Publications by authors named "Shuji Adachi"
Maltose, cellobiose, and lactose dissolved in 0.01 mol/L arginine solution or 0.01 mol/L phosphate buffer (pH 7.
View Article and Find Full Text PDFAqueous galactose solutions containing eggshell was heated at 120 °C to produce calcium supplements containing rare sugars. Galactose was isomerized to rare sugars with improving rare sugar yields compared to those without eggshell. Organic acids were also formed as byproducts during the reaction.
View Article and Find Full Text PDFAccurate clinical staging is important in diffuse large B-cell lymphoma (DLBCL) to adapt to optimal therapy. Splenic involvement of DLBCL has been recently more detectable with the advancement of a diagnostic scan by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT). Our clinical question is whether splenic involvement was adequately diagnosed by FDG-PET/CT imaging.
View Article and Find Full Text PDFIsomerization and epimerization of fructose to glucose, mannose, allulose, and allose were executed using a subcritical phosphate buffer solution to effectively produce useful monosaccharides. The conversion of the substrate and the yield of products were dependent on the reaction temperature, initial pH, initial substrate concentration, and buffer concentration. A high yield of mannose was achieved under the optimal reaction conditions we identified.
View Article and Find Full Text PDFGalactose was treated in sodium phosphate buffer at various concentrations (0.1-500 mmol/L) under subcritical water conditions (140 °C), and the effects of the buffer concentration and reaction time (0-300 s) on the reaction behavior were evaluated. The reaction proceeded rapidly at higher buffer concentrations.
View Article and Find Full Text PDFReaction of glucose or galactose was performed in arginine solution or phosphate buffer (pH 7.0) using a batch reactor at 110°C. The yields of products, pH, and absorbances at 280 and 420 nm were measured during the reaction.
View Article and Find Full Text PDFThis work investigated the isomerization of galactose to tagatose, a low caloric rare sugar, using arginine as a catalyst. Galactose (5 % w/v) and arginine (0.10 mol/mol-galactose) in water were treated at 90-120 °C.
View Article and Find Full Text PDFThe effect of oil-droplet diameter on lipid oxidation in O/W emulsions is unclear, and conflicting results have been reported. These conflictions may be due to different experimental conditions being used, such as the type of oil, the type of emulsifier, temperature, and the range of oil-droplet diameters tested. The method used to evaluate the oxidation could also have varied among studies.
View Article and Find Full Text PDFAlthough betanin is commonly used as a water-soluble red colorant in foods, it is unstable when heated. In this study, the discoloration of betanin in a buffer solution was kinetically studied in the pH range of 2.6 to 7.
View Article and Find Full Text PDFThe major polyunsaturated fatty acids in krill oil extracted from Euphausia pacifica, known as Isada on the Sanriku coast, are eicosapentaenoic acid (EPA) and docosahexaenoic (DHA) acid. A kinetic model was proposed to explain the relationship between the fractions of unoxidized EPA (Y ) and unoxidized DHA (Y ) in the oil spray-dried with maltodextrin and stored at 25, 50, and 70℃. The relationship between Y and Y during storage was independent of the temperature and could be expressed using the proposed model.
View Article and Find Full Text PDFThe solubility of oxygen and its transfer rate to the lipid phase play important roles in lipid oxidation, which affects the taste and safety of lipid-containing foods. In this study, we measured the Henry's constants (solubility) of oxygen for fatty acids, fatty acid esters, and triacylglycerols (TAGs; vegetable oils), as well as the mass transfer coefficients of oxygen at the gas- and water-lipid interfaces. The constants and coefficients were estimated by analyzing the change over time in the oxygen partial pressure or concentration in the closed container based on the mass balance equations of oxygen in the gas and liquid phases.
View Article and Find Full Text PDFGalactose was isomerized in pure water or in 10 mmol/L sodium phosphate buffer at 160 °C under pressurized conditions. The isomerization of galactose to tagatose and talose in phosphate buffer resulted in 14% and 1.4% yields, respectively, which were significantly higher than those obtained in subcritical pure water (0.
View Article and Find Full Text PDFCrystallization of vegetable oil affects the efficiency of the oil-refining process and the quality of foods containing the oil. However, the crystallization of the oil is a complicated phenomenon. The crystallization behavior of rapeseed oil was investigated using differential scanning calorimetry (DSC) at a cooling rate of 0.
View Article and Find Full Text PDFMayonnaise is an oil-in-water (O/W) emulsion containing oil at the weight fraction of about 70%, which is stable for over a year when stored at room temperature. The stability examination of more stable mayonnaise can be time-consuming. Mayonnaise rapidly separates into oil and aqueous phases when water in the mayonnaise evaporates, which increases the ionic strength of the aqueous phase and reduces electrostatic repulsion among oil droplets.
View Article and Find Full Text PDFThe induction period for crystallization, defined as the time required to crystallize, was discussed during isothermal storage at -5 to -45°C for various vegetable oils; olive, safflower, rapeseed, corn, rice bran, soybean, and linseed oils. The induction periods, largely dependent on the oil type and storage temperature, were classified into two groups. The induction periods of corn, rice bran, soybean, and linseed oils were monotonically shortened as the storage temperature decreased.
