Supercritical carbondioxide (SC-CO₂) extraction was applied to a constructed citrus peel oil. The extraction conditions were as follows: extraction pressure; 75-200atm, extraction temperature; 35-60°C. (1) Under a constant temperature, the solubility of peel oil components into SC-CO₂ increased from 0.5% to 11.5% with pressure. As the temperature increased, however, the solubility was decreased from 3.4 to 1.1% 100atm, but increased from 3.5 to 11.5% above 120atm. (2) Limonene was selectively extracted under the following conditions: below 80atm at 35°C, 90atm at 40 and 50°C, and 100atm at 60°C. The solubility was less than 1.1% in all the cases. (3) BWR (Benedict-Webb-Rubin) equation of state was applied to experimental data in order to reveal PVT relation in SC-CO₂ phase. (4) At 35 and 40°C, limonene could be extracted selectively under the compressed state less than its critical molar volume, but at higher temperature, limonene was extracted selectively only under larger molar volume than the critical one.

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Staling mechanism of bread has not been fully understood due to its complexity although numerous studies have been reported on the effects of raw materials and condition of making bread on bread staling. This causes some difficulties for comparing experimental data for bread staling with each other. In this study, the role of shortening (oils and fats) and monoglyceride on staling was investigated for white bread made by the straight dough method. In order to elucidate staling mechanism more precisely, the sample breads were stored in the conditions preventing evaporation of water in them. The results are summerized as follows: (1) Oils and fats acted gluten network through emulsifiers in the dough, making gluten structure fine and thin. Then, the crumb structure also became fine and thin, which caused increase of the loaf volume and reduction of bread staling. (2) Monoglyceride had two functions. One was the same as oils and fats, and the other was reduction of starch gelatinization and retrogladation of gelatinized starch.

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Oligosaccharides production on presence of maltose as glycosylacceptor by dextransucrase of Streptococcus bovis No.148 isolated from bovine rumen was investigated. Oligosaccharides produced by S. bovis dextransucrase were in agreement with those produced by Leuconostoc mesenteroides NRRL B-512 on the paper chromatogram. The trisaccharide (MG-1), the tetrasaccharide (MG-2), and the pentasaccharide (MG-3) was identified as 4-α-isomaltosyl-D-glucose, 4-α-isomaltotriosyl-D-glucose, and 4-α-isomaltotetraosyl-D-glucose, respectively. The oligosaccharides production was influenced by the presence of certain salts. Cobaltous chloride stimulated the MG-1 production, while depressed the MG-3 production. Calcium chloride and CuSO₄ depressed the MG-1 production, and stimulated the MG-3 production. Influence of maltose as acceptor on the oligosaccharides production was examined on the reaction mixture of 5% sucrose. It was found that the pattern of oligosaccharides production was controlled by the change of molar ratio of sucrose and maltose. When the molar ratio of maltose per sucrose was lower than 0.05, MG-3 and higher DP of oligosaccharides were produced. On the other hand, when the molar ratio was higher than 1.0, MG-1 was produced mainly. The calculated yield of MG-1 for consumed sucrose was about 78% of the molar ratio of maltose per sucrose at 4.0.

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Three types of natural salt and 12 types of saltmixtures (prepared by adding MgSO₄, MgCl₂, CaSO₄ and KCl to NaCl at levels of 2, 4 and 8%, respectively) were used to study the effect of microcomponents in salt on the processing properties of muscle protein. The extractability of muscle proteins and myosin heavy chain increased with the increasing the amount of microcomponents in natural salt, and MgSO₄, MgCl₂ and CaSO₄ in salt mixtures. These changes tended to correspond with that of the ionic strength of each salt solution used. Furthermore, the extractability of myosin heavy chain especially increased with CaSO₄ in salt mixture. Heat gel strength of myosin B also increased depending on the amount of same microcomponents in salt described above, and even more noticeable with the increase of heat temperature. Scanning electron micrographic observation showed that salt composition did not affect the ultramicrostructure of mysoin B gel formed at 40°C and 80°C for 30 minutes. When cured pork loin, cooked pork loin and bologna sausage were manufactured using natural salt and salt mixtures in this experiment, no effect of salt composition on water holding capacity and color of these meat products was observed. On the other hand, hardness of bologna sausage manufactured with salts which contribute to the increase of protein extractability and heat gel strength of myosin B tended to increase; particularly, the increase of hardness was significantly high in salt mixture with CaSO₄. Sensory evaluation of meat products showed that taste of cured pork loin became more mild with the increase of microcomponents in natural salt and MgCl₂ in salt mixture and better aftertaste with the increase of MgSO₄, MgCl₂ and CaSO₄ in salt mixtures. But there was no effect of salt composition on hardness of cured pork loin and cooked pork loin and taste of cooked pork loin and bologna sausage. These results suggest that microcomponents at levels of 2% to 8% in salt show the possibility contributing to the increase of hardness of meat products with out undesirable effect on their color and taste.

