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The purpose of this study is to investigate denaturation kinetics of 7S and 11S proteins as well as lipoxygenase in soymilk during ohmic heating treatment. Because denaturation kinetics of 7S and 11S are nth‐order reaction, a reaction order was estimated based on experimental data and simulation results using Arrhenius parameters calculated through differential scanning calorimetry dynamic method. Denaturation kinetic of lipoxygenase was determined by denaturation ratio which estimated based on oxygenase activity of its after ohmic heating treatment at 65, 70, and 72.5°C. The reaction orders of 7S and 11S proteins during ohmic heating of raw soymilk were determined as 3.25 and 1.52, respectively; while the reaction order of 11S protein in preheated soymilk at 75°C for 1 h was found to be 1.94 with a good correlation between experimental data and simulation result. Electrophoresis results indicated that trypsin inhibitor might affect the denaturation of 11S protein during ohmic heating. The denaturation of lipoxygenase during ohmic heating followed a first‐order reaction at all temperatures, and denaturation simulation using the Arrhenius parameters corresponded well with the experimental data. Practical Applications: This study provides valuable insights into improving a quality of soymilk products. 7S and 11S proteins play a critical role in determining viscosity of soymilk and tofu made from soymilk, which together account for a large proportion of the total proteins in soymilk. Understanding the thermal denaturation kinetics of 7S and 11S proteins can help food manufacturers optimize their processing parameters to achieve the desired physical properties of soymilk. Moreover, lipoxygenase is responsible for producing beany flavor components in soymilk, and understanding its thermal denaturation kinetic can lead to production of soymilk with high consumer acceptance. Our research supports a practical application of ohmic heating technology in the processing of soymilk. [ABSTRACT FROM AUTHOR]

BACKGROUND: Soymilk is utilized not only as a beverage but also as an alternative to bovine milk, including products such as yoghurt and cream. Evaporated soymilk is expected to be utilized as condensed milk. Raw and heated soymilk samples prepared in our laboratory were evaporated and then subjected to viscosity measurement. The soymilk samples were made from two different varieties: Fukuyutaka, which contains 7S and 11S globulin proteins; and an 11S‐lacking soybean (Nanahomare). RESULTS: Raw Fukuyutaka soymilk had a lower viscosity and could be concentrated to a solids content of over 300 g kg−1 compared to heated soymilk (around 250 g kg−1), but the viscosity changes of Nanahomare soymilk showed an opposite trend. Only 7S globulin was denatured during evaporation at 75 °C and likely affected the interaction between proteins and oil bodies. This tendency was remarkable in the Nanahomare soymilk. The strange viscosity change behavior of evaporated Nanahomare soymilk, number of protein particles, intrinsic fluorescence and flow behavior suggest that thermally denatured 7S globulin accelerates the interactions between oil bodies, whereas 11S globulin, which is probably in its native state, suppresses the acceleration by denatured 7S globulin. CONCLUSION: Raw soymilk containing native globulins shows a slower increase in viscosity during evaporation. However, denatured 7S globulin accelerates the increase in viscosity during evaporation through interactions between oil bodies. The effect of the denatured state of individual proteins on interactions is expected to be useful in understanding the interaction between proteins and in controlling their properties and functions. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The effects of high‐temperature supercritical CO2 (SC‐CO2) extraction on Z‐isomerization and recovery of carotenoids (astaxanthin, adonirubin, and adonixanthin) from Paracoccus carotinifaciens are investigated. The high‐temperature extraction, especially at >100 °C, not only increases the total Z‐isomer ratio of carotenoids in the resulting extracts but also improves carotenoid recovery. For example, when the SC‐CO2 extraction is performed at 60 °C and 30 MPa with an entrainer (ethanol), the total Z‐isomer ratio and the recovery of astaxanthin are 11.1% and 28.4%, respectively, whereas at 120 °C, the values increase to 54.2 and 56.4%, respectively. The significant improvement in the extraction efficiency of carotenoids at high temperatures can be attributed to the increase in the ratio of carotenoid Z‐isomers with high solubility in SC‐CO2. Moreover, the effects of extraction pressure and entrainer content on Z‐isomerization and recovery of carotenoids are also investigated. The results show that higher pressure and ethanol content resulted in lower Z‐isomer ratios and higher recoveries of carotenoids. As the Z‐isomers of carotenoids have greater bioavailability and potentially exhibit superior biological activities than the all‐E‐isomers, high value‐added carotenoids, and higher yield can be simultaneously achieved with high‐temperature extraction. Practical applications: As carotenoid extraction is usually performed using toxic organic solvents, residual solvents are a serious concern. In addition, naturally occurring carotenoids (mainly the all‐E‐isomers) have low bioavailability. These are important issues that need to be overcome for the industrial use of carotenoids. The Z‐isomer‐rich carotenoids obtained by SC‐CO2 extraction under high‐temperature conditions have great potential to solve these issues simultaneously. [ABSTRACT FROM AUTHOR]

New aminosilanes with hydrolysable Si-N bond(s) were prepared by the amination of chlorosilanes and used as hydrophobic modifiers of SiO2 surface. The aminosilanes are rather stable towards hydrolysis in air compared to their chlorosilane analogs. The modified SiO2 was applied as a gate insulator of an organic thin-film transistor with a vapor-deposited film of pentacene as the active material. The transistor with the aminosilane-modified SiO2 showed two- to threefold higher hole mobility than the device with bare SiO2. [ABSTRACT FROM AUTHOR]

This study aims to improve the efficiency of lycopene extraction from gac (Momordica cochinchinensis Spreng.) by the Z‐isomerization induced with microwave irradiation pre‐treatment. Although 93.6% of lycopene exist as all‐E‐isomers in dried gac aril, the total Z‐isomer content reaches 35.6 and 58.5% by microwave irradiation at 900 W for 40 s and at 1050 W for 60 s, respectively. The 35.6 and 58.5% Z‐isomerization treatment improves lycopene content of extract (by 6.0 or 8.5 times for press extraction, 7.8 or 13.5 times for ethanol extraction, and 4.5 or 6.1 times for supercritical CO2 (SC‐CO2)extraction, respectively) compared with no treatment. In addition, the extracts containes high amounts of lycopene Z‐isomers, which have higher bioavailability and antioxidant capacity than (all‐E)‐lycopene. Practical Applications: This study clearly shows that lycopene recovery by press, organic solvent, and SC‐CO2 extraction from dried gac aril improved by the increase in the Z‐isomer content. It indicates that the Z‐isomers are more soluble in oil, organic solvent, and SC‐CO2 than the all‐E‐isomer. Moreover, the thermal Z‐isomerization pre‐treatment increases the content of lycopene Z‐isomers in the extract. Therefore, this procedure is important not only for improving the productivity of lycopene, but also for providing a highly functionalized extract. The effect of the Z‐isomerization, induced by microwave irradiation pre‐treatment of gac (Momordica cochinchinensis Spreng.) aril, on the lycopene recovery and lycopene content of the extracts obtained using press, ethanol, and SC‐CO2 extractions is investigated. For all extraction methods, as the content of Z‐isomers in the raw material increases, the recovery and lycopene content of gac extracts improve. [ABSTRACT FROM AUTHOR]