摘要
Abstract
To explore the effects of different blanching methods on the freeze-drying quality and volatile flavor compounds of daylily before drying,the daylily was blanched with hot water at 90℃and atmospheric steam for 60 s,and explored the effects of 30,60 and 90 s superheated steam blanching(110-140℃)on the freeze-drying rate,nutrient composition,color and microstructure of Ningxia"Da Wu-zui"daylily.Headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS)was used to qualitatively analyze the changes in the types and contents of volatile flavor compounds in daylily under different blanching methods.Results showed that the freeze-drying of dayli-ly was faster,and the nutrients of daylily were more retained after 30 seconds,with soluble protein of 11.84 g/100 g,vitamin C of 46.13 mg/100 g,total sugar of 36.02 mg/g and flavonoids of 1.48 mg/g.The L∗ value was 67.56,the a∗ value was-1.95,the b∗value was 30.54,the color was close to fresh daylily,and the cross-sectional holes were cleaned considerably and evenly distributed.The retention of volatile flavor compounds in daylily was significantly higher than hot bleaching.The retention of volatile flavor compounds in daylily by hot water blanching was the least,possibly due to the dissolution and loss of water-soluble volatile flavor compounds in water.Based on the above,30 s superheated steam blanching can be selected as one of the pretreatment methods for Ningxia fresh daylily,and HS-GC-IMS can qualitatively analyze the types and contents of volatile flavor compounds in daylily,which provides strong technical sup-port for the detection of volatile flavor compounds in a daylily.关键词
黄花菜/烫漂/过热蒸汽/风味物质/顶空-气相色谱-离子迁移谱Key words
Hemerocallis citrina Braoni/blanching/superheated steam/flavor substances/headspace-gas chromatography-ion mobility spectrometry
