椰子的成熟度和贮藏品质的介电评估方法  

Assessment of Maturity and Storage Quality of Coconut by Dielectric Relaxation Spectroscopy

作　　者：刘媛[1] 高艳艳[1] 杨曼[1] 范小青[1] 赵孔双[1] 赵少杰[2] 

机构地区：[1]北京师范大学化学学院,北京100875 [2]北京师范大学遥感科学国家重点实验室,北京100875

出　　处：《食品科学》2016年第14期225-230,共6页Food Science

基　　金：国家自然科学基金面上项目(21173025;21473012)

摘　　要：利用介电弛豫谱方法对椰子成熟度以及椰子水的贮藏温度和时间进行了研究。由于椰子水中蔗糖的质量浓度与成熟度有关,因此利用椰子水-蔗糖混合溶液的电导率与蔗糖质量浓度的依存关系,可以判断椰子的相对成熟度。低频电导率谱结果显示,椰子水的电导率随着贮藏时间的延长而逐渐降低,并且室温条件下贮藏时,电导率降低得更快,说明低温更利于椰子水的贮藏。此外,微波段弛豫实际包含了自由水分子和结合水分子两部分贡献,其中结合水分子弛豫强度的变化可以反映椰子水品质的改变。椰子水不同时间的颜色变化说明,开壳椰子水在室温条件下可以保存1 d,而在冰箱中可以保存3 d。The maturity, storage temperature and time of coconut water were investigated by dielectric relaxation spectroscopy. The sucrose concentration in coconut water was found to be related to its maturity, allowing the determination of the relative maturity of coconut water. The conductivity of coconut water decreased when the storage time was extended, and declined faster at room temperature, indicating that low temperature is favorable for the storage of coconut water. Besides, both free and bound water contributed to the relaxation of coconut water at microwave frequencies. The change in relaxation strength of bound water reflected the quality change of coconut water. The color change of coconut water indicated that coconut water could be stored for one day at room temperature and for three days in refrigerator.

关 键 词：介电弛豫谱 椰子水 成熟度 贮藏 品质 

分 类 号：O645.1[理学—物理化学] O487[理学—化学]