小林 史幸

Abstract: The characteristics of bread prepared with coconut oil were investigated to determine whether it can be used as an alternative to butter and shortening. Loaf height of the bread increased by adding butter and shortening water content of bread containing oils and fats was lower than that without oils and fats, and baking loss increased with decreasing water content. The addition of oils and fats influenced the baking color of bread and hindered the hardening of bread samples over time. Moreover, the addition and type of oils and fats influenced the crust density of bread samples and dough expansion. Furthermore, numerous fine bubbles were present in bread samples without oils and fats, whereas the size and number of bubbles increased and decreased in bread samples containing oils and fats, respectively. The band concentrations of insoluble proteins at approximately 39, 41, and 48 kDa in freeze-dried bread samples without oils and fats were significantly lower than those containing oils and fats. Thirty volatile compounds were detected in all bread samples tested, and the number was high in the following order: bread samples with butter, shortening, and coconut oil, and without oils and fats. However, sensory evaluation showed no significant differences among all bread samples tested. Therefore, it was suggested that bread containing coconut oil had the same characteristics as that containing butter and shortening. Practical Application: Butter and shortening are usually used in bread making, although bread prepared with coconut oil can possess the same characteristics as that containing them. Therefore, this study evaluated the characteristics of bread prepared with coconut oil and revealed that use of coconut oil enabled a vegan bread with reduced environmental impact because coconut oil is a vegetable-derived oil that does not require the cutting of tropical rainforests.

Background and objectivesThis study investigated the use of coconut oil as an alternative to butter and shortening in bread making by analyzing the dough characteristics for feasibility. FindingsIn the fermentation test, the pH of the dough containing oils and fats was reduced to <5.1 of the threshold, which deteriorated the extensibility. The pH further decreased with an increased CO2 emission rate from the dough. In the compression test, the stress of the dough containing oils and fats was lower than that without it. However, the stress on gluten-containing oils and fats was significantly high and differed based on the type of oils and fats. A large network structure of gluten with distributed starch granules was observed using scanning electron microscopy in the dough containing oils and fats. Numerous starch granules were uniformly distributed in the spaces of the gluten network structure, making the dough softer. ConclusionsIt was recognized that the characteristics of the dough containing coconut oil were similar to that of the dough containing butter or shortening. Significance and noveltyThis study suggested that coconut oil can be used as an alternative oil and fat to butter or shortening for bread making.

For the purpose of clarifying the relationship between pasteurization and inactivation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in Saccharomyces pastorianus cells induced by pressurized carbon dioxide microbubbles (CO2MB) treatment, a storage test of S. pastorianus cells after CO2MB treatment was conducted to ascertain their recovery, and the treatment condition in the inactivation of GAPDH in S. pastorianus cells by CO2MB was investigated. Each population of S. pastorianus for 48, 96, and 144 h at 25°C was decreased significantly by CO2MB treatment at 35°C for 3 min (MB35-3 and MB35-5) or at 40°C and 45°C for 1 and 3 min (MB40-1, MB40-3, and MB45-1). In the storage test, recovery of treated cells was not observed after storage for 144 h at 25°C. The denaturation of GAPDH in the S. pastorianus cells caused by the same treatment as the storage test was detected by using sodium dodecyl sulphate polyacrylamide gel electrophoresis. While the activities at MB35-1, MB35-3, and MB40-1 were significantly higher than those at non-treatment, and those at MB35-5, MB40-3, and MB45-1 were lower. Therefore, GAPDH denaturation, but not the activity, was associated with the inactivation of S. pastorianus cells.

This study examined the changes in petal colour, antioxidant activity, and volatile components of miniature roses, one of the most popular edible flowers in Japan, when stored under different conditions. In total, six storage treatments were examined: 5°C and 75% relative humidity (RH) for 3 d (75%-3D plot); 5°C and 75% RH for 6 d (75%-6D plot); 5°C and 96% RH for 3 d (96%-3D plot); 5°C and 96% RH for 6 d (96%-6D plot); -25°C for 3 d (F-3D plot); and -25°C for 6 d (F-6D plot). As a control, a measurement was conducted on day 0 without storage (0D plot). There were no significant differences in flower width, fresh weight, and total polyphenol concentrations among the storage treatments. DPPH radical scavenging activity decreased during storage, especially during freezing storage, but was higher in the 75%-3D plot than that in the other storage conditions. A colour difference was found between the cold and freezing storage treatments because of colour changes after freezing and thawing. The sweet aroma decreased during storage, and a bad smell was detected in the freezing treatment. Freezing storage was thus unsuitable for storing edible roses because it degraded colour, decreased antioxidant concentrations, and increased a bad smell. The flower colour measured using a chromameter and DPPH radical scavenging activity in the 75%-3D plot were not significantly different from those in the 0D plot. Further, the total volatile component contents in all 6D plots were lower than those in all the 3D plots during cold storage. Therefore, these findings indicate that edible roses should be stored under refrigeration at 75% RH and used within approximately three days after purchase. This information can be helpful to food, cosmetic, and pharmaceutical industries that require preservation of edible flowers.

Edible flowers represent rich sources of nutritional and phytochemical compounds. Violas (Viola × wittrockiana) have been confirmed to be non-toxic as food products. Based on the wide variety of flower colours, major differences may exist in antioxidant concentrations among flowers of different colours. This study examined the differences in concentrations of antioxidant components in viola flowers of eight different colours: white, red, dark red, orange, yellow, light blue, light purple, and dark purple. Flower fresh weight, petal length, petal colour (measured using a chroma metre), ascorbic acid concentration, total anthocyanin concentration, total polyphenol concentration, and DPPH radical-scavenging activity were analysed. The violas used in this study had a wide range of colours, with different lightness and chroma values. Ascorbic acid, total anthocyanin, and total polyphenol concentrations were higher in red, dark red, and dark purple flowers. In contrast, these concentrations were lower in white and light-coloured flowers. The DPPH radical-scavenging activity was also lower in white and light-coloured flowers. Therefore, red, dark red, and dark purple flowers rather than white and light-coloured flowers of violas represent rich sources of antioxidant components and their consumption may provide various health benefits.

