Certain qualitative properties of Citrus depressa juice extracted by belt-press, centrifugal, and screw-press extractors were investigated to evaluate the methods for extracting Citrus depressa juice currently used in Japan. Among the three methods, juice yield was highest with screw-pressing. The migration rate of polymethoxyflavonoids (PMF) to the juice was also highest with screw-pressing. Screw-pressed juice had different physicochemical properties from the other two types of juices, and it was evaluated as being unsuitable for drinking following a sensory test. Citrus depressa juice processed by belt-press and centrifugal extractors had lower juice yield and a lower migration rate of PMF. Citrus depressa juice processed by centrifugal extractors was evaluated by a sensory test as being the best of the three types of juices for drinking. PMF and vitamin C found in Citrus depressa juice were largely retained during filtering, sterilizing, and bottling after being extracted with these three methods.
Initial freezing point and freezable water fraction, as the two parameters to determine the temperature dependence of fraction of frozen water, were measured systematically for solutions of glucose, its oligomers, dextrans, and potato starch. Initial freezing point was described by 2nd order polynomial of solute concentration. Freezable water fraction was described by 0.5th order function of solute concentration for glucose, maltose, and maltotriose or by linear function of solute concentration for dextran solutions and potato starch suspensions. Freezable water fraction increased with an increase in the molecular weight of solute. Temperature dependence of fraction of frozen water was different between solutions with low molecular and high molecular solutes reflecting the difference in their hydration states.
Visible and near infrared spectroscopy was investigated as a method for rapid analysis of the sugar compositions of raw ume juice. In total, 314 raw ume juice samples were collected over a long growth period and visible and near infrared transmittance spectra between 400 and 1850nm were acquired using a spectrophotometer with a quartz cuvette with 1-mm thickness. The partial least squares (PLS) calibration models for the total sugar content of ume fruit juice were developed using original spectra and pretreated spectra (normalization, first derivative, second derivative and multiplicative scatter correction) in five different wavelength ranges. The best models used the second derivative spectral data in the wavelength ranges of 1100-1850nm with the lowest standard error of prediction (0.133%). Moreover, good calibration models for sugar compositions (fructose, glucose, sorbitol, sucrose) of ume juice were obtained using the same second derivative spectral data in the wavelength range of 1100-1850nm, and gave relatively good predictions with high value of R2 and low value of SEP : fructose, 0.96 and 0.062% ; glucose, 0.94 and 0.068%, sucrose, 0.92 and 0.065%, sorbitol, 0.87 and 0.046, respectively. Results indicated that near infrared spectroscopy provided useful method to rapidly analyze the total sugar content and the sugar composition of raw Ume fruit juice.
A new ohmic thawing system was tested with a frozen saline surimi cube. The thawing rate and surimi gel strength in the ohmic thawing process were investigated, in comparison with conventional thawing technique. The electric mechanism for the ohmic thawing process was also discussed. Under the condition of the applied voltage of 20V and frequency of 60Hz, a homogeneous temperature distribution in the frozen surimi was obtained when the concentration of electrode solution was below 4.0%. The thawing rate increased linearly with the increasing concentration of electrode solution. The changes in thawing rate and temperature distribution with the concentration of electrode solution could be explained by an equivalent electric circuit. The ohmic thawing had a higher thawing rate and resulted in stronger gels than the conventional thawing. The present study indicates that the ohmic thawing system can be applied well in the thawing of frozen surimi.
Textures of cooked rice prepared from aged rice and improvements in cooked rice through removal of its external layer were investigated. Cooked rice prepared from aged rice became hard and stickiness/hardness (S/H) ratios were significantly lowered in comparison to that of new rice. The cooked rice prepared from aged rice with 7% of the external layer removed became soft and no significant differences existed between the S/H ratios of new rice and aged rice. The soaking solution of rice became starchy solution at the time of heating. The amount of the solid of starchy solution was significantly decreased in aged rice compared with new rice, and that of further polished and aged rice was increased. Therefore, we presumed that the starchy solution became a gelatinous paste layer of starch on the rice grain surface after cooking, and that the amount of the solid of starchy solution was related to the textural deterioration of aged rice and the textural improvement by partial removal of the external layer in aged rice. The RVA pasting properties of the flour in aged rice were also different from those of new rice. However, their changes were different from those for cooked rice texture.
