摘要
为明确不同干燥方法对黄秋葵品质的影响,优选其干燥技术,以新鲜黄秋葵果实为原料,分别采用热风、冷冻、微波、自然干燥方法干制,测定不同干制方法得到的黄秋葵干果中膳食纤维、果胶、黄酮等物质的含量,评价不同干制方法所得果实的抗氧化能力。结果表明:干燥方法并不影响黄秋葵中总膳食纤维、总糖、总氮和灰分的含量。可溶性膳食纤维、果胶、黄酮与Vc含量均以冷冻干燥果实最高,依次为14.21%、7.38%、1.72%和322.7 mg/kg,与新鲜果实中含量均无显著性差异(P>0.05);不同方法干制后黄秋葵中总酚含量降低。自然干燥的黄秋葵总还原力(FRAP值)最低为0.767 mmol/L,而其他干制样品与新鲜黄秋葵的总还原力(0.856 mmol/L)相近且无显著性差异(P>0.05);冷冻干燥及新鲜果实对1,1-二苯基-2-三硝基苯肼(DPPH)自由基、羟自由基(·OH)的清除率较高,但新鲜果实对超氧阴离子(O-2·)的清除率则均高于干制后的黄秋葵。综合分析认为,冷冻干燥能较好保持新鲜黄秋葵的营养成分和抗氧化能力,可作为黄秋葵即食加工的首选方法;自然干燥成本低,处理量大,所得干果中果胶含量高,适用于食品精深加工用黄秋葵的干制处理。
In order to research the effects of drying methods on the quality of fresh okra,the drying process was optimized. The dietary fiber,pectin and flavonoid were determined in different drying methods,including hot-air drying（ HD）,freeze drying（ FD）,microwave drying（ MD） and natural drying（ ND）. The nutrition and antioxidant capacity of okra fruits were then evaluated. The results showed that total dietary fiber,sugar,protein and ash contents were not affected by the drying methods. Among four drying methods,the FD has the highest soluble dietary fiber（ 14. 21%）,pectin（ 7. 38%）,flavonoid（ 1. 72%） and Vc（ 322. 7 mg /kg） content,it had no significant difference with fresh okra fruits（ P 0. 05）. The total phenol content of okra fruits were decreased after drying in all four methods. The total reducing capacity of okra fruits dehydrated by ND was the lowest（ 0. 767 mmol / L）,but other drying methods were almost the same as fresh okra（ 0. 856 mmol / L）. For the scavenging capacities against DPPH and·OH,FD sample and fresh fruits were better than other frying methods. However,the scavenging capacity against O-2· of fresh okra was significantly higher than any other drying method. Therefore,freeze drying method,which could retain the nutrition and antioxidant capacity of fresh okra,should be the primary processing method in ready-toeat okra food processing. Air drying method has the advantages on low cost,large processing load,and higher pectin content,and can be used in drying of further processing of dehydrated okra products.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2016年第5期120-125,共6页
Food and Fermentation Industries
基金
泰安市大学生科技创新行动计划(No.2014D012)资助
关键词
黄秋葵
干燥方法
膳食纤维
果胶
黄酮
总酚
抗氧化能力
okra
drying method
dietary fiber
pectin
flavonoid
total phenol
antioxidant capacity
