In previous papers, we have studied the flow behaviors and the equations of sugar and salt solutions etc. by using a newly designed capillary tube viscometer. In this paper, the viscosity and the density of eight vegetable oils (soybean, rapeseed, corn, peanut, sesame, coconut, cottonseed and olive oils) and salad and frying oils were measured at 10-60°C by using the tube viscometer and a picnometer. The viscosity and the density equations respected to temperature were expressed as following empirical equations; K=a exp(b/T³), ρ=a+bT where, K: viscosity (g/cm·sec), ρ: density (g/cm³), T: temperature (°K). The parameters a and b were calculated by using a nonlinear and a linear least square methods, respectively.

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In order to establish a quality control technique for a local pickle, AKAKABUZUKE in HidaTakayama district of Gifu prefecture, changes in chemical components, color saturation in CIE notation and microbial flora of AKAKABUZUKE during the manufacturing process were investigated. The following results were obtained. 1. The best quality of AKAKABUZUKE was obtained at about 160 days after pickling as judged by several chemical components color saturation and sensory tests of fermented products. After that, over-fermentation and putrefaction proceeded rapidly. 2. The fermentation of AKAKABUZUKE proceeded normally at 5°C-10°C, but did not proceed below 5°C in winter. Putrefaction of AKAKABUZUKE occurred over 10°C at the final stage. 3. At the early stage of fermentation, lactic acid increased along with the disappearance of malic acid which was a main organic acid component of red turnips. At the late stage of fermentation, glucose and fructose decreased whereas lactic acid, ethanol and mannitol increased. In the case of putrefaction, lactic acid, sugars and amino acids decreased rapidly and fatty acids such as acetic, propionic, butyric and isobutyric acid and ammonia which were responsible for heavy putrefactive smell were produced. 4. Lactic acid bacteria grew both at the early and the late stage of fermentation. At the late stage, non-film yeasts grew remarkably and made the liquid turbid. However, thereafter, these yeasts died out rapidly. Growth of aerobic bacteria was observed at the putrefactive stage.

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Interactions between the fish protein and isolated soy protein (ISP) were studied on the basis of heat-induced gel forming property of the mixed systems composed of both proteins. Mixed geis were prepared by heating (90°C, 30min) the homogenized mixtures of the fish paste ("Surimi") and ISP in the presence of 3% NaCl, and when the breaking strength for the mixnd gel deviated from the expected value calculated from those for individual components based on the mixing ratio, this was taken as evidence for the presence of the interactions. As a result, the interactions were dependent on both the protein concentration and mixing ratio of the fish paste to the ISP in the mixed system; below 13% in protein concentration, the synergistic interactions were observed and the deviation in breaking strength from the expected value reached maxmum at the mixing ratio of fish paste to ISP 3:2, e.g., at 11.0% in the protein concentration and this mixing ratio, breaking strength of the mixed-, fish paste-, and ISP-gel were 130, 78.8, and 20.0g respectively. This increase in gel strength caused by mixing both protien materials, that is, the synergistic interaction was interpreted to be related to the promotion in the network formation leading to the building-up of rigid gel body.

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The absorption spectra and the difference spectra of the polyphenol (PP) solution of immature fruit of satsuma mandarin (Citrus unshiu, Marc.) in visible and UV regions of wavelength (230-560nm) were measured during the browning reaction by its polyphenol oxidase (PPO). During the reaction, optical density of the PP solution increased in visible region, showing maximum increment at 375nm. In UV region, optical density of the solution decreased and remarkable diminution was observed in 300-330nm. PP was separated into four fractions (FI-FIV) by DEAE-cellulose chromatography. The absorption spectra and the difference spectra of the reaction mixtures were estimated on the various model systems using PPO-DEAE-cellulose fractions and PPO-phenolic compounds. In the case of browning of pyrogallol and gallic acid solutions, optical density of the reaction mixtures increased both in UV and visible regions. The notable increase of optical density of these systems were seen in 300-330nm. In the systems of PPO-chlorogenic acid and PPO-caffeic acid, optical density of the reaction mixtures increased in visible region and maximum increments of optical density were found at 400 and 375nm, respectively. In UV region optical density of the reaction mixtures dropped, showing remarkable decrease in 300-330nm and 290-310nm, respectively. In the case of the DEAE-cellulose fractions, only FIV fraction was oxidized by PPO. Absorption spectrum of this fraction was very simillar to that of chlorogenic acid. The difference spectra of the system of PPOFIV were in good agreement with those of the systems of PPO-chlorogenic acid and PPO-PP. From the above results, it is suggested that the browing reaction of immature fruit of satsuma mandarin is due to the oxidation of chlorogenic acid or its analogues by PPO.