This study was conducted to determine whether dietary psyllium (PSY) can protect against the estrogenic activity of Bisphenol A (BPA) in a rat uterotrophic bioassay. Fifteen immature female rats were fed a commercial diet (blank diet), a blank diet containing 0.1% BPA (control diet), or a blank diet with 0.1% BPA and 5% PSY (PSY diet) for 6 days. The uterine weight of the control group was significantly higher than of the blank group. The uterine weight and the uterine BPA levels of the PSY group were significantly lower than the control group. Serum BPA concentrations and liver BPA levels of the PSY group tended to decrease compared to the control group. However, BPA excretions in feces were significantly higher in the PSY group than in the control group (p<0.01). These observations indicate that dietary PSY feeding can protect against the estrogenic activity of BPA in rats.
While kiwi fruit seeds are ingested with sarcocarps, biological activities associated with these seeds have not been examined. We evaluated the effects of the extract of defatted kiwi fruit seeds (KSE) on inflammation and melanin production. In a mouse writhing model stimulated by acetic acid, KSE (100-400mg/kg) suppressed the increase in abdominal capillary permeability in a dose-dependent manner. KSE inhibited lipopolysaccharide-induced prostaglandin (PG) E2 production, but not nitric oxide (NO) production from RAW264 cells. Quercitrin and kaempferol 3-O-rhamnoside, flavonol glycosides isolated from KSE, suppressed PG E2 and NO production only at high concentrations (100μg/mL). Hence, contribution of these compounds to the inhibitory activity of KSE appeared to be low. KSE, quercitrin, and kaempferol 3-O-rhamnoside showed inhibitory effects on tyrosinase activity and melanin production in B16 melanoma cells. However, daily oral administration of KSE (200-800mg/kg) for 24 days did not affect melanin production induced by ultraviolet ray (UV)-B irradiation ; instead, it enhanced the disappearance of pigmentation in the guinea pig skin. Consequently, KSE was found to suppress acute inflammation and enhance melanin disappearance. Although flavonol glycosides suppressed melanin production in vitro, their involvement in anti-inflammatory activity and melanin disappearance of KSE was not clarified.
Sorption isotherms of lincheu mushroom (ganoderma lucidum), a medicinal herb were determined at three temperature levels of 30°C , 40°C and 50°C in the range of the relative humidity from 11% to 97% by using dynamic method. Ten two variable and five three variable isotherm models were selected to fit the observed data. Two variables models are good for the temperatures for which these models were derived while the three variable models are good for any temperature within the range for which it was derived. Among the two variable models the GAB equation was found to be the best to the experimental isotherm data of lincheu mushroom for the temperature levels of 30, 40 and 50°C and the temperature effect on the parameters was not consistent. Among the three variable models the Day and Nelson equation was found to be the best to the experimental isotherm data of lincheu mushroom for the temperature levels of 30, 40 and 50°C. The GAB model and Day and Nelson model were the most suitable models for estimating sorption isotherms of lincheu mushroom. The heats of sorption of water were determined from the equilibrium data using the Clausiaus-Clapeyron equation. The heat of sorption of lincheu mushroom decreases with an increase in moisture content and is found to an exponential function of moisture content. This equation can be used for computation of heat of sorption of lincheu mushroom.
