茶树花真空冷冻干燥工艺优化及体外抗氧化活性  

Study on Vacuum Freeze⁃Drying ProcessTechnology and in vitro Antioxidant Activity of Tea Flowers

作　　者：陈美链 李杨 刘淑燕[2] 李金贵 胡汉亮 郭泽镔[2] CHEN Meilian;LI Yang;LIU Shuyan;LI Jingui;HU Hanliang;GUO Zebin(College of Tea and Food Science and Technology,Zhangzhou College of Science&Technology,Zhangzhou 363202,Fujian,China;College of Food Science,Fujian Agriculture and Forestry University,Fuzhou 350002,Fujian,China;Zhangzhou Tiankang Detection Technology Co.,Ltd.,Zhangzhou 363202,Fujian,China;Zhangzhou Snack Food Industry Technology Research Institute,Zhangzhou 363202,Fujian,China)

机构地区：[1]漳州科技职业学院茶与食品科技学院,福建漳州363202 [2]福建农林大学食品科学学院,福建福州350002 [3]漳州天康检测技术有限公司,福建漳州363202 [4]漳州市休闲食品产业技术研究院,福建漳州363202

出　　处：《食品研究与开发》2024年第18期169-180,共12页Food Research and Development

基　　金：福建省科技厅星火项目(2021S0051)。

摘　　要：为探究茶树花真空冷冻干燥最佳工艺并对冻干茶树花的体外抗氧化活性进行研究,以福鼎大白茶茶树花为研究对象,考察不同因素(预冻温度、预冻时间、真空度、搁板最大加热温度)对茶树花感官评分和复水比的影响,并通过响应面优化得到最佳工艺条件:预冻温度-30℃、预冻时间3.5 h、搁板最大加热温度39℃,在此条件下,福鼎大白茶冻干茶树花的感官评分为88.57±1.24,复水比为3.26±0.14。对比冻干前后茶树花生物活性成分和感官指标得出,真空冷冻干燥技术能够较好地保留茶树花的外观形态和活性成分。对冻干茶树花进行体外抗氧化活性研究,结果表明,茶树花羟自由基清除率明显高于同浓度的VC,DPPH自由基清除率和还原能力低于同浓度的VC,冻干茶树花DPPH自由基清除率和羟自由基清除率的IC50分别为78.85µg/mL、0.55 mg/mL,表明茶树花具有较好的抗氧化活性。In order to ascertain the optimal vacuum freeze⁃drying technology of tea flowers and study the in vi‐tro antioxidant activity of freeze⁃dried tea flowers,the flower of Fuding big white tea was taken as the research object,and the effects of different factors(pre⁃freezing temperature,pre⁃freezing time,vacuum degree,and maximum heating temperature of shelf)on the sensory score and rehydration ratio of the tea flower were exam⁃ined.The optimal conditions were obtained through response surface optimization as follows:pre⁃freezing tem⁃perature of−30℃,pre⁃freezing time of 3.5 h,and maximum heating temperature of shelf of 39℃.Under these conditions,the sensory score of the freeze⁃dried flower of Fuding big white tea was 88.57±1.24,and the rehy⁃dration ratio was 3.26±0.14.The bioactive constituents and sensory indexes of the tea flower before and after freeze⁃drying were compared,and it was concluded that vacuum freeze⁃drying technology could better preserve the appearance and active constituents of the tea flower.Through research on the in vitro antioxidant activity of the freeze⁃dried tea flower,the result showed that the scavenging rate of hydroxyl radicals in the tea flower was significantly higher than VC at the same concentration,while the scavenging rate and reducing capacity of DPPH radicals were lower than that of VC at the same concentration.The IC50 for the scavenging rates of DPPH radicals and hydroxyl radicals in the freeze⁃dried tea flower were 78.85µg/mL and 0.55 mg/mL,respectively,indicating that the tea flower had good antioxidant activity.

关 键 词：茶树花 真空冷冻干燥 感官评分 生物活性成分 抗氧化活性 

分 类 号：TS205[轻工技术与工程—食品科学]