不同干燥方式无花果干质构及挥发性成分比较

Comparison of texture quality and volatile components of dried figs by different drying methods

为了高效利用无花果资源,延长果品供应期,该研究将新鲜无花果经热风、真空、真空冷冻等方式干燥,采用电子眼、质构仪、气相色谱-质谱联用(GC-MS)等对3种不同干燥方式处理后的无花果干进行品质分析。结果表明,无花果干水分含量在5%左右时,3种干燥方式得到的无花果干能被电子眼有效区分;真空冷冻干燥耗时较久,耗时分别是热风干燥的2.75倍,真空干燥的3.14倍;经质构分析结果可知,热风干燥的无花果干硬度值为1 286. 41 g、脆性值1 074. 82 g、弹性0. 99 mm、凝聚力为0. 78%、咀嚼性为985. 36 mJ、回复性为0. 34 mm,均大于真空干燥和真空冷冻干燥无花果干;经挥发性成分分析结果可知,3种无花果干共检测出52种挥发性成分,主要有醛类、醇类、酸类、烃类,其占总挥发性成分的90.49%~91.26%。其中热风干燥果干检测出33种、真空干燥果干检测出32种、真空冷冻干燥果干检测出29种,3种果干共有成分为15种,主要挥发性成分为苯甲醛,含量分别为热风干燥38. 97%,真空干燥39. 03%,真空冷冻干燥46.49%。此外仅在热风干燥处理的无花果干中检测到补骨脂素。

In order to make efficient use of fig resources and extend the fruit supply period,the fresh figs were dried by hot air,vacuum and vacuum freezing in this study. The quality of the dried figs treated by three different drying methods was analyzed using electronic eye,texture analyzer and gas chromatography-mass spectrometry(GC-MS),etc. The results showed that the dried figs obtained by the three drying methods could be effectively distinguished using the electronic eye when their moisture content was about 5%;Vacuum freeze-drying took the longest time,which was 2. 75 times of hot air drying,and 3. 14 times of the vacuum drying. The texture analysis results showed that the hardness value of the dried figs obtained by hot air drying was 1 286. 41 g and the fracturability value was 1 074. 82 g,springiness value was 0. 99 mm,cohesiveness value was 0. 78 %,chewiness value was 985. 36 mJ,resilience value was 0. 34 mm,both greater than vacuum drying and vacuum freeze dried fig;The volatile component analysis results showed that totally 52 kinds of volatile components were detected in the three kinds of dried figs,mainly aldehydes,alcohols,acids,hydrocarbons,which accounted for 90. 49%-91. 26%of the total volatile components. Meanwhile,33 of them were detected in hot-dried dried figs,32 in vacuum dried figs,and 29 in vacuum freeze-dried dried figs. There were 15 kinds of common volatile components detected in all three dried figs. The major volatile components were benzaldehyde,which took part 38. 97% in hot air method,39. 03 % in vacuum dried method,and 46. 49 % in vacuum freezedried. Besides,psoralen was detected only in the dried figs of hot air drying.