The possibility of recovering of proanthocyanidin (PA) from the by-product of Turkish traditional product pekmez (molasses) industry, one of the agro industries, was investigated. In order to obtain optimum extraction conditions, the effects of different solvents and their aqueous forms were studied and the highest PA concentration was achieved as 31 (±0.68)g/L with acetone/water (30 : 70, v/v) solution. The correlations between phenolic contents, PA concentrations and antioxidant capacities were shown. Antioxidant capacities of extracts were determined and the comparison of them with synthetic and commercial antioxidants was performed. The antioxidant capacity of PA extract from grape seed of molasses pomace was 93 (±1.43) TEAC values, which was relatively high compared with those of the synthetic antioxidants. Silk fibroin was used as a novel adsorbent to recover the PA from the grape seed extracts. Effect of parameters such as, solid-liquid ratio, pH and initial concentration of PA on the recovery performance was investigated. All parameters were found statistically significant parameters (P<0.005) and the best adsorption conditions were found to be pH 5.5, initial concentration as 10g/ml and solid-liquid ratio as 0.1g/ml, which yielded the maximum percentage of adsorbed PA amount as 85.2%.
A low tannin sorghum cultivar (Tabat) was used in this study. Sorghum unlike wheat does not contain gluten. It is a potential cereal for people suffering from Celiac disease. For preparation of bakery foods mainly bread the elasticity conferred by gluten in wheat is substituted by the addition of guar gum and gum Arabic. Hence, the objectives of this work were : functional properties of sorghum flours treated with guar gum and/or gum Arabic with intention of manufacture of bakery products. Functional properties considered were protein solubility, least gelation concentration, bulk density, water and oil binding capacity, emulsifying activity, foaming capacity and Farinograph characteristics. Treated samples in general were lower than untreated sorghum except for the bulk density and foaming capacity. The results indicated that acceptable bakery products e.g. bread and pizza could be obtained using 1% (w/w) guar gum with 38% (w/w) gum Arabic and 0.5% (w/w) guar gum with 38% (w/w) gum Arabic, respectively.
Globin (Gb), a rich source of essential amino acids, and Gbs glycated with sugars (glucose, fructose and psicose) by the Maillard reaction were applied to breadmaking, and their effects on the rheological properties of dough and qualities of finished bread were studied. The dynamic modulus of dough was improved by the addition of NaCl to wheat flour, as expected. An improvement in dynamic modulus was also observed when Gb was added to wheat flour without the addition of NaCl. Parameters determined by Farinograph showed that the addition of Gb and glycated Gbs to wheat flour dramatically improved rheological properties of dough. In finished bread formulated with NaCl at the low concentration of 0.17% (w/w, based on flour weight), the addition of 1% (w/w) of Gb resulted in unfavorable textures (stiff and tough) while 1% (w/w) psicose-glycated Gb made bread 30% softer, 22% more elastic and 4.8% larger in specific volume than control bread (no additional protein). Thus, psicose-glycated Gb can be a useful additive for producing a low-sodium bread with favorable texture.
Influence of fat-replacers on process and age (up to 6 months at 5°C ) induced water soluble nitrogen generation in lowfat (5%, w/w) Cheddar cheese was investigated. Treatments with cellulose plus guar gum based Novagel NC200 (NOV), starch based Stellar (STEL), and protein based Dairy Lo (DL) and Simplesse (SIMP) were compared with lowfat (LFC) and fullfat (32%) controls. Nitrogen contents in aqueous extract were determined by Kjeldahl method. Process induced proteolysis followed the order DL>NOV>SIMP>STEL>LFC>FFC. Age related proteolysis, which generated hydrophobic peptides, was rapid in the first 3 months, and resulted in an increase of non-protein nitrogen compared to post-process content by 113, 50, 17 and 14%, respectively for LFC, STEL, FFC, and NOV. Protein based DL showed a reduction in this value by 22% and SIMP showed no change. The ultrastructure of the DL treated cheese matrix appeared closer to FFC compared to all other treatments and the LFC in that smaller (<3μ) globular occlusions, representing butter-fat droplets, were seen compared to the dominance of larger (>3μ) non-globular occlusions in the NOV and SIMP treatments. While the LFC showed signs of globular coalescence and enlargement, DL, and to a lesser extent STEL treatments showed markedly less. The possible reason for the treatment effect on the cheese matrix ultrastructure is discussed.