To clarify the relationship between irreversible inactivation and intracellular protein denaturation of Saccharomyces pastorianus by low-pressure carbon dioxide microbubbles (CO2MB) treatment, a storage test of S. pastorianus cells treated with CO2MB was performed, and the effect on the intracellular protein was investigated. In the storage test, the S. pastorianus population, which decreased below the detection limit by CO2MB treatment at a temperature of 45 and 50 degrees C (MB45 and MB50), and thermal treatment at a temperature of 80 degrees C (T80), remained undetectable during storage for 3 weeks at 25 degrees C. However, 4.1 and 1.3-logs of the S. pastorianus populations, which survived after CO2MB treatment at temperatures of 35 and 40 degrees C (MB35 and MB40), increased gradually during storage for 3 weeks at 25 degrees C. Insolubilization of intracellular proteins in S. pastorianus increased with increasing the temperature of CO2MB treatment. Activity of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) identified as one of the insolubilized proteins increased at MB35 and MB40 than non-treatment but disappeared at MB45 and MB50, and T80. Therefore, it was revealed that S. pastorianus cells inactivated below the detection level by CO2MB treatment did not regrow and that the denaturation of intracellular proteins of S. pastorianus was caused by CO2MB and thermal treatments. Furthermore, it was suggested that denaturation of intracellular vital enzymes was an important factor for achieving irreversible inactivation of S. pastorianus by CO2MB and thermal treatments.

To clarify the lethal injury related to the inactivation of Saccharomyces pastorianus cells by low-pressure carbon dioxide microbubble (CO2MB) treatment, surviving number, leakage of nucleic acids and proteins, fluorescence polarisation (FP) of the cell membrane, activity of alkaline phosphatase (AP), intracellular pH (pHin), mitochondrial membrane potential (MMP), cell surface hydrophobicity (CSH) and oxidative stress of S. pastorianus treated with CO2MB at various temperatures were measured. The number of surviving S. pastorianus cells decreased below the detection limit after CO2MB treatment at temperatures of 40, 45 and 50 ℃, inducing a 2-log reduction at 35 ℃. The S. pastorianus cells treated with CO2MB at temperatures above 40 ℃ showed an increase in FP and leakage of nucleic acids and proteins. The AP in S. pastorianus cells treated with CO2MB at a temperature of 35 ℃ was also activated but inactivated at temperatures above 40 ℃. Furthermore, the decrease in pHin and MMP and the increase in CSH of S. pastorianus were caused by CO2MB treatment at temperatures above 35 ℃. Oxidative stress in S. pastorianus cells was also increased by CO2MB treatment without warming but decreased at temperatures above 35 ℃. Our results lead us to infer that the type of cell injury in S. pastorianus induced by CO2MB treatment differed from that caused by the treatment temperature and that the lethal injury was enzyme inactivation.

Effect of electrolyzed water (EW) produced from sodium chloride solution in a single vessel and carbon dioxide microbubbles (CO2MB) on decomposition of diazinon and its oxidized product, diazoxon, was investigated. Furthermore, these removal by the EW with CO2MB from broccoli-attached diazinon was examined. Diazinon was oxidized to diazoxon by EW, and the oxidative effect increased with increasing EW concentration from 0.1 to 0.6 mol L-1 or electrolyzing time from 1 to 10 min. However, EW concentration more than 0.2 mol L-1 was required to reduce diazoxon. The effect of EW on the decomposition of diazoxon increased with increasing EW concentration, electrolyzing time or reaction time from 10 to 60 min but decreased by generating CO2MB. Furthermore, diazinon concentration in broccoli was significantly decreased by treatment with deionized water or EW for 10 min, and the removal effect was continued by generating CO2MB in EW until 60 min. The diazoxon concentration in broccoli treated by EW decreased after increased up to 30 min, and the removal effect was increased by generating CO2MB. Also, the pH and available chlorine concentration (ACC) of the EW increased with increasing EW concentration or electrolyzing time but decreased and almost unchanged by generating CO2MB, respectively. Therefore, it was revealed that EW had a decomposition effect on diazinon and diazoxon and that CO2MB promoted the effect of EW on the removal of these pesticides in broccoli. Additionally, the decomposition effect of EW on diazinon and diazoxon was suggested to be influenced by high pH and ACC. Practical Application The EW produced from NaCl solution in a single vessel is a safer technique easy to be used than that from HCl. In addition, CO2MB has no harmful effects on the human body. This study demonstrated that the EW was effective for decomposing diazinon, an organophosphorus insecticide, and diazoxon, its oxidized product, and that the removal of these pesticides in broccoli by the EW could be more effectively achieved by generating CO2MB. Therefore, the use of EW with CO2MB can be expected to remove pesticides from fruits and vegetables at food factory.

Dissolved carbon dioxide (dCO2) stripping from a model solution containing sake flavor by feeding gaseous nitrogen (N2) using a microbubble (MB) generator was investigated. The effect of dCO2 stripping by N2MB increased significantly with increasing flow rate of gaseous N2 from 100 to 200 mL/min. dCO2 stripping from 3,000 mL of the model solution was achieved by feeding N2MB at a flow rate of 200 mL/min for 4 min. Volatile components from model solution containing sake flavor were hardly reduced even after feeding N2MB at a flow rate of 200 mL/min for 15 min by cooling to below 10 °C. On the other hand, non-microbubbled gaseous N2 at a flow rate of 200 mL/min was not very effective in stripping dCO2. Therefore, the use of N2MB with cooling to below 10 °C was effective in stripping dCO2 while maintaining the volatile components in model solution containing sake flavor.

The effect of seasonings on the quality retention of dried mackerel (Scomber scombrus Linnaeus) was investigated by analyzing the components of the seasonings and prepared dried mackerel. The pH, water content, salt concentration, and inosinic acid content of dried mackerel were influenced by the water content of seasoning liquid. The free amino acid content of dried mackerel depended on the seasoning liquid. The DPPH radical-scavenging activity of mirin seasoning liquid was significantly higher than that of salt and chorizo, and that of black seven spices (shichimi) and chorizo seasoning powders was extremely high. The content of some aldehydes, alkenes, and alkane of dried mackerel flavored with mirin, shichimi, and chorizo was significantly lower than that flavored with salt. Hexanal concentration further decreased in dried mackerel flavored with shichimi and chorizo. Therefore, the use of shichimi and chorizo as seasoning powders was effective for maintaining the quality of dried mackerel.Practical applications The production and consumption of dried fish have decreased yearly in Japan. Recently, two types of seasonings flavored with shichimi and chorizo have been, therefore, developed for preparing dried mackerel. These seasonings consisted of liquid and powder. This is the first attempt to use seasoning powders in the production of dried mackerel. This study demonstrated that the generation of fishy volatile components from dried mackerel was inhibited by the shichimi and chorizo seasoning powders.