View Article and Find Full Text PDFPacific krill () contains high amounts of astaxanthin, a carotenoid pigment with strong antioxidative activities. In this study, the effects of subcritical water temperatures (100-180 °C) and times (0-10 min) on color changes (*, *, and *) and astaxanthin degradation in Pacific krill were investigated. In addition, an aqueous solution of pure astaxanthin and that of crude astaxanthin from Pacific krill, both at a concentration of 5 mg/L, were subjected to treatment under subcritical water conditions using a flow-type reactor to compare the degradation of free astaxanthin and astaxanthin fatty acid esters.
View Article and Find Full Text PDFFreezing and thawing of oil-in-water (O/W) emulsion-type foods bring about oil-water separation and deterioration; hence, the effects of freezing and thawing conditions on the destabilization of O/W emulsions were examined. The freezing rate and thawing temperature hardly affected the stability of the O/W emulsion. O/W emulsions having different oil fractions were stored at temperatures ranging from -30 to -20 °C and then thawed.
View Article and Find Full Text PDFDispersion and oxidative stability of O/W emulsions and oxidation of microencapsulated oil.
Biosci Biotechnol Biochem
April 2017
Oil-in-water (O/W) emulsions are among the dispersion systems commonly used in food, and these emulsions are in thermodynamically unstable or metastable states. In this paper, various methods for preparing O/W emulsions are outlined. Since the commodity value of food is impaired by the destabilization of O/W emulsions, experimental and theoretical approaches to assess the stability of O/W emulsions are overviewed, and factors affecting the dispersion stability of emulsions are discussed based on the DLVO theory and the concept of the stability factor.
View Article and Find Full Text PDFThe effect of the size of oil droplets on the oxidative stability of flaxseed oil in spray-dried powders was investigated. Maltodextrin with a dextrose equivalent of 25 was used as a wall material, and sodium caseinate and transglutaminase-polymerized sodium caseinate were used as emulsifiers. The oxidative stability of flaxseed oil encapsulated in the spray-dried powders was evaluated using lipid oxidation and conductometric determination tests at 105 °C.
View Article and Find Full Text PDFEncapsulating fish oil by spray drying with an adequate wall material was investigated to determine if stable powders containing emulsified fish-oil-droplets can be formed. In particular, the dextrose equivalent (DE) of maltodextrin (MD) affects the powder structure, surface-oil ratio, and oxidative stability of fish oil. The carrier solution was prepared using MD with different DEs (DE = 11, 19, and 25) and sodium caseinate as the wall material and the emulsifier, respectively.
View Article and Find Full Text PDFDistribution of saccharides and salts on amphoteric ion-exchange resin.
Biosci Biotechnol Biochem
April 2017
An amphoteric ion-exchange resin hardly shrank in 550 and 300 g/L glucose and sodium chloride solutions, respectively; however, the bed packed with a cation-exchange resin shrank considerably. From the distribution coefficients of some saccharides, the swelling pressure of the amphoteric ion-exchange resin was estimated to be 2.0 MPa at 25 °C.
View Article and Find Full Text PDFDegradation kinetics of passion fruit pectin in subcritical water.
Biosci Biotechnol Biochem
April 2017
The degradation of passion fruit pectin by subcritical water treatment in a continuous flow-type reactor was investigated in the temperature range of 80-160 °C at a constant pressure of 5 MPa. Changes in the degree of polymerization and reducing end formation were monitored and modeled by applying the Emsley equation and zeroth-order kinetics, respectively. The results showed that both the pectin degradation rate constant and the change in the amount of reducing end were enhanced by temperature, and that the temperature dependence of these parameters obeyed the Arrhenius relationship.
View Article and Find Full Text PDFDetection of cracks in dried spaghetti using transmission images.
Biosci Biotechnol Biochem
April 2017
Cracks are formed during the drying process of spaghetti production, which reduces its commercial value and quality; hence, it is very important to detect the cracks during the manufacturing process of dried spaghetti. However, the presence of mottles, originating from wheat bran, hinders automatic identification of cracks. In this study, we developed a simple method to detect the cracks induced in spaghetti using a digital camera.
View Article and Find Full Text PDFCharacterization, sensory evaluation, and astaxanthin stability of isada krill under various subcritical water conditions were investigated to optimize the quality of krill extract and residue for producing food seasoning. Raw krill (82% wet basis moisture content) without additional water was treated in a pressure-resistant vessel for 10 min at a temperature range of 100-240 °C. The yield of water-soluble protein was maximized by treatment at 200 °C and decreased with treatment at higher temperatures.
View Article and Find Full Text PDFDecomposition Kinetics of Glucose and Fructose in Subcritical Water Containing Sodium Chloride.
J Appl Glycosci (1999)
November 2016
The kinetics of the decomposition and isomerization of glucose and fructose in pure water and water containing sodium chloride (1-20 % w/w) under subcritical conditions at 180-220 °C was investigated. The addition of sodium chloride in subcritical water accelerated the decrease of glucose, and the rate was expressed by the Weibull equation. Although the isomerization of glucose to fructose was observed in parallel with decomposition, the yield of fructose was lower at higher sodium chloride concentrations.
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