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Lipid and fatty acid compositions of the total lipids in three parts (fleshy pericarp, stony pericarp and seed) of ume apricot, (Prunus mume SIEB. et ZUCC.) during development, maturation and processing of fruit were studied by means of thin-layer chromatography and gas-liquid chromatography. The total lipid content in seed was predominant, compared to other two parts. Total lipid contents in fleshy and stony pericarps slightly decreased (0.3→0.2%, 0.6→0.2%) during development and maturation, while that in seed increased (0.6→22.7%) considerably in the same period. Main fatty acids of the total lipids in fleshy and stony pericarps were 18:2, 18:1 and 16:0 acids, and those in seed were 18:2, 16:0 and 18:3 acids. During development and maturation, the 18:2 acid content decreased, and the 16:0 and 18:3 acid contents increased in fleshy and stony pericarps. On the contrary, in the same period, the 16:0, 18:2 and 18:3 acid contents decreased and the 18:1 acid content increased remarkably in seed. The total lipids in seed were consisted of 7 classes (triacylglycerols, 1, 2-diacylglycerols, free sterols, fatty acids, compound lipids, sterol esters and 1, 3-diacylglycerols) and the main component was triacylglycerols. A remarkble increase of triacylgycerols in seed (24.1→93.3%) was observed with decreases of other lipid classes during development and maturation. Main fatty acids of triacylglycerols in seed were 18:2, 18:1 and 16:0 acids. Saturated fatty acids were found more often at 1 and 3-positions than at 2-position of triacylglycerols. In fatty acid compositions of triacylglycerols and its 2-position, 16:0, 18:2 and 18:3 acid contents decreased while 18:1 acid content increased during development and maturation. Main molecular species of triacylglycerols in seed in late stage of maturation were UUU (74.1%. OLO, OOO and others) followed by SUU (13.0%) and UUS (10.5%). Free strols and sterol esters in mature seed were consisted of sitosterol, campesterol, stigmasterol, cholesterol and isofucosterol and main component was sitosterol.

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The turbidity of canned mandarin orage syrup is due to precipitation of hesperidin. By screening test of natural materials for prevention of turbidity, it was found that the addition of β-cyclodextrin increases the solubility of hesperidin and prevents the precipitation of hesperidin in the model syrup. In this paper, canned mandarin oranges added with β-cyclodextrin were prepared at 4 factories in the industrial scale, and were stored at room temperature for one year. It was found that by the addition of β-cyclodextrin, the amount of souble hesperidin in syrups were increased and precipitated hesperidin were decreased. It was also confirmed that the syrups of canned mandarin orange were kept to be clear in the presence of β-cyclodextrin. The effective additional concentration of β-cyclodextrin is 0.1-0.4% in poured syrup. The amounts of fruits and the quality of fruits such as appearance, flavor and texture were not altered by the addition of β-cyclodextrin.

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Wasabia japonica root pieces were dried at below 55°C. Wasabi flours were stored in sealed vessels, and isothiocyanate (itc) contents in the hydrolysates of the flours were determined by headspace analysis during the storage. When the flours were stored at 20°C and 30°C, the contents of iso-propyl, sec-butyl, n-butyl, allyl and 3-butenyl itcs all decreased, especially at 30°C storage, the amount of iso-propyl itc reduced by half after 1 week, and those of the other itcs had the same results after 4 weeks. In Wasabi flours which had the decreased itc contents, these contents was restored by the addition of trace amount of L-ascorbic acid as myrosinase activator. Wasabi flour with low itc contents and horseradish flour were mixed at several ratios to prepare so called "Wasbiko". Several itc contents and mixing ratio bore good correlation curves. Accordingly, mixing ratio of Wasabi flour and horseradish flour in the "Wasabi-ko" will be assumed similar to the case of "Wasabi" powder (so called "Kona-wasabi") by the calculation of Rg, x and y values.