<tt>本研究では，ブランチング処理の有無が冷凍枝豆の香気に与える影響について調査した．ブランチング処理をした枝豆試料と非ブランチング試料を真空包装後に急速凍結させ，同等な食感を与える調理条件の下で茹で加熱し，官能評価とにおい嗅ぎ</tt>GC-MS<tt>（</tt>GC-MS/O<tt>）による香気分析を行った．官能評価の結果より，喫食時に鼻から抜ける香りでは有意差が認められなかったが，喫食直前の莢の香りでは，非ブランチング冷解凍試料の方が有意に良好であった．また，</tt>GC-MS/O <tt>の分析結果より，非ブランチング冷解凍試料ではグリーン様香気表現がより多く検出された．したがって，ブランチング処理の有無において枝豆香気に影響を与えるのは莢であることが示唆された．</tt>

Although manufacturing conditions affect the texture of processed cheese, the effects of manufacturing conditions on flavour expression, and the mechanisms for these effects are unknown. This study investigated the effects of mixing temperature on the flavour expression of processed cream cheese and aimed to determine whether the content of aroma compounds in the matrix, the texture, and hydrophobic interactions between aroma compounds and the matrix contribute to flavour expression. Four model cheeses with mixing temperatures of 30 degrees C, 60 degrees C, 75 degrees C, and 88 degrees C were prepared. Sensory analysis, volatile aroma compound evaluations using HS-SPME and SAFE-GC/MS, texture analysis, microstructure observation, and hydrophobicity evaluation were conducted. The result showed that the decrease of scores for perceptions of "Yoghurt aroma", "Acidity", and "Acetic aroma" with increasing mixing temperature was due to the generation of aroma compounds. The decrease in scores for "Overall flavour intensity" was due to the product's hardened texture. (C) 2020 Elsevier Ltd. All rights reserved.

© 2019, Association of Food Scientists & Technologists (India). Temperature-dependency on cell membrane injury and inactivation of Saccharomyces pastorianus by low-pressure carbon dioxide microbubbles (MBCO2) was investigated. The number of surviving S. pastorianus cells after MBCO2 treatment detected with yeast and mould agar (YMA, an optimum agar) was higher than that with YMA adding 2.5 g/L sodium chloride and yeast nitrogen base agar (a minimum agar). However, the decrease of the surviving number by thermal treatment was not changed among above agars used. The fluorescence polarization (FP), which indicated the phase transition of the membrane of S. pastorianus cells treated with MBCO2 increased with increasing temperature. The activity of the alkaline phosphatase (AP), a periplasmic enzyme, in S. pastorianus cells after MBCO2 and thermal treatments increased with the FP but was reduced by further increasing temperature. The FP and AP activities after MBCO2 treatment increased at a temperature lower than the temperature of the thermal treatment. In addition, intracellular pH of S. pastorianus decreased by the MBCO2 treatment at lower temperature with increasing pressure. Therefore, it was revealed that phase transition of the cell membrane and inactivation of S. pastorianus was caused by MBCO2 treatment at lower temperature than thermal treatment and that the effect was induced by the dissolved CO2 and increased with increasing pressure.

© 2019 Elsevier Ltd The efficiency of low-pressure carbon dioxide microbubbles (CO2MB) to inactivate α-amylase was analysed kinetically, and structural alteration of α-amylase by CO2MB was investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescence analysis of tryptophan (Trp) residues. Activity and Trp fluorescence intensity of α-amylase treated by CO2MB decreased with increasing temperature, pressure and exposure time, and lowering the initial buffer pH, respectively. In the kinetic analysis, it was confirmed that the decreased temperature-dependency and increased activation energy associated with the inactivation of α-amylase by CO2MB were induced by pressurizing the mixing vessel and that the decreased pressure-dependency and increased activation volume concomitant to the inactivation of α-amylase by CO2MB was induced by increasing the temperature in the heating coil. In SDS-PAGE, CO2MB was suggested to induce the structural alteration of α-amylase because the band density decreased after CO2MB treatment, although this phenomenon was not related to the inactivation efficiency. However, Trp fluorescence analysis showed that the alteration of the tertiary structure of α-amylase by CO2MB was related to the inactivation efficiency. Therefore, CO2MB was more effective than thermal treatment in inactivating α-amylase, and the inactivation efficiency was suggested to be related to the alteration of the enzyme's tertiary structure.

© 2019 Elsevier Ltd Pressurized carbon dioxide (CO 2 ) is a promising technique for inactivating enzymes and microorganisms in food, although there are no discussion about handling of residual CO 2 . Therefore, the effect of cooling temperature and nitrogen (N 2 ) gas flow on removing dissolved carbon dioxide (CO 2 ) were investigated as means of retaining the flavour components in a model solution containing sake flavour treated with low-pressure CO 2 microbubbles (MBCO 2 ). The residual ratios of ethyl acetate, isobutyl alcohol and isoamyl alcohol in the model solution were largely uninfluenced by adding MBCO 2 to the mixing vessel. However, isoamyl acetate, isobutyl acetate and ethyl caproate were significantly lost by heating to 65 °C, although these component loss could be prevented by cooling to below 20, 10 and 5 °C, respectively. Furthermore, even if dissolved CO 2 in model solution treated with MBCO 2 was removed by N 2 gas flow, the flavour components levels were comparable to those before degassing. These results suggested that N 2 gas flow with a Y-branch after cooling below 5 °C was a promising method for removing dissolved CO 2 .

© 2017, © 2017 The Journal of Horticultural Science & Biotechnology Trust. The use of microbubbles (MB) can improve the oxygen supply to plants grown under the deep flow technique of hydroponic culture. In a previous study, we compared the growth of komatsuna (Brassica rapa L. perviridis, Japanese mustard spinach) plants grown under hydroponic culture with MB generated by the pressurisation (P) method and the gas-water circulation (G) method. Plant growth was significantly lower in the presence of the P-MB than the G-MB. In this study, we aimed to identify the factor(s) responsible for the poor growth of komatsuna plants in the presence of P-MB. At three weeks after planting, the growth of the P-MB plants was less than the growth of G-MP plants and controls, regardless of dissolved oxygen concentrations. Analysis of the root tips by transmission electron microscopy showed plasmolysis of the P-MB root tip cells but not of the G-MB and control root tips. Our results suggest that the growth inhibition of plants grown in the presence of P-MB is due to inhibition of water and nutrition absorption from root tip cells due to this plasmolysis. This is likely due to oxidisation of root tip cells by hydroxyl radicals generated by many fine MB and/or osmotic stresses caused by the MB.

© The Korean Society of Plant Pathology. To investigate the difference in the disinfectant efficiency of ozone microbubbles (O3MB) and ozone millibub-bles (O3MMB), the morphological change of the treated Fusarium oxysporum f. sp. melonis spores was observed with scanning and transmission electron microscopies (SEM and TEM). The disinfectant efficiency of O3MB on F. oxysporum f. sp. melonis spores was greater than that of O3MMB. On observation with SEM, it was revealed that morphological change of F. oxysporum f. sp. melonis spores was caused by O3MB and O3MMB, and damage to the spore surfaces by O3MB occurred sooner than that by O3 MMB. On observation with TEM, it was furthermore confirmed that F. oxysporum f. sp. melonis spores treated with O3MB induced wavy deformation of cell membrane and the intracellular change different from that with O3MMB. Therefore, the greater disinfection efficiency of O3MB was suggested to be caused due to the function of the MB in addition to the oxidative power of O3.

