远红外辅助热风干燥对秋刀鱼片干燥特性及品质的影响

为探究远红外辅助热风干燥对秋刀鱼片干燥特性和品质的影响,采用远红外辅助热风干燥和热风干燥工艺在50、60、70、80和90 ℃下对秋刀鱼片进行脱水处理,并观察其品质变化情况。结果表明:为使秋刀鱼片的干基含水率降低至43%以下,50~90 ℃热风干燥所需的干燥时间分别为570、435、282、225、208 min,远红外联合热风干燥所需时间为510、395、258、204、186 min,提高干燥温度有利于缩短干燥时间和提高干燥速率,且远红外联合热风干燥具有明显的干燥优势。低场核磁共振的检测结果显示,干燥过程秋刀鱼片中的不易流动水转化为自由水向外扩散进而实现干燥的目的。在干燥品质方面,干燥后秋刀鱼片的红度a^*值和黄度b^*值分别增加至4.85~8.98和12.08~16.01;随干燥温度的增加,硬度、咀嚼性、回复性等质构指标和气味、鲜味、咀嚼性等感官评分呈上升趋势,亮度L^*值、TBA值和组织形态评分呈下降趋势,色泽评分则表现为先上升后下降趋势。和热风干燥相比,远红外辅助热风干燥秋刀鱼片在色泽、质构特性方面的品质较好,组织形态、气味等方面的感官评分较高,但在TBA值方面两种干燥方式没有表现出显著性差异(P>0.05)。

Effects of Far-infrared Assisted Hot Air Drying on the Drying Characteristics and Quality of Saury Fillets

In order to investigate the influence of far-infrared assisted hot air drying on the drying characteristics and quality of saury fillets,the far-infrared assisted hot air drying and hot air drying processes were used to dehydrate saury fillets at 50,60,70,80 and 90 ℃,and the quality changes were observed. The results showed that in order to reduce the dry base moisture content of saury fillets to below 43%,the drying time required for hot air drying at 50 to 90 ℃ was 570,435,282,225 and 208 min,respectively,and the time required for far-infrared assisted hot air drying was 510,395,258,204 and 186 min. Increasing the drying temperature was beneficial to shorten the drying time and increase the drying rate,and the far-infrared assisted hot air drying had obvious drying advantages. Low-field nuclear magnetic resonance test results showed that the hard-to-flow water in the saury fillets was converted into free water and diffused outwards to achieve the purpose of drying. In terms of drying quality,the a* values and b* values of saury fillets increased to 4.85~8.98 and 12.08~16.01 respectively after drying. With the increase of drying temperature,texture indexes such as hardness,chewability and recovery,and the sensory score of umami,odor and chewability showed an upward trend,the L* value,TBA value and sensory score of tissue morphology showed a downward trend,while the color scores showed an upward trend and then a downward trend. Compared with hot air drying,far-infrared assisted hot air drying saury fillets had better quality in color and texture characteristics,and higher sensory scores in tissue morphology and odor,but there was no significance difference between two drying methods in TBA value(P>0.05).