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In order to develope a new automatic control in the coagulation process of soymilk, the electric conductivity changes in a 1l coagulating reaction vessel were continuously measured by a combined personal computer. A steady addition of 1M calcium chloride to soymilk at 60°C linearly increased the electric conductivity to bring a flexed line. In other words, the loci of that reaction were expressed by two straight lines of different slopes, and the intersection, or the break point (X (ml), Y (mS/cm)), could be simultaneously visualized. Hereafter, the value of X ml at the break point named "Point of critical concentration of coagulant". The value of X ml showed a steady shift with the increased concentration of soymilk. But, neither the added pottasium chloride nor the added sucrose affected to that value. It was considered that the computerized measurement of electric conductivity was promising for process control of coagulating reaction between soymilk and calcium chloride.

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The relationship between the"Point of critical concentration of coagulant", Xml, in the electric conductivity measurement for soymilk and the corresponding phase changes in solidification of the coagulated products during the experimental"tofu"processing were investigated. A series of the handmade acryl plastic molders having cylindrical form were devised and used for the experiments with series of soymilk from three soybean varieties. A few selected parameters which would indicate the optimum end points of coagulant in solidification processes for tofu were adopted. These were‘transparency (or, turbidity) of whey’, ‘height of pressing tofu’ and ‘hardness of tofu’. And these parameters was found to come at such concentration levels of the coagulant, calcium chloride, more or less over the X-values. Each of them well correlated with X-value, respectively. It was concluded that the X-value could be an effective indicator for process control of coagulating reaction of soymilk and solidification process for tofu.

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The squid meat cured in sake lees have peculiar texture. Changes in the texture and the proteins of squid meat cured in sake lees were studied by physical and chemical methods and sensory tests as well. The squid meat was cured in sake lees after being water-boiled for a few minutes and peeled the two surface layers of the skin. Changes of the meat texture during 10 day curing were investigated by sensory tests and by a texturometer and a rheometer. The proteins of squid muscle preserved with sake lee extract were analyzed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). The sensory tests revealed that sake lee cured squid meat became tender as it is easily bit off with teeth. The hardness and the tensile strength of squid meat cured in sake lees decreased with the length of curing time. The SDS-PAGE patterns showed that the proteins of squid muscle preserved with sake lee extract were decomposed to fragments with lower molecular size, while the decomposition didn't occur when the sake lee extract was cooked prior to use. These results suggested that the decrease of hardness of squid meat during sake lee curing is attributable to the decomposition of the proteins caused by the enzymes in sake lees.

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Lipids, carotenoids and chlorophylls, which constitute an important component for nutritive value, quality, storage and production, of vegetables, have been investigated from the flower heads of four cultivars of field grown broccoli. Sites of the edible part of the flower heads of broccoli were in the range of 128-173g in weight, with the highest value being for Isomidori cultivar. Total lipid and fatty acid, carotenoid, and chlorophyll contents of four cultivars of broccoli ranged from 880-980mg, 390-440mg, 3.31-4.92mg and 31.9-42.2mg per 100g fresh weight, respectively. Lipids had a large concentration of polyunsaturated fatty acids, indicating that broccoli is a rich source of ω-3 unsaturated fatty acids in vegetables. Differences in the fatty acid composition of the lipids were not significant among the four cultivars. Isomidori cultivar was found to have a notably high contents of lipids, fatty acids, carotenoids and chlorophylls.

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Dried radish chip extracts (CE) were analyzed for their effective utilization to food industry with two samples. (1) CE contained considerable amounts of sugars as much as 33%. Glucose, fructose and sucrose comprised 87% of total sugars. (2) As for free amino acids, glutamic acid, aspartic acid and alanine which are concerned with food taste were major amino acids. (3) Considerable amounts of nitrates which are remarkably effective for the improvement of meat color were detected. These results suggested that CE are very useful as food seasonings and for quality improvement of meat products.