© 2018 Elsevier B.V. To investigate the relationship between intracellular acidification and inactivation of Saccharomyces pastorianus by a two-stage system with pressurized carbon dioxide microbubbles (two-stage MBCO2), the survivors and intracellular pH (pHin) of S. pastorianus suspended in buffers at various pHs after the two-stage MBCO2 treatment were measured. The inactivation efficiency of two-stage MBCO2 on S. pastorianus increased with lowering the initial buffer pH, although the pHin of S. pastorianus in pH 3 buffer was decreased by heating to 45 °C, regardless of the use of MBCO2. Conversely, the number of surviving S. pastorianus cells in pH 4 and 5 buffers was decreased by the two-stage MBCO2 without the pHin-lowering. Furthermore, the inactivation efficiency of two-stage MBCO2 on S. pastorianus increased with increasing pressure in the mixing vessel, although the pHin-lowering was caused by heating to 45 °C for all of the pressures tested, regardless of the use of MBCO2. Therefore, intracellular acidification of S. pastorianus by two-stage MBCO2 was due to the cell penetration of extracellular H+ associated with the temperature increase, and the inactivation was suggested to be induced by the combined factors of increasing temperature, pHin- and pHex-lowering and high dissolved CO2 concentration.

© 2017 American Institute of Chemical Engineers The effect of ethanol on the inactivation of Saccharomyces pastorianus by a two-stage system with low-pressure carbon dioxide microbubbles (two-stage MBCO2) was investigated. Zero and >5 log reductions of S. pastorianus populations suspended in physiological saline (PS) containing 0% and 10% ethanol, respectively, occurred by the two-stage MBCO2 at a mixing vessel pressure of 1 MPa and a heating coil temperature of 40°C. Conversely, the detected number of surviving S. pastorianus cells in PS containing 5% ethanol was higher in yeast and mold agar (YMA, an optimum agar) than YMA with 2.5% sodium chloride, followed by yeast nitrogen base agar (YNBA, a minimum agar). The fluorescence polarization of S. pastorianus in PS containing 5% and 10% ethanol increased similarly with exposure time in the heating coil of two-stage MBCO2 and was correlated with the surviving cell number measured in YNBA. The intracellular pH (pHin) of S. pastorianus in PS containing 5% ethanol decreased linearly with exposure time in the heating coil of two-stage MBCO2. Also, the pHin-lowering of S. pastorianus in PS containing 10% ethanol was drastically caused by two-stage MBCO2 at 1 min exposure time in the heating coil but then stayed constant until 5 min, agreeing with the inactivation efficiency. Therefore, ethanol in S. pastorianus suspension was suggested to accelerate the cell membrane injury caused by two-stage MBCO2. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:282–286, 2018.

© 2016 Taylor & Francis Group, LLC. To provide the necessary oxygen for plant growth, the effectiveness of different generating methods of microbubbles (MB), a gas-water circulation type or a pressurization type (pressurization treatment), was investigated by comparing the growth characteristics and morphological observation of Brassica campestris L. var. Komatsuna Matsum. The plant growth in the pressurization treatment were significantly less than those in the circulation treatment at 3 weeks after planting. In plants grown in the pressurization treatment, epidermal cell abrasion and plasmolysis, indicators of cell death, were observed in root tip cells at 3 weeks after planting. The growth inhibition of plant in the pressurization treatment is suggested to be related to the oxidization of Fe in the nutrient solution under super-saturated dissolved oxygen conditions, the generation of hydroxyl radicals from MB, the oxidization of the root tip cell membrane, and osmotic stress to the roots.

© 2016 Elsevier Ltd The effects of intracellular acidification and damage of cellular membrane on the inactivation of Saccharomyces pastorianus by a two-stage method of low-pressure carbon dioxide microbubbles (two-stage MBCO2) were investigated. Intra/extra cellular pH (pHin and pHex) and propidium iodide (PI) uptake of S. pastorianus cells treated with the two-stage MBCO2 were measured by fluorescence analysis, and were compared with the inactivation efficiency. The pHex and pHin of S. pastorianus cells treated with only mixing vessel at 10 °C of two-stage MBCO2 was lower than those that were untreated. However, the surviving number and the pHin of S. pastorianus cells treated with the two-stage MBCO2 containing the mixing vessel at 1.0 MPa and the heating coil of 40 °C decreased concomitant with the exposure time, and the increase of the PI uptake ratio was confirmed. In addition, when the pressure of the mixing vessel was 1.0 MPa, the surviving number and the pHin of S. pastorianus cells significantly decreased, and the PI uptake ratio increased by increasing the temperature to 45 and 50 °C with the heating coil of the two-stage MBCO2. These results suggested that the inactivation of S. pastorianus by two-stage MBCO2 might be induced by the damage to the cellular membrane at 45 and 50 °C, and by the lowering of the pHin at 40 °C.

© 2016 Elsevier Ltd The inactivation efficiency of a two-stage system with low-pressure CO2 microbubbles (two-stage MBCO2) on Escherichia coli in physiological saline (PS) and commercial sterilized bovine milk (CBM), and aerobic bacteria in unpasteurized bovine milk (UBM) was investigated. Furthermore, protease-resistance of casein and the free amino acid contents in the treated milk were measured. The number of surviving E. coli cells in PS and CBM by the two-stage MBCO2 decreased with increasing pressure in a mixing vessel or increasing temperature in a heating coil. A 3-log reduction in aerobic bacteria in UBM was achieved by two-stage MBCO2 after 1 min with the heating coil at 45 and 50 °C. Casein in UBM treated with only mixing vessel of two-stage MBCO2 was easier to be decomposed by thermolysin, although the casein warmed with the heating coil was difficult to be decomposed by thermolysin and papain. In addition, most of the free amino acid contents in UBM were decreased by the two-stage MBCO2. Therefore, it was suggested that limited inactivation of aerobic bacteria, and change of protease-resistance of casein and free amino acid contents in UBM were induced by two-stage MBCO2.

© 2015 Elsevier Ltd. The effect of pressure in the mixing vessel on the inactivation of enzymes and hiochi bacteria and on the change in free amino acid content in unpasteurized sake (UPS) using a two-stage system of low-pressure carbon dioxide microbubbles (MBCO2) was investigated. At a pressure of 0 MPa in the mixing vessel, hiochi bacteria in UPS were completely inactivated by heating at 65 °C for 1 s with two-stage MBCO2; α-amylase, glucoamylase and acid carboxypeptidase were inactivated after heating for 5 s, although α-glucosidase activity remained at approximately 13% even after 20 s. However, the inactivation efficiency increased with increasing pressure in the mixing vessel. In addition, the contents of aspartic acid, glutamic acid, alanine and arginine, key free amino acids involved in producing the taste of sake, in UPS tended to decrease by two-stage MBCO2 at all tested conditions, although these were minimally affected by pressure in the mixing vessel and exposure time in the heating coil.

