摘要
利用低场核磁共振技术对樱桃在常温储存条件下内部水分的变化、迁移规律进行了研究。采用CMPG脉冲序列测量自由诱导指数衰减曲线,并对曲线进行反演操作,得到了横向弛豫时间T2谱。结果表明,樱桃内部水分主要存在自由水、不易流动水、结合水3种状态,自由水含量随储存时间不断减少,一部分蒸发散失到外界,另一部分和大分子结合为结合水与不易流动水,以维持果肉细胞正常的代谢活动。在储存后期,部分自由水向果核迁移,保证核内有足够的水分和活性。核磁共振成像实验结果表明,随着储存时间的延长,果皮与果肉分层,果肉水分逐渐向内迁移,与T2谱分析结果一致。
The change and migration law of moisture in cherry stored at room temperature was researched by low-field nuclear magnetie resonance （NMR） technology. Free induction exponential decay curve was measured by using CPMG pulse sequences, transverse relaxation time T2 was obtained by inversion operation. The experimental results showed that cherry＇s internal moisture mainly existed three states： free water, immobilized water and bound water, the content of t~＇ee water reduced continuously with the storage time, a part of free water evaporated to the outside, and other part of free water ehanged into immobilized water and bound water, in order to maintain the normal metabolism of pulp cells. At the later storage period, part of free water migrated to the core for enough moisture and activity. The NMR imaging results showed that peel and flesh of cherry layered, and moisture migrated in cherry from surface to the inner with the extension of storage time, analysis results were consistent with the T2 spectra.
出处
《实验室研究与探索》
CAS
北大核心
2013年第8期52-54,共3页
Research and Exploration In Laboratory
基金
北京科技大学研究型教学示范课建设项目(JY2011SFK18)
北京科技大学教育教学改革研究项目(重点)(JG2011Z14)
北京科技大学2012年本科生科技创新项目
关键词
樱桃
低场核磁共振
横向弛豫时间
cherry
low-field nuclear magnetic resonance
transverse relaxation time