The effects of cooling rate and 0.1∼0.5% sodium chloride (NaCl) on the gelation of 0.8% agar, gellan gum and κ-carrageenan solutions were investigated based on the storage modulus and by differential scanning calorimetry (DSC). Each polysaccharide solution without NaCl had higher values of equilibrium storage modulus at a slow cooling rate than at a rapid cooling rate. However, the enthalpy calculated from the area surrounded by a DSC curve and the base line was not influenced by the cooling rate. The gelation temperature of each polysaccharide solution was elevated and the effect of NaCl addition on the storage modulus of gellan gum and κ-carrageenan was intensified by slowing the cooling rate. Each aggregated molecule core might grow independently at a rapid cooling rate and the formation of network structure of gellan gum and κ-carrageenan at a slow cooling rate might be affected by intermolecular repulsion.
Four kinds of soft wheat flours, Takaragasa gold, Furian, Tokutakaragasa and Aokoma (protein 9.06, 9.30, 9.69 and 10.17%, respectively), which were commercially used for sugar- and protein-rich Kasutera cake, were stored at room temperature (15-25°C ) for 2, 4, 6, 8, 10 and 12 months. A Kasutera cake baking test with these stored wheat flours showed that the volume (cm3) of Kasutera cake was gradually increased with elapse of storage period. These wheat flours were fractionated into water solubles, gluten, prime starch (A starch granule) and tailings (mixture of water insoluble proteins, polysaccharides, lipids and B starch granule) fractions using an acetic acid fractionation technique. A gradual increase of the interaction between prime starch and tailings fractions could be observed from the inclusion of the prime starch to the tailings fractions in each wheat flour with storage. It was found that the increase of volume of the Kasutera cake was highly related to the interaction between the prime starch and tailings fractions in the stored wheat flours. Mixograph profiles showed that the hydrophobicity of the wheat flour depended on the storage period. RVA (Rapid Visco Analyser) profiles of these stored wheat flours showed that the onset time became earlier and the peak viscosity increased, likely due to the hydrophobic interaction of flour components.
The goal of the study was to determine the effect of homogenization of lactic cultures at 30MPa on the development of proteolysis in Kashar cheese during ripening. The cultures Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cemoris, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus and Lactobacillus helveticus were used in the study. After propagation, the cultures were homogenized at 30MPa and 40°C for 5 cycles. Cow milk was used to make Kashar cheese in the study. The cheeses were ripened at 8±1°C for 90 days. Chemical analyses, determinations of water soluble nitrogen (WSN), trichloroacetic acid-soluble nitrogen (TCA-SN) and phosphotungsticacid-soluble nitrogen (PTA-SN) contents and electrophoresis of casein bands were done on days 3, 30, 60 and 90. The results indicated that there was no significant effect of homogenization of the cultures on the chemical composition of Kashar cheeses (P>0.05). However, higher proteolysis values measured as WSN, TCA-SN, and PTA-SN were obtained from homogenized culture-added cheeses. Accumulation of PTA-SN content in the cheeses was significantly (P<0.05) affected by homogenization of the cultures. At the end of ripening, the homogenized culture-added cheeses had lower residual αs1- and β-caseins than the unhomogenized culture-added ones. The effect of homogenization of the cultures on the breakdown of αs1-casein was significant (P<0.05).
This study was carried out to evaluate the microbiological condition of the frozen shrimps found in the local markets and departmental chain shops of Dhaka city. Pathogenic bacterial load were found greater in the samples of departmental shops rather than that of local markets. The highest Aerobic Plate Count (APC) found in the samples of departmental shops and local markets were 8.74log10CFU/g (sample No. 14) and 8.30log10CFU/g (sample No. 8), respectively. However, the lowest APC found in the samples of departmental shops and local markets were 5.73log10CFU/g (sample No. 5) and 6.44log10CFU/g (sample No. 12), respectively. Presence of Vibrio spp. was confirmed in 8 samples (5 from departmental shops and 3 from local markets). It was confirmed that 8 samples contained Shigella spp and 11 samples had Salmonella spp. Antibiotic sensitivity pattern of the indicator and pathogenic isolates was determined and nearly all of them were resistant to penicillin and bacitracin. Most of the isolates were sensitive against tetracycline, kanamycin and chloramphenicol. It was observed from the study that the samples collected from local markets and departmental shops were heavily contaminated and are of special concern for human consumption.