© 2015, Springer Science+Business Media New York. Yeast in unfiltered beer (UFB) was inactivated by a two-stage system that was additionally pressurised at an ambient temperature after carbon dioxide microbubbles (MB-CO2) were mixed with UFB at a low temperature and pressure (two-stage MB-CO2). The quality of the treated beer was compared with UFB and heat-treated beer (HTB). Five-log reductions could be achieved by two-stage MB-CO2 treatment with a heating coil at 50 °C for 5 min, while yeast in UFB was not completely inactivated by heat treatment at 80 °C for 5 min. In sensory evaluation of these beers, there were no significant differences on the score of flavour, although bitterness of two-stage MB-CO2-treated beer (MBB) was significantly low on the score of taste. In analysis of volatile compounds, dimethyl sulphide, dimethyl disulphide, β-myrcene and styrene in MBB were less than those in UFB and HTB. Glucose and maltose contents in MBB and UFB were almost the same, although those in HTB significantly decreased. Organic acids, except for acetic acid in MBB, were nearly identical with those in UFB and HTB. Most of the free amino acids in MBB were lower than those in UFB and HTB. Bitter units of beer increased in the order of MBB, HTB and UFB. These results suggested that two-stage MB-CO2 shows promise as a practical technique for inactivating yeast in UFB. The inactivation efficiency of two-stage MB-CO2 had less influence of materials in beer than that of heat treatment, and two-stage MB-CO2 has little negative impact on the beer quality.

© 2014 American Chemical Society. To determine optimal temperature of a two-stage system of low pressure carbon dioxide microbubbles (MB-CO2) for inactivating enzymes in unpasteurized sake (UPS), the effect of two-stage MB-CO2 containing a heating coil at various temperatures on the inactivation of the α-glucosidase in UPS was investigated, and the quality of the sake treated by two-stage MB-CO2 was estimated by sensory evaluation and component analysis. α-Glucosidase activity in the UPS was completely inactivated by two-stage MB-CO2 with a heating coil at 45 °C for 50 min, 55 °C for 5 min, 65 °C for 10 s (MB65), and 75 °C for 1 s, respectively. The quality of the MB65's sake was determined to be significantly excellent by the sensory evaluation. The reason was suggested to be due to relatively low contents of free amino acids, change in organic acid balance, and less damage to volatile compounds.

To clarify how Saccharomyces pastorianus cells were affected by a two-stage system that was heating and pressurizing after microbubbled carbon dioxide (MB-CO2) was mixed with the S.pastorianus suspension at low temperature and pressure (two-stage MB-CO2), S.pastorianus cells were observed by electronic microscopy and stained with propidium iodide (PI). Furthermore, the amounts of nucleic acid and protein leaked from treated S.pastorianus cells were determined and intracellular enzyme activities were measured. It was observed by scanning electric microscopy that wrinkles in S.pastorianus cells treated by two-stage MB-CO2 with a heating coil at 50°C (MB50) and heat treatments at 50°C and 80°C (H50 and H80) were more than those in untreated (NT) cells. Upon observation with transmission electron microscopy, it suggested that MB50 had a direct effect on the intracellular substrate, although little influence on the membrane, whereas H80 cells showed visible damage to cell membranes. However, it was recognized that PI intensity in MB50 cells was great than that in NT, H50 and H80 cells, and that the amount of nucleic acid and protein leaked from H80 cells was significantly higher than that of NT, MB50 and H50 cells. Furthermore, the enzyme inactivation efficiency in MB50 cells was the same as in H80 cells. These results estimate that inactivation of S.pastorianus by two-stage MB-CO2 was due to actions of MB-CO2 on the cell membrane and the intracellular substrate such as enzyme inactivation. © 2014 Elsevier Ltd.

To improve the inactivation efficiency of low pressure CO2 microbubbles (MB-CO2), we developed the MB-CO2 equipment from batch system to two-stage MB-CO2 system which was additionally pressurized at ambient temperature after MB-CO2 was mixed with a solution at lower temperature and pressure. Therefore, the effect of the two-stage MB-CO2 treatment for inactivating Saccharomyces cerevisiae was investigated. The two-stage MB-CO2 efficiency for the inactivation of S.cerevisiae dramatically increased by lowering the temperature and by increasing the pressure in the mixing vessel. Furthermore, its effectiveness significantly enhanced by increasing the temperature in the heating coil, although not by the pressure. As a result, using the two-stage MB-CO2 equipment was suggested as a new effective technique to inactivate S.cerevisiae. © 2013 Elsevier Ltd.

To establish the use of low-pressure carbon dioxide microbubbles (MB-CO2), developed as a food sterilizing method, as a practical technique for inactivating plant pathogens in hydroponic nutrient solution, Fusarium oxysporum f. sp. melonis and Pectobacterium carotovorum subsp. carotovorum were inactivated by MB-CO2. The inorganic components in the MB-CO2-treated hydroponic nutrient solution were also analyzed, and a growth test of leaf lettuces with the MB-CO2-treated hydroponic nutrient solution was performed. Five-log reductions in F. oxysporum f. sp. melonis spores and P. carotovorum subsp. carotovorum cells were achieved by MB-CO2 treatment performed at 15°C and 1.5MPa in the mixing vessel, and at 40°C or 45°C and 4.0MPa at the heating coil. No changes of the inorganic components in the MB-CO2-treated hydroponic nutrient solution were observed. Furthermore, CO2 dissolved in the hydroponic nutrient solution at high concentration by MB-CO2 treatment had little influence on the growth of leaf lettuces. MB-CO2 appears to be a promising new technique for inactivating plant pathogens in hydroponic nutrient solution. © 2013 Elsevier B.V.

Enzymes and Lactobacillus fructivorans in unpasteurized sake were inactivated by a two-stage method with low-pressure carbon dioxide microbubbles (two-stage MB-CO2), and the quality of the treated sake was evaluated by the measurement of volatile compounds and by sensory tests. No surviving L. fructivorans cells were detected, and α-amylase, glucoamylase and acid carboxypeptidase were completely inactivated after two-stage MB-CO2 treatment. However, the relative residual activities of α-glucosidase were 28%-36% and 1%-11% after the two-stage MB-CO2 treatment at 45 C and 50 C, respectively. The effectiveness increased with temperature and exposure time of the heating coil. Ethyl butyrate, isoamyl acetate, ethyl hexanoate and ethyl octanoate in unpasteurized sake were decreased to 28%-49% by two-stage MB-CO2, but these losses could be prevented by passing the two-stage MB-CO2-treated sake through a cooling coil. Furthermore, the sensory scores relating to the total aroma and total taste of the MB-CO 2-treated sake were higher than those of unpasteurized and heat-treated sakes. Industrial relevance: Sake is a traditional alcoholic beverage in Japan. Unpasteurized sake is generally subjected to heat treatment to prevent the growth of microorganisms and enzymatic activity, although heat treatment often causes undesirable changes in sake quality. Non-thermal processes using supercritical carbon dioxide (SC-CO2) have been widely studied as alternative processes. However, high pressure is necessary for effective pasteurization with SC-CO2 treatment and the equipment is prohibitively expensive. In this study, we proposed a pasteurization technique that uses low-pressure CO2 microbubbles as a novel technique, which could inactivate microorganisms and enzymes in unpasteurized sake at moderate temperature and lower pressure. © 2013 Elsevier Ltd. All rights reserved.

