Effect of Thermosonic Pretreatment and Microwave Vacuum Drying on the Water State and Glass Transition Temperature in Agaricus bisporus Slices
Effect of Thermosonic Pretreatment and Microwave Vacuum Drying on the Water State and Glass Transition Temperature in Agaricus bisporus Slices
复制标题
热超声预处理和微波真空干燥对双孢蘑菇切片水状态和玻璃化转变温度的影响
DOI：
10.1007/s11947-017-2004-2
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发表时间：
2018-01-01
影响因子：
5.6
通讯作者：
Yu, Zhifang
中科院分区：
文献类型：
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作者：
Jiang, Ning;Liu, Chunquan;Yu, Zhifang
研究了双孢蘑菇热超声预处理和微波真空干燥的微观机理。采用差示扫描量热法（DSC）、低场核磁共振（LF-NMR）和磁共振成像（MRI）研究了微波真空干燥过程中新鲜和热超声处理的双孢蘑菇切片的水分状态和玻璃化转变温度（T-g）。结果表明，新鲜的A.双孢切片：T-21（0.38-7.05 ms）、T-22（9.33-32.75 ms）、T-231（37.65-265.61 ms）和T-232（305.39-811.13 ms）。热超声预处理显著降低了A.双孢菌样品，但伴随着其固定水急剧增加。微波真空干燥（MVD）过程中，水分含量（X-w）为0.70和0.60 g/g（湿基（w.b.）分别用于未处理的和热超声处理的样品。微血管化使固定化水含量和流动性降低，从而使水的状态发生显著变化，提高了玻璃化转变温度。双孢组织热超声处理和MVD处理的样品的半结合水的流动性高于MVD未处理的样品，导致T-g值降低约2-11.5 A ℃，但热超声处理和MVD处理的样品中的水分布的均匀性在X-w
This study aimed to understand the micromechanism of thermosonic pretreatment and microwave vacuum drying on Agaricus bisporus. The water state and glass transition temperature (T-g ) of fresh and thermosonically treated Agaricus bisporus slices during microwave vacuum drying were studied using differential scanning calorimetry (DSC), low-field nuclear magnetic resonance (LF-NMR), and magnetic resonance imaging (MRI). Results showed that four population groups were contained in the initial distribution of transverse relaxation time (T-2) data of fresh A. bisporus slices: T-21 (0.38-7.05 ms), T-22 (9.33-32.75 ms), T-231 (37.65-265.61 ms), and T-232 (305.39-811.13 ms). Thermosonic pretreatment significantly decreased the initial free water content of A. bisporus sample but was accompanied by a sharp increase in its immobilized water. "Semi-bound water transfer" appeared during microwave vacuum drying (MVD) at moisture contents (X-w ) of 0.70 and 0.60 g/g (wet basis (w.b.)) for untreated and thermosonically treated samples, respectively. MVD caused dramatic changes in the water state and enhanced the T-g by decreasing the content and mobility of immobilized water in A. bisporus tissues. The mobility of semi-bound water for thermosonically and MVD-treated samples was higher than for MVD-untreated samples, resulting in T-g values decreasing by approximately 2-11.5 A degrees C, but the uniformity of water distribution in thermosonic-treated and MVD-treated samples was better at X-w