Pulsed electric field is an innovative method for non-thermal food processing. The effects of pulsed electric field on cell disintegration and mass transfer in sugar beet were studied. Sugar beet slices were treated b...Pulsed electric field is an innovative method for non-thermal food processing. The effects of pulsed electric field on cell disintegration and mass transfer in sugar beet were studied. Sugar beet slices were treated by various Field strengths （0.5-6 kV cm^-1）, capacity of capacitors （0.5, 8 and 32 μF） and pulse numbers （1-100 pulses）. The cell disintegration index and energy input for each treated sample was evaluated. The results showed that the cell membrane of PEF （Pulsed Electric Field） treated samples using 2 kV cm^-1, 8 μF after 20 pulses, and 3 kV cm1, 8 μF after 10 pulses were rapidly disintegrated in less than 1 min. Most important parameters during cell permeabilization were the total energy input followed by field strength. Energy efficiency index was defined as cell disintegration index per energy input unit. The maximum efficiency index was achieved using 2 kV cm^-1, 8 μF after 5 pulses. Comparison between PEF pretreatment and thermal method showed that large amount of sugar may be extracted after PEF pretreatment using field strength of 2 Kv cm^-1, 8μF in less than 10 min at ambient temperature. In.addition, the consumed energy for thermal treatment was approximately 20 to 50 times more than PEF pretreatment. Optimizing the field conditions in PEF treatment is an important factor to achieve high amount of sugar extraction from sugar beet.展开更多
High intensity pulsed electric fields(PEF)combined with distillation was used to extract essential oil from rose.Three main parameters,namely electric field intensity,pulse number and distillation times,which can affe...High intensity pulsed electric fields(PEF)combined with distillation was used to extract essential oil from rose.Three main parameters,namely electric field intensity,pulse number and distillation times,which can affect the efficiency of extraction,were optimized.Then,in order to demonstrate the feasibility of the method,oil obtained under optimal conditions was compared quantitatively and qualitatively with that obtained by conventional hydro distillation.Considering the extraction yield,the optimal parameters combination was obtained with electric field intensity of 20 kV/cm,pulse number of 8 and distillation time of 2 h.PEF treatment had no significant influence on the quality of essential oils.However,there was an increase in methyl eugenol percentage,which is a disadvantage from qualitative point of view.展开更多
脉冲电场(Pulsed electric fields,PEF)是一种新型物理场加工技术,具有处理时间短、能耗低以及绿色环保等优点,近年来在回收农产品加工废弃物中活性物质的应用上展现出一定的潜力。本文对脉冲电场强化活性物质提取的作用机理以及优点进...脉冲电场(Pulsed electric fields,PEF)是一种新型物理场加工技术,具有处理时间短、能耗低以及绿色环保等优点,近年来在回收农产品加工废弃物中活性物质的应用上展现出一定的潜力。本文对脉冲电场强化活性物质提取的作用机理以及优点进行了综述。此外,本文也针对脉冲电场技术在回收不同类型加工废弃物中活性物质的应用进展进行了分类和详细概述,以期为农产品加工过程中副产物的高值化利用提供参考和指导。展开更多
In this study,the synthetic peptide Leu-Tyr-Gly-Ala-Leu-Gly-Leu(LYGALGL)derived from egg white was used as the research object.The structure-activity relationship was elucidated by cell experiment and structure determ...In this study,the synthetic peptide Leu-Tyr-Gly-Ala-Leu-Gly-Leu(LYGALGL)derived from egg white was used as the research object.The structure-activity relationship was elucidated by cell experiment and structure determination.The results of cell experiment showed that the superoxide dismutase(SOD)activity and mitochondrial membrane potential(MMP)of LYGALGL were significantly increased by pulsed electric field(PEF)treatment,especially by 10 kV/cm field intensity treatment(P<0.05).However,the content of reactive oxygen species(ROS)decreased significantly(P<0.05).LYGALG treated with 10 kV/cm showed the highest antioxidant activity.The results of structure determination showed that theβ-turn of LYGALGL increased,the random coil decreased,and the active hydrogen sites moved under 10 kV/cm treatment.The structure of LYGALGL was changed and the active site was exposed by PEF,thus improving the antioxidant activity of LYGALGL.展开更多
文摘Pulsed electric field is an innovative method for non-thermal food processing. The effects of pulsed electric field on cell disintegration and mass transfer in sugar beet were studied. Sugar beet slices were treated by various Field strengths （0.5-6 kV cm^-1）, capacity of capacitors （0.5, 8 and 32 μF） and pulse numbers （1-100 pulses）. The cell disintegration index and energy input for each treated sample was evaluated. The results showed that the cell membrane of PEF （Pulsed Electric Field） treated samples using 2 kV cm^-1, 8 μF after 20 pulses, and 3 kV cm1, 8 μF after 10 pulses were rapidly disintegrated in less than 1 min. Most important parameters during cell permeabilization were the total energy input followed by field strength. Energy efficiency index was defined as cell disintegration index per energy input unit. The maximum efficiency index was achieved using 2 kV cm^-1, 8 μF after 5 pulses. Comparison between PEF pretreatment and thermal method showed that large amount of sugar may be extracted after PEF pretreatment using field strength of 2 Kv cm^-1, 8μF in less than 10 min at ambient temperature. In.addition, the consumed energy for thermal treatment was approximately 20 to 50 times more than PEF pretreatment. Optimizing the field conditions in PEF treatment is an important factor to achieve high amount of sugar extraction from sugar beet.
文摘High intensity pulsed electric fields(PEF)combined with distillation was used to extract essential oil from rose.Three main parameters,namely electric field intensity,pulse number and distillation times,which can affect the efficiency of extraction,were optimized.Then,in order to demonstrate the feasibility of the method,oil obtained under optimal conditions was compared quantitatively and qualitatively with that obtained by conventional hydro distillation.Considering the extraction yield,the optimal parameters combination was obtained with electric field intensity of 20 kV/cm,pulse number of 8 and distillation time of 2 h.PEF treatment had no significant influence on the quality of essential oils.However,there was an increase in methyl eugenol percentage,which is a disadvantage from qualitative point of view.
文摘脉冲电场(Pulsed electric fields,PEF)是一种新型物理场加工技术,具有处理时间短、能耗低以及绿色环保等优点,近年来在回收农产品加工废弃物中活性物质的应用上展现出一定的潜力。本文对脉冲电场强化活性物质提取的作用机理以及优点进行了综述。此外,本文也针对脉冲电场技术在回收不同类型加工废弃物中活性物质的应用进展进行了分类和详细概述,以期为农产品加工过程中副产物的高值化利用提供参考和指导。
基金supported by the National Key Research and Development Program of China(2017YFD0400504).
文摘In this study,the synthetic peptide Leu-Tyr-Gly-Ala-Leu-Gly-Leu(LYGALGL)derived from egg white was used as the research object.The structure-activity relationship was elucidated by cell experiment and structure determination.The results of cell experiment showed that the superoxide dismutase(SOD)activity and mitochondrial membrane potential(MMP)of LYGALGL were significantly increased by pulsed electric field(PEF)treatment,especially by 10 kV/cm field intensity treatment(P<0.05).However,the content of reactive oxygen species(ROS)decreased significantly(P<0.05).LYGALG treated with 10 kV/cm showed the highest antioxidant activity.The results of structure determination showed that theβ-turn of LYGALGL increased,the random coil decreased,and the active hydrogen sites moved under 10 kV/cm treatment.The structure of LYGALGL was changed and the active site was exposed by PEF,thus improving the antioxidant activity of LYGALGL.