Four phenolic compounds were isolated from Japanese butterbur (Petasites japonicus) by preparative RP-HPLC technique, and were identified as chlorogenic acid (CGA), fukinolic acid (FA), 3,5-dicaffeoyl quinic acid, and 3,4,5-tricaffeoyl quinic acid. Since the antioxidant activity of FA among these four compounds has not been reported in detail, we investigated the scavenging activity of FA against several active oxygens and radicals, compared with CGA, gallic acid (GA) and epigallocatechin gallate (EGCG), using ESR spectroscopy. The order of potency of scavenging superoxide anion, nitric oxide (NO) and DPPH was EGCG>FA>CGA. The order of potency of scavenging hydroxyl radical was EGCG>FA>GA. FA inhibited the lipopolysaccharide-stimulated NO production and inducible NO synthase protein and mRNA expression by mouse macrophage-like cells Raw 264.7 more potently than CGA. The present study suggests the usefulness of FA as an antioxidant.
The effects of salt and mustard on egg yolk protein hydrolysis in mayonnaise during preservation were investigated. Both the amount of liberated tyrosine and changes in the band around 200kDa on SDS-PAGE decreased with increasing concentration of salt during mayonnaise preservation. Egg yolk aspartic proteinase activity was activated at 1.0 to 3.0% (w/v) NaCl when a synthetic fluorogenic substrate was employed as a substrate. Proteinase activity was confirmed in the mustard water-soluble extract, with maximal activity at pH 4.5. The amount of tyrosine liberated during mayonnaise preservation increased with addition of mustard powder. The hydrolysis of egg yolk protein in the 0.8% (w/w) mustard sample was restricted by adding salt at 2% (w/w), but tyrosine liberated from samples preserved at 5°C for 5wk and at 20°C for 5d were to approximately 45% and 39% that of the non-salt-containing sample, respectively.
Wasabi (Wasabia japonica Matsum.) is a Japanese traditional spice. Many kinds of processed foods that include wasabi as an ingredient have been developed and produced. Here, we report on the detection of the myrosinase genes of wasabi from products containing wasabi. Because wasabi had multiple copies of myrosinase genes that closely resembled each other, primers were designed so that the gene family could be amplified. Polymerase chain reaction with the primers indicated that fragments of the myrosinase genes were amplified from DNA samples of all wasabi cultivars tested, but no bands were found when DNA of other species, such as horseradish, radish, spinach, and pea, were tested. In addition, the system could detect wasabi myrosinase genes from food products that included wasabi. These results suggest that this technique is applicable for the specific detection of wasabi in a variety of products.
The preventive effect of the development of the late allergic eosinophilic rhinitis (LAER), a T helper (Th)2 type immune response, in BALB/c mice by kurozu moromi powder (kmp) was examined. Mice were pre-treated with or without (control) kmp intragastrically for 30 days (50mg/kg/day) and then LAER was induced by ovalbumin. Compared to the control group, kmp treatment resulted in reduction of the number of eosinophils, but not lymphocytes, in the blood. The kmp treatment significantly decreased concentration of interleukin (IL)-4, the Th2 cytokine, compared to the control in nasal cavity fluid (NF). However, no difference or increase in concentration of interferon-γ, a Th1 cytokine, in NF was observed in the two groups. The control group showed slight to moderate rhinitis, such as hyperplasia of respiratory epithelium and goblet cells with prominent mucous secretion and infiltration of eosinophils and lymphocytes in nasal mucosa. These changes were significantly reduced in mice treated with the kmp. The inhibitory effect of the kmp on the development of LAER may be due to decreased local Th2 cell activity promoting eosinophil infiltration, which is separate from the mutual Th1/Th2 inhibitory effect. In addition, the present study suggests that the kmp may be a useful food for prevention of the development of LAER in humans.
