提高冻干香葱品质的工艺研究

为保持真空冷冻干燥香葱的鲜绿、天然的葱香味及品质,采用漂烫和护色剂对香葱进行浸泡护色处理,固相微萃取气质联用(SPME-GC-MS)测定香葱的挥发性成分,并确定真空冷冻干燥香葱气味最浓郁时的干燥时间、温度和真空度。实验表明:SPME-GC-MS分析确定以硫代亚磺酸酯的含量来衡量干燥后香葱气味的浓郁程度。干燥香葱颜色最鲜亮时的条件为:100℃水中烫漂30s,0.3%碳酸钠碱液中浸泡10min,0.03%氯化锌和0.2%氯化钙护绿液中护色30min。满足香葱香味最浓郁及水分要求的条件为:0℃下升华干燥6h,25℃下解析干燥2h,真空度60Pa。

Study on the technology of quality improvement of vacuum freeze-drying chive

In order to maintain crude green,adour and quality of freeze-drying chive,blanching and green-maintaining regents were used for green-maintaining of chive.SPME-GC-MS was used to detect the volatile compounds of chives.And the best drying time,temperature and vacuum were determined while the flavor of freeze-dried chive was the strongest.The test showed that the content of the thiosulfinates was comfirmed to evaluate the level of chive odour with the result of SPME-GC-MS.The best condition of maintaining chive green was that chives were blanched 30s at 100℃,soaked 10 minutes in 0.3% Sodium carbonatem,and soaked 30 minutes in 0.03% zine chloride and 0.2% calcium chloride.And the chive adour was the strongest and the water content met requirements when the time of sublimation drying at 0℃ for 6h,analytical drying at 25℃ for 2h and the vacuum degree was 60Pa.