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In the previous paper, we have studied on the over-all drying-rate equations. In this paper, we studied on the drying-shrinkage and rate equations of root vegetables. The empirical dryingrate equations were postulated as follows. dx/dθ=knS(1-x)ⁿ S=S₀(-ax+1)^2/3, x=(w₀-w)/(w₀-w_e) For drying-shell model: α=1-w_eρ₀/(w₀ρ₀) For uniform drying model: a=1-{(w_e/ρ_e)/[(w₀-w_e)/ρH+w_e/ρ_e]} where, x: drying ratio (-), θ: drying time (min), S, w and ρ: surface area (cmcm²), weight (g) and density (g/cm³). Subscripts H, O and e: water, initial and equilibrium states. These calculated results agreed with the observed values.

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The drained water from steaming of soybean in Natto (fermented soybean) processing contains valuable components in high concentration, as the soybeans are steamed under drastic conditions of 120°C for 30-40 minutes. The efficacy of ultrafiltration for their recovery was studied from the standpoint of utilization of waste water as natural resources. lt was impossible to ultrafiltrate directly the drained water by the DDS plate-and-frame module used in this study, because of the high viscosity of the drained water causing a large pressure drop. Therefore, in order to remove the viscous components, this water was treated with isoelectric point sedimentation. The pH of the drained water was adjusted to 4.1-4.3 with hydrochloric acid followed by centrifugation. However, the separation ratio (supernatant volume/drained volume) was not satisfactory. Freezing of the pH adjusted drained water was effective in improving the separation ratio. The supernatant was subjected to ultrafiltration using three membranes of different nominal cut-off molecular weight. lsoelectric point sedimentation was greatly effective in reducing viscosity of the drained water, but was sligthly effective in reducing the BOD (93000ppm). BOD of the ultrafiltrate was 52000-68000ppm, which depended on the performance of the membrane. These treatments results in a 27-46% reduction of BOD from the drained water.

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In order to recover valuable components from the waste water drained from steaming of soybean in Natto processing, operating conditions of ultrafiltration of the supernatant from isoelectric point sedimentation, including washing of the membrane to maintain membrane performance, were studied. Using the DDS plate-and-frame module with three different kinds of ultrafiltration membrane (GR 50p, 61p and 81p), the supernatant was recirculated, and the variation of permeation flux with various flow rates (2-81/min), pressures (2-10kg/cmcm²) and pH (2-10) was examined. At the operating condition when flow rate was 6.61/min, pressure 3kg/cmcm² and temperature 60°C, the permeation fiux of GR 50p, 61p and 81p membranes were 6×10^-4ml/cmcm²·sec (5201/mm²·day), 4×10^-4ml/cmcm²·sec (3451/mm²·day) and 3.6×10^-4ml/cmcm²·sec (3101/mm²·day), respectively. The permeation flux of GR 50p membrane was much better than that of the other two. GR 61p and 81p membranes showed similar performance in ultrafiltration of the supernatant, whereas GR 50p showed different performance in spite of the fact that GR 61p and 50p membranes showed similar permeation flux for pure water. All membranes used in this study were made from polysulfon, but the characteristics (pH range, chemical and pressure tolerance) of GR 50p were different from those of the other two. These results suggested that the nature of the deposit changes by the membrane characteristics other than permeation flux for pure water. Restoration of permeation flux of higher permeability membrane washed under the same flushing conditions is lower, since on such a membrane, the amount of the deposit is larger and the concentration is higher. However, by washing with 0.5% Henkel's detergent solution (VR-2604-20) for 30 min, the original permeation flux of the membrane could be recovered.

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The turbidity of canned orange syrup is due to the precipitation of hesperidin. Various natural materials was investigated to prevent the turbidity in the canned mandarin orange syrup. It was found that the solubility of hesperidin in the model syrup increased by the addition of β-cyclodextrin (β-CD), which was cyclic oligosaccharide composed of 7 glucose units with α-1, 4 linkage. The mechanism of the solubility increase was studied by proton nuclear magnetic resonance. It may be concluded that β-CD formed an inclusion complex with hesperidin by including the phenolic group of hesperidin in the cavity from the H-6 side of β-CD.

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