In this study, the effects of ozone microbubbles (OMCB) treatment at various water temperatures on the removal of residual fenitrothion (FT) pesticides and on the physical properties of lettuce and cherry tomatoes was examined. The residual FT percentage in lettuce and cherry tomatoes was shown decreased by using higher water temperatures, particularly at 30 °C, resulting in a decrease within the range of 32% to 52%, after the 20-min treatment. In addition, bubbling OMCB treatment did not alter the color and pulling strength of lettuce and cherry tomatoes. These results indicate that bubbling OMCB treatment at 30 °C is a highly effective method for the removal of FT residues in lettuce and cherry tomatoes, with relatively little effect on crop quality. © 2013 Institute of Food Technologists®.

Inactivation kinetics of polyphenol oxidase (PPO) by a two-stage method which was additionally pressurized at ambient temperature after carbon dioxide microbubbles (MB-CO2) was mixed with a solution at low temperature and pressure (two-stage MB-CO2) was analyzed. The PPO inactivation efficiency of the two-stage MB-CO2 treatment was higher than that of heat treatment. A decrease in the decimal reduction time (D value) and activation energy during PPO inactivation using the two-stage MB-CO2 treatment was observed as the temperature of the heating coil and the pressure in the mixing vessel increased. The temperature rise required for a 90% reduction in the D value was increased. Furthermore, the pressure rise required for a 90% reduction in the D value and activation volume increased with the temperature of the heating coil. These results showed that PPO inactivation using the two-stage MB-CO2 treatment could be achieved with less energy than heat treatment. © 2012 Elsevier B.V. All rights reserved.

Green peach aphid is a major pest of various plant such as Solanaceae, Fabaceae and Brassicaceae plants. It is very difficult to control the aphid when they multiply in greenhouse and field. In this study, we focus on neem having pest-control effect against various pests, and set out to develop new biological pesticide against green peach aphid. We searched for neem materials having repellent effect against green peach aphid and determined the effective concentration of neem. Moreover, volatile extract of neem materials was subjected to repellent test against green peach aphid. Neem cake had strong repellent effect against green peach aphid. Neem raw leaves had slight repellent effect whileneem oil had no repellent effect. Volatile extract of 10 g of neem cake showed repellent effect comparable to that of neem cake. These results suggest that volatile components in neem cake have repellent effect on green peach aphid. © ISHS 2013.

The inactivation of Lactobacillus fructivorans suspended in various buffer solutions by low-pressure CO 2 microbubbles (MB-CO 2) was investigated. The number of surviving L. fructivorans cells suspended in 0.1 mol/L acetic acid/0.1 mol/L sodium acetate buffer at pH 4 was decreased by 4-log cycles by MB-CO 2 at 40 °C and 2.0 MPa for 60 min, whereas there were no reductions in the numbers of L. fructivorans cells suspended in 0.1 mol/L citric acid (CA)/0.1 mol/L sodium citrate (NaC) buffer at pH 4, 0.1 mol/L CA/0.2 mol/L disodium hydrogen phosphate (NaP) buffer at pH 4, or 0.1 mol/L CA/0.2 mol/L dipotassium hydrogen phosphate buffer at pH 4 by MB-CO 2 under the same conditions. However, the inactivation of L. fructivorans cells by MB-CO 2 was similar in 0.01 mol/L CA/0.01 mol/L NaC buffer, 0.001 mol/L CA/0.002 mol/L NaP buffer, and deionized water. Furthermore, the inactivating effect of MB-CO 2 tended to increase with decreasing buffer pH. © 2012 Elsevier Ltd.

The ability of carbon dioxide microbubbles (MB-CO 2) to inactivate Lactobacillus fructivorans suspended in physiological saline and unpasteurised sake at ambient temperature and a pressure lower than 2.0MPa was investigated. The number of L. fructivorans cells in physiological saline solution containing 15% ethanol showed a 6-log reduction following MB-CO 2 treatment at 40°C and 2.0MPa for 50min. The effectiveness of the treatment increased concomitantly with temperature, pressure and ethanol concentration of the sample solution but was unaffected by the glucose concentration in the sample solution. Furthermore, the number of L. fructivorans cells showed a 5-log reduction in sake after MB-CO 2 treatment at 40°C and 2.0MPa for 60min. Sensory evaluation revealed no significant difference between MB-CO 2-treated sake and unpasteurised sake. These results indicated that MB-CO 2 treatment was highly effective for the inactivation of L. fructivorans and might become a practical method for pasteurising sake at ambient temperature. © 2012 The Authors. International Journal of Food Science and Technology © 2012 Institute of Food Science and Technology.

As an initial step in developing attractant traps for . Pieris rapae, we identified the attractant significantly preferred by . P. rapae and the best extraction methods for obtaining the extract from cabbage. Cabbage extracts obtained by the diethylether solvent extraction method (DEM), countercurrent-distribution method and Porapak Q column concentration method were analyzed for volatile compounds attractive to . P. rapae. Cabbage extracts were also identified and quantified by gas chromatography-mass spectrometry. . P. rapae showed the highest preference toward the cabbage extract obtained by DEM when compared to the extracts obtained by the other methods. A total of 21 compounds were detected from the highly preferred extract: 4-methyloctane, 2-methylbutanenitrile, propylthiocyanate, d-limonene, methallylcyanide, allyl 2-ethylbutyrate, 1-hexanol, (Z)-3-hexen-1-ol, 3-methoxy-3-methylbutanol, acetic acid, 2-ethyl-1-hexanol, 1,2,4-trithiolane, heptadecane, tridecanol, benzothiazole, 1-undecanol, octadecanal, 2-phenethyl isothiocyanate, 2-nonadecanone 1-heptadecanol, 5,9-dimethyl-3-decanol. Moreover, five compounds from the cabbage extract-dimethyltrisulfide, acetic acid, dimethylsulfoxide, 4-(methylthio) butanenitrile and benzenepropanenitrile-had the highest concentration when obtained by DEM, suggesting that these compounds are the primary attractants to . P. rapae. © 2011 Elsevier Ltd.

