hypocotyl and increasing the quantity of harvested sprouts, we combined the rotary box method with the CO₂-enriched method Herein the usefulness of this combination method for improving the physical properties and the yield of bean sprouts by controlling hypocotyl growth were examined.

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