We supercooled fresh-cut onion at−5℃ for 12 h.After supercooling,the electric impedance properties of the samples were evaluated by electrical impedance spectroscopy over the frequency range of 42 Hz−5 MHz.The time-t...We supercooled fresh-cut onion at−5℃ for 12 h.After supercooling,the electric impedance properties of the samples were evaluated by electrical impedance spectroscopy over the frequency range of 42 Hz−5 MHz.The time-temperature profiles of samples indicated that the freezing point and supercooling point were−2.3℃±0.7℃ and−6.9℃±1.0℃,respectively.The results indicated that 34 of the 36 supercooled samples exhibited a definite circular arc in the Cole-Cole plot,which suggested that the cell membrane remained intact during supercooling.In the other two samples which did not exhibit a definite circular arc,the cell membrane had sustained serious damage during supercooling.Furthermore,there was large difference in drip loss percentage between supercooled samples exhibited a definite circular arc in the Cole-Cole plot and samples not exhibiting a definite circular arc.Our results suggest that fresh-cut onions can be supercooled at−5℃.展开更多
基金This work was supported by JSPS KAKENHI,grant number JP16H05001[Grant-in-Aid for Scientific Research(B)]JP16K15010[Grant-in-Aid for Exploratory Research].
文摘We supercooled fresh-cut onion at−5℃ for 12 h.After supercooling,the electric impedance properties of the samples were evaluated by electrical impedance spectroscopy over the frequency range of 42 Hz−5 MHz.The time-temperature profiles of samples indicated that the freezing point and supercooling point were−2.3℃±0.7℃ and−6.9℃±1.0℃,respectively.The results indicated that 34 of the 36 supercooled samples exhibited a definite circular arc in the Cole-Cole plot,which suggested that the cell membrane remained intact during supercooling.In the other two samples which did not exhibit a definite circular arc,the cell membrane had sustained serious damage during supercooling.Furthermore,there was large difference in drip loss percentage between supercooled samples exhibited a definite circular arc in the Cole-Cole plot and samples not exhibiting a definite circular arc.Our results suggest that fresh-cut onions can be supercooled at−5℃.