To propose ozone microbubbles (O 3MB) as a new disinfection method for the nutrient solution used in hydroponic culture, we investigated the disinfectant effect of O 3MB against Fusarium oxysporum f. sp. melonis and Pectobacterium carotovorum subsp. carotovorum, which are a pathogenic fungus and bacterium that infect plants via the roots, and the effect of O 3MB on the composition of nutrient solution and plant growth. Since O 3MB dissolves more efficiently in solution than O 3 millibubbles (O 3MM) over a short period, it is regarded to be highly effective as a disinfectant against F. oxysporum f. sp. melonis and P. carotovorum subsp. carotovorum. Disinfectant effect was observed when O 3MB treatment was performed once or twice a week at approximately 0.2 ppm of dissolved O 3 in a nutrient solution kept at 20°C. Concentrations of Mn and Fe in the nutrient solution dropped because of O 3MB treatment; however, no effect was observed on other fertilizer components. Furthermore, O 3MB had no adverse effects on the growth of lettuce that was cultivated in this study. While it is necessary to devise a way to counteract the deficiency of Mn and Fe in nutrient solution depending on the cultivated plant, this study suggests that O 3MB can be used as a new disinfectant technique for the nutrient solution used in hydroponic culture. © 2012 ASABE ISSN 1934-2799.

To establish a method for disinfecting hydroponic culture solutions using ozone microbubbles (OMB), we examined the disinfectant activity of OMB against Fusarium oxysporum f. sp. melonis and Pectobacterium carotovorum subsp. carotovorum in infected plant roots. OMB had a higher solubility and remained in the water for a longer period than ozone millibubbles, resulting in extremely high disinfecting activity against both phytopathogens. Furthermore, disinfectant activity and durability of OMB-treated water against both phytopathogens increased with an increase in the initial concentration of dissolved ozone. Therefore, these results suggest that OMB may be suitable for use as a new disinfectant against phytopathogens in hydroponic culture solutions. © 2011 Elsevier Ltd.

We compared the effect of p-chlorophenoxyacetic acid (p-CPA) and 1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU) on parthenocarpic and seeded muskmelon (Cucumis melo) fruits in regards to fruit development and the transport of photoassimilates from leaves exposed to 14CO2 to the developing fruits. Ten days after anthesis (DAA), the fresh weight, total 14C-radioactivity and contents of 14C-sucrose and 14C-fructose were higher in the CPPU-induced parthenocarpic fruits than in seeded fruits. However, at 35 DAA, fresh weight and sucrose content in mesocarp, placenta and empty seeds of the parthenocarpic fruits were lower than in seeded fruits. Also, total 14C-radioactivity and 14C-sugar content of the parthenocarpic fruits were lower as well as the translocation rate of 14C-photoassimilates into these fruits. Application of p-CPA to the parthenocarpic fruits at 10 and 25 DAA increased fresh weight and sugar content. Moreover, these treatments elevated the total 14C-radioactivity, 14C-sucrose content and the translocation rate of 14C-photoassimilates. The 14C-radioactivity along the translocation pathway from leaf to petiole, stem, lateral shoot and peduncle showed a declining pattern but dramatically increased again in the fruits. These results suggest that the fruit's sink strength was regulated by the seed and enhanced by the application of p-CPA. © 2011 Elsevier GmbH.

The effects of ozone microbubbles (OMB) generated by different methods on removal of residual fenitrothion (FT) in three kinds of vegetables were examined. FT-infiltrated lettuce, cherry tomatoes and strawberries were immersed in solutions containing OMB generated by using a microbubble generator of a decompression-type or a gas-water circulating-type combined with an ozone generator at an initial OMB concentration of 2.0 ppm for 0, 5 or 10 min. Residual FT in each vegetable was removed more efficiently by the OMB treatments with the decompression type than with the gas-water circulation type, showing that the pesticide-removing effect of OMB varies with the method of OMB generation. © 2010 Elsevier Ltd. All rights reserved.

The removal of fenitrothion (FT) pesticide residues from vegetables by immersion in ozone-microbubbled solution was demonstrated. FT-treated lettuce, cherry tomatoes, and strawberries were immersed in ozone-microbubbled, ozone-millibubbled, and dechlorinated water. After that the percentage of residual FT in the vegetables was determined. Residual FT was efficiently removed from lettuce by immersing it in ozone-microbubbled solution containing more than 1.0. ppm dissolved ozone, or continuously generated ozone-microbubbled solution containing 2.0. ppm dissolved ozone. Similarly, for cherry tomatoes and strawberries, the continuously generated ozone-microbubbled solution containing 2.0. ppm dissolved ozone was highly effective. These results showed that ozone microbubbles effectively removed residual pesticides not only from leafy vegetables but also from fruity vegetables. © 2010 Elsevier B.V.

Penicillium expansum is an important posfharvest pathogen that not only causes decay on apple and pear fruit but also produces the carcinogenic mycotoxin patulin in spoiled fruit and processed fruit. Although synthetic fungicides are effective to protect against fruit decay, their potential effects on human health and the environment are a concern. Plant extracts are one of several non-chemical control alternatives that inspiring great interest due to their availability, non-toxicity and friendliness to the environment. In this study, screening of antifungal activity against P. expansum from sixteen plants (garlic, clove, dokudami, kumasasa, dandelion, kusagi, yomogi, ginkgo, marigold, lavender, thyme, hot pepper, ginger and lemon basil) by means of solvent extraction with either dichloromethane or diethyl ether was conducted. By the solution contact method and the vapor contact method, plant extraction of 16 plants was treated on PDA and the diameter of a clear inhibition zone was recorded daily for 5 d. Next, 100 μL of conidia suspension was added to each wound on apple fruits. Lesion diameter of the treated fruits was observed daily for 6 d. The antifungal activity against P. expansum of garlic, thyme, lavender, ginkgo and dandelion which directly contacted the fungal spore, was distinguishingly affective with a clear inhibition zone diameter higher than 12 mm over 5 days of incubation. Apple fruits were treated with garlic extracts by the solution contact method. Growth inhibition activity of P. expansum in an amount of 50 μL was higher than that in 20 μL which was equally effective control. Apples exposed to vapor of garlic extract at 1, 2 and 3 ml L -1 for 24, 48 and 72 h show different antifungal effects on P. expansum. Vapor contact of Allium sativum at a concentration of 1 ml L -1 with 72 h of exposure time demonstrated the most optimal performance in terms of fruit appearance. In these results, dichloromethane is an appropriate solvent for use in extracting active compounds from plants presenting antifungal activity against P. expansum. Crude extract of garlic was the most effective, both in the form of solution and vapor contact, for inhibiting mycelium growth of P. expansum. In addition, garlic extract is applicable at relatively low concentration to reduce blue mold rot on apple fruits. © 2011 Asian Network For Scientific Information.

