基于低场核磁共振技术对不同干燥方式的海马品质研究

Effects of different drying methods on quality of sea horse Hippocampus based on low-field nuclear magnetic resonance technology

为探究不同干燥方式对海马Hippocampus品质特性的影响,采用热风干燥(100℃)、冷风干燥(40℃)、真空冷冻干燥(-26~-30℃,0.1 kPa)和真空干燥(70℃,133 Pa)等方式对三斑海马Hippocampus trimaculatus(湿体质量2.5~3.0 g)进行处理,测定并分析了海马干在不同干燥方式下的干燥性能、收缩率、水分分布等指标。结果表明:不同干燥方式对三斑海马的干燥性能、收缩率有显著性影响(P<0.05),其中,热风干燥与真空干燥的耗时和耗能分别为15 h、4.03 kW·h/kg和10 h、2.46 kW·h/kg,干燥性能较优,而真空冷冻干燥的收缩率最低;低场核磁检测结果显示,不同干燥方式的干燥过程中海马干的水分含量下降,主要是不易流动水和自由水含量降低;海马干复水过程的结果显示,不易流动水不断上升,热风干燥和真空冷冻干燥的复水速度较快。研究表明,热风干燥与真空干燥用时短,具有节能效果,而真空冷冻干燥处理的海马品质较优,复水性能较好。

In order to explore the effect of different drying methods on quality characteristics of sea horse Hippocampus,the drying performance,shrinkage rate and moisture distribution were measured and analyzed in longnose sea horse Hippocampus trimaculatus with wet body mass of 2.5-3.0 g dried by 100℃hot air drying,40℃cold air drying,vacuum freeze-drying(-26--30℃,0.1 kPa)and vacuum drying(70℃,133 kPa).The results showed that the drying performance and shrinkage rate of longnose sea horse were significantly affected by different drying methods(P<0.05).The better drying performance was observed in hot air drying and vacuum drying,with the time consumption of 15 h,and energy consumption of 4.03 kW·h/kg in the hot air drying and 10 h,2.46 kW·h/kg in the vacuum hot air drying,and the minimal shrinkage rate in vacuum freeze-drying.Low field nuclear magnetic resonance detection revealed that the moisture content was decreased in different drying methods,primarily due to the decrease in the content of immobilized water and free water.The change in the rehydration process of longnose sea horse showed that the immobilized water was increased continuously,and the faster rehydration speed was found in the hot air drying and vacuum freeze drying.It is concluded that drying and vacuum drying are characterized by short time and energy saving,and that the sea horse treated by vacuum freeze-drying has high quality and good rehydration performance.