低场核磁及成像技术原位监测温度对刺参干燥过程中水分流动性的影响
|
摘要
选取45、60和75℃3个温度对刺参进行原位干燥,利用低场核磁及成像技术原位监测刺参干燥过程中的水分动态变化。结果表明,3个温度条件下的横向弛豫时间图谱均有3个峰,分别为弛豫时间小于2ms的结合水、15～183ms的不易移动水、200～1 600ms的自由水。结合水的峰比例为上升趋势,不可移动水的峰比例总体下降趋势,但有波动,自由水峰比例先升后降。磁共振成像可以看出,在同样干燥12h条件下,75℃时干燥水分变化明显,说明此温度下干燥速率最大。
Three different temperatures(45,60 and 75 ℃)were used for dehydration of Stichopus japonicas samples in situto investigate the effect of temperature on transverse relaxation time T2 using low field-nuclear magnetic resonance(LF-NMR)equipped with a variable temperature probe.The results suggested that three different kinds of peaks were observed with T2 relaxation profile of less than 2ms,15-183,200-1 600 ms,corresponding to bound water,immobilized portion and free fraction,respectively.The proportion of bound water showed an ascending trend while proportion of immobilized water exhibited an opposite trend generally but fluctuated irregularly.The free water proportion increased firstly then decreased without regularity.MRI result showed that the water loss was the most prominent when Stichopus japonicas were dried at 75℃,confirming the drying rate was the highest.
Three different temperatures(45,60 and 75 ℃)were used for dehydration of Stichopus japonicas samples in situto investigate the effect of temperature on transverse relaxation time T2 using low field-nuclear magnetic resonance(LF-NMR)equipped with a variable temperature probe.The results suggested that three different kinds of peaks were observed with T2 relaxation profile of less than 2ms,15-183,200-1 600 ms,corresponding to bound water,immobilized portion and free fraction,respectively.The proportion of bound water showed an ascending trend while proportion of immobilized water exhibited an opposite trend generally but fluctuated irregularly.The free water proportion increased firstly then decreased without regularity.MRI result showed that the water loss was the most prominent when Stichopus japonicas were dried at 75℃,confirming the drying rate was the highest.
引文
[1]张绪坤,祝树森,黄俭花,等.用低场核磁分析胡萝卜切片干燥过程的内部水分变化[J].农业工程学报,2012,28(22):282-287.
[2]段续,王辉,任广跃,等.海参的干制技术及其研究进展[J].食品工业科技,2012,33(10):427-431.
[3]张建锋,吴迪,龚向阳,等.基于核磁共振成像技术的作物根系无损检测[J].农业工程学报,2012,28(8):181-185.
[4]夏天兰,刘登勇,徐幸莲,等.低场核磁共振技术在肉与肉制品水分测定及其相关品质特性中的应用[J].食品科学,2011,32(21):253-256.
[5]孟维博,刘燕,伍国杰,等.不同干燥方法对牡蛎干品质及气味的影响[J].食品科技,2015,40(6):174-179.
[6]SONG Y K,ZANG X,KAMAL T,et al.Real-time detection of water dynamics in abalone(Haliotis discus hannaiino)during drying and rehydration processes assessed by LF-NMR and MRI[J].Drying Technology,2018,36(1):72-83.
[7]GENG S T,WANG H,WANG X,et al.A non-invasive NMR and MRI method to analyze the rehydration of dried sea cucumber[J].Analytical Methods,2015,7(6):2413-2419.
[8]HUANG L L,CHENG S S,SONG Y K,et al.Non-destructive analysis of caviar compositions using low-field nuclear magnetic resonance technique[J].Journal of Food Measurement and Characterization,2017,11(2):621-628.
[2]段续,王辉,任广跃,等.海参的干制技术及其研究进展[J].食品工业科技,2012,33(10):427-431.
[3]张建锋,吴迪,龚向阳,等.基于核磁共振成像技术的作物根系无损检测[J].农业工程学报,2012,28(8):181-185.
[4]夏天兰,刘登勇,徐幸莲,等.低场核磁共振技术在肉与肉制品水分测定及其相关品质特性中的应用[J].食品科学,2011,32(21):253-256.
[5]孟维博,刘燕,伍国杰,等.不同干燥方法对牡蛎干品质及气味的影响[J].食品科技,2015,40(6):174-179.
[6]SONG Y K,ZANG X,KAMAL T,et al.Real-time detection of water dynamics in abalone(Haliotis discus hannaiino)during drying and rehydration processes assessed by LF-NMR and MRI[J].Drying Technology,2018,36(1):72-83.
[7]GENG S T,WANG H,WANG X,et al.A non-invasive NMR and MRI method to analyze the rehydration of dried sea cucumber[J].Analytical Methods,2015,7(6):2413-2419.
[8]HUANG L L,CHENG S S,SONG Y K,et al.Non-destructive analysis of caviar compositions using low-field nuclear magnetic resonance technique[J].Journal of Food Measurement and Characterization,2017,11(2):621-628.