The effect of heat treatment of film-forming solutions on the properties of edible surimi films was investigated. The film-forming solutions prepared at pH 3 from frozen Alaska pollack surimi were heated to 45, 70 or 100°C to promote unfolding of surimi protein molecules. As a result, solubility, surface hydrophobicity, and reactive SH group of surimi proteins increased. After 45°C -treatment, the mechanical properties, film solubility, and protein solubility of surimi films were not affected and myosin heavy chain (MHC) of surimi proteins was degraded by endogenous acid proteinases. Conversely, at higher heating temperatures (70°C, 100°C), degradation of MHC was effectively inhibited and mechanical properties were improved, while the film solubility and protein solubility of surimi films decreased. It is revealed that the prevention of MHC degradation by heat treatment could improve mechanical properties of surimi films. The optimum condition was found to be heating the film-forming solutions (pH 3) at 70°C for 20min.
The present study clarified the changes of lipid components, which are considered to be most involved in physiological properties, stability against oxidation, and flavor formation during peanut tofu production. The chemical characteristics of lipids were nondrying oil and within the range of those in peanut oil. POV and AV level was high in roasted peanut, suggesting that peanuts were susceptible to thermal oxidation during the roasting process. Lipid composition was 97.8-98.6% NL, 0.73-1.01% GL and 0.6-1.2% PL. In NL and PL, triacylglycerol and phospholipids decomposition occurred, decreasing levels to 90.8%, 80.7% in dried peanut tofu and 83.1%, 41.6% in roasted peanut tofu, respectively. Among the main fatty acid components in TL, NL, and PL, C18 : 1 was the greatest, followed by C18 : 2 and C16 : 0. Long-chain fatty acids, such as C22 : 0 and C24 : 0, were also detected. Among the unsaponifable matter, α-Toc, which is physiologically active, and γ-Toc, which is highly antioxidative, were detected. The level of β-sitosterol was highest at approximately 75% of 4-Desmethylsterol.
Polyphenols, a large group of natural antioxidants, are a versatile group of phytochemicals beneficial for disease prevention. In this study, we comprehensively analyzed polyphenols, catechins, procyanidins, simple polyphenols, anthocyanins and flavonoids, in fruits consumed in Japan by high performance liquid chromatography with photo-diode array and mass spectrometric detection to complete the database of food components.
Soybean saponin has been reported to change the nature of proteins. Thus, crude saponin fraction or isolated soyasaponin I was added to Bowman-Birk inhibitor (BBI) from soybeans to evaluate the effect on its trypsin-inhibiting activity. The soybean saponin and soyasaponin I used in the experiment had little effect on tryptic activity. The trypsin-inhibiting activity of the mixture consisting of BBI and saponin was gradually enhanced by increasing saponin fraction or isolated soyasaponin I. Circular dichroism (CD) spectra of BBI were proportionally changed with the increase in soyasaponin I to imply change in structure of BBI. These results suggested that the conformational change by saponin caused enhancement of the trypsin-inhibiting activity of BBI.
The role of high molecular weight compounds in the radical-scavenging activity of horse mackerel muscle was evaluated. After denaturation by boiling or by adding TCA solution, 30% of the total activity remained in the water extract. Fractions containing high molecular weight compounds showed both 1,1-diphenyl-2-picrylhydrazyl and peroxy radical-scavenging activity. These results indicate that water-soluble protein in fish muscle is responsible for the radical-scavenging activity.
This paper describes the features of new characteristic rice cultivars developed in the Hokuriku region, especially Hokuriku 166 (floury mutant rice) and Hokuriku 169 (sugary mutant rice), in comparison with Koshihikari. Using Hokuriku 166, it is easy to make fine rice flour because the starch granules for this cultivar are globular and small. Therefore, this cultivar is popular because it is easy to handle. Hokuriku 169 has a high proportion of bran and high γ-aminobutyric acid (GABA) content. The fineness of Hokuriku 166 rice flour and the component parts of Hokuriku 169 are promising as raw material for processing.