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Eight major inorganic ions, Na⁺, K⁺, Mg²⁺, Ca²⁺, Cl^-, NO₃^-, SO_42- and HCO₃^-, in 44 commercial mineral water products, 7 city waters and 3 well waters were analyzed by ion chromatography. SiO₂ was also measured by the molybdenum blue method. The relationship between inorganic components and flavor was examined by sensory evaluation. (1) There were differences in the compositions and the contents of inorganic components among samples. The averages of total inorganic components of Japanese mineral water products, imported nongas type mineral water products, imported gas type mineral water products, city waters and well waters were 153, 322, 1856, 189 and 175ppm, respectively. The imported gas type ones were rich in the content of HCO₃^-. Not much difference in the composition of inorganic components was found among Japanese mineral water products, city waters and well waters. (2) Sensory evaluation elucidated that a factor governing the flavor of the drinking waters was the smell of musiness and residual chlorine rather than the inorganic components.

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To know the contamination level of metals from oilseed into vegetable oils; the nickel and other heavy metal contents in 16 species of oilseeds (92 samples), and 19 species of vegetable oils (77 samples) were measured. Nickel was detected in all oilseeds, and its average content was above 3ppm in soybean and walnut, and above 2ppm in cottonseed, perilla seed and Japanese torreya nut, while below 0.5ppm in corn. The content of iron was the highest in perilla seed (X: 710.7ppm) and the lowest in Japanese torreya nut (X: 27.2ppm). The copper content was the highest in sesame seed (X: 17.0ppm), and the lowest in corn (X: 1.68ppm). In edible vegetable oils, on the other hand, nickel was detected only 0.05ppm or less in all samples, despite of including some oils produced without refining (deacidification, bleaching and deodorizing) process. The contents of iron and copper in the oils were 3.96ppm or less and 0.09ppm or less, respectively. Besides, lead was detected 0.1-0.5ppm in only a few samples of several species of oilseeds, but not detected in all of the edible vegetable oils, while arsenic was not found in all samples. These results suggest that nickel and other heavy metals, contained in an oilseed, might hardly be remained in each edible oil.

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In previous papers, it has been reported that the bitterness due to limonoid of citrus products decreased by addition of β-cyclodexkrin (β-CD). However, in the case of canned Iyo orange segments in syrup, the addikion of β-CD caused heavily white precipitation in the syrup. The cause of the precipitation was concluded to the formation of inclusion compounds of β-CD with ingredients of juice sac membrane of Iyo orange and to the poor solubility of those inclusion compounds in the syrup. This paper describes effects of addition of Maltosylβ-CD formulation (M-β-CD), which has 150 times solubility more than that of β-CD in water, on the bitterness reduction of syrupped Iyo orange segments in comparison with β-CD. The drained weight of segments decreased as the additional amount of β-CD or M-β-CD in the syrup increased. But, compared with that of the control group, decreasing ratios were less than 2.5% in average. In the syrup of 0.4% β-CD group, heavily cloud and precipitates were recognized after 1 month storage. On the other hand, in the M-β-CD groups, no cloud or precipitate was formed even in 0.5% M-β-CD added group. As results of a sensory evaluation test, it was appreciated that the bitterness of Iyo orange segments reduced remarkably by adding 0.4% of β-CD or 0.4-0.5% of M-β-CD in syrup. The most favorable taste was recognized in 0.5% M-β-CD group and the next was 0.4% β-CD group. Thus, the limonin content of canned Iyo orange segments reduced by β-CD or M-β-CD addition and these results also agreed with the results of the sensory evaluation test of segments taste.

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OMURA et al. manufactured the emulsified product from sardine fillet. The consistency of their product was softer than that of commercial mayonnaise and the limit in the storage period was about 10days. To improve these imperfections, the effect of the removal of lipid from sardine meat was investigated. We produced a new emulsified product from sardine meat preparation with very low lipid content. As the soybean oil content increased, the dynamic rigidity G′ and dynamic loss G″values of the product increased. The increase in the viscoelasticity could be explained by the fact that the firmer consistency was created as the structure of emulsified product became similar to the closest packing. The viscoelasticity of our products with the soybean oil ratio of 1.64 and 2.46 to sardine meat was almost equal to and larger than that of commercial mayonnaise, respectively. Our products with the vinegar ratio of 0.14 and 0.21 to sardine meat showed higher G′ and G″values than those of commercial mayonnaise. In these products, both G′ and G″remained almost unchanged for 4weeks of cold storage. Therefore, it is considered from the consistency and stability evaluations that these products are superior as a dressing-type food to OMURA'S. In the sample with the vinegar ratio of 0.07, the G′ considerably and G″to some extent decreased during the storage. When NaCl content was high, the G′ and G″values of the sample increased but the consistency became unstable. The G′ value decreased during the storage up to 1week. As to NaCl, the product with low content (the ratio to sardine meat is 0.021) was suitable.

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