Pieris rapae curucivora Boisduval is a major cause of damage to important Brassicaceae vegetable crops. The method of host landing plant selection by adult females was investigated by covering cabbage (host) and lettuce (non-host) plants to block visual and/or olfactory signals, and also by using volatile extracts of both plants.Numbers of plant landings by pre-mating adult females was much lower than for post-mating females. In addition, the pre-mating females showed no clear preference for the host or non-host plants. These findings suggest that pre-mating females do not actively search for host plants. In contrast numbers of landings increased in post-mating females, immediately after mating, and there was a markedly higher preference for cabbage than lettuce.When plant odors were blocked by covering the plants with transparent or black polyethylene bags there was no difference in the landing preference of adult post-mating females, indicating that the adult females were unable to distinguish between cabbage and lettuce when their olfactory sense was blocked. The greater number of adult females landing on the plants covered with transparent polyethylene bags than those covered with black bags indicated that the females recognize the plants visually. When the transparent and black polyethylene bags had holes that enabled olfactory signals to reach the females, there was a clear preference for cabbage over lettuce. These results together with a preference for lettuce plants treated with cabbage volatile extracts than lettuce plants treated with lettuce volatile extracts indicate that the adult females detect host plants using their olfactory sense. © 2010 Elsevier Ltd.

Cut vegetables have become popular among consumers in the past few decades. Washing with sodium hypochlorite (NaOCl) solution is the most common method used for preventing cut vegetables from spoiling, but some organic compounds react easily with available chlorine to form toxic chlorinated products. Thus, other disinfection methods to replace NaOCl treatment are being explored. We previously devised an instrument with CO2 micro-and nano-bubbles under pressure less than 2.0 MPa (MNB-CO2) for inactivating microorganisms in food at room temperature. The aim of this study was to investigate the effect of MNB-CO2 on the inactivation of microorganisms in cut wakegi (Allium wakegi Araki), which are difficult to inactivate with NaOCl. MNB-CO2 treatment was conducted at each condition of pressure (0.1∼2.0 MPa), temperature (20∼30°C) and solution pH (3.0∼6.5) for 10∼30 min. Also, for comparison, cut wakegi was immersed in 100 ppm NaOCl solution at 20∼30°C for 10∼30 min and washed for 5 min to remove residual NaOCl. Total and coliform bacteria in cut wakegi were effectively inactivated by MNB-CO2. The inactivation effect of MNB-CO2 treatment was almost the same as that of NaOCl treatment. The number of total and coliform bacteria significantly decreased with increasing pressure and temperature in the MNB-CO2 treatment, and was especially decreased with decreasing solution pH. These results suggested that MNB-CO2 treatment at pressure less than 2.0 MPa and room temperature was very effective at inactivating microorganisms in cut wakegi as an alternative to NaOCl treatment.

The leaves of coriander (Coriandrum sativum L.) exhibited a strong deodorizing effect against porcine internal organs (large intestine). The effective deodorizing compounds of coriander were identified by separating the volatile component of coriander, testing the effectiveness of each fraction against the offensive odor of porcine large intestine, and then identifying the compounds by GC-MS. The volatile component of coriander was first separated into six fractions (A-F) by preparative gas chromatography, and the deodorizing activity of each of these fractions against the offensive odor was measured. Fraction D, which showed the strongest deodorizing effect, was then separated into 12 subfractions by preparative GC. The deodorant activity of each subfraction was evaluated, and the deodorant compounds were identified by GC-MS. It was discovered that (E,E)-2,4-undecadienal was the most effective deodorizing compound. The deodorizing activity of (E,E)-2,4-undecadienal on the porcine large intestine increased as with concentration, reaching almost complete deodorizing ability at 10 ppb. © 2010 American Chemical Society.

The ability of CO 2 microbubbles (MB-CO 2) to inactivate Saccharomyces cerevisiae suspended in a physiological saline solution at a pressure lower than 2.0 MPa was investigated. A 6-log reduction in the S. cerevisiae population was induced by MB-CO2 at 40° C and 2.0 MPa after a 50 min treatment in a physiological saline solution with 5.0% ethanol, and a 3-log reduction was induced by low-pressurized CO 2 under the same conditions. Furthermore, the ability of MB-CO2 to inactivate S. cerevisiae increased concomitant with increasing the CO 2 feeding rate, pressure, temperature, and ethanol concentration in a physiological saline solution. Additionally, the decimal reduction time (D value) in the inactivation of S. cerevisiae by the MB-CO 2 treatment might depend on the saturation value of the dissolved CO 2 concentration in the solution. These results suggested that MB-CO 2 treatment could inactivate S. cerevisiae in a low-concentration ethanol solution at 40° C to 45° C and at a pressure of 1.0 to 2.0 MPa. © 2010 American Society of Agricultural and Biological Engineers ISSN 2151-0032.

To investigate the effect of a deoxygenating agent (deoxy) and a nitrogen-atmosphere package (nitro) on the quality, especially flavor, of Koshihikari stored at 30°C for 12 months, volatile compounds of the cooked stored rice were analyzed by gas chromatography-olfactometry (GC-O), GC-mass spectrometry and sensory evaluation. Sensory evaluation revealed that the deoxy-rice was very similar in quality to non-stored rice (fresh-rice), although the non-treated stored rice (control-rice) and nitro-rice had a stale flavor and undesirable taste. Furthermore, GC-O analysis indicated that the number of volatile compounds in the deoxy- and fresh-rice was significantly less than in the control- and nitro-rice. Therefore, it was suggested that the technique of storing harvested rice with a deoxygenating agent could maintain the flavor of harvested rice at room temperature.

The ability of CO 2 microbubbles (MB-CO 2) to inactivate Escherichia coli suspended in a saline solution at a pressure lower than 2.0 MPa was investigated. A 6-log reduction in E. coli population occurred with MB-CO 2 at 40° C and 2.0 MPa after 60 min treatment, and a slight reduction occurred with low-pressurized CO 2 under the same conditions. The dissolved CO 2 concentration in the solution with MB-CO 2 was much higher than that with low-pressurized CO 2. On the other hand, E. coli could not be inactivated with N 2 microbubbles instead of CO 2 under the same conditions. The ability of MB-CO 2 to inactivate E. coli increased concomitant with increasing the CO 2 feeding rate, pressure, and temperature. These results demonstrate that, with the experimental conditions and apparatus used in this study, MB-CO 2 could very effectively inactivate E. coli at a temperature of 30° C to 40° C and at a pressure of 0.5 to 2.0 MPa. © 2009 American Society of Agricultural and Biological Engineers ISSN 0001-2351.