凤尾茶精油提取工艺及凉茶饮料配方的优化

Orthogonal test design for optimization of extraction process of Elsholtzia bodinieri Vaniot oil and formula of herbal tea beverage

以云南凤尾茶为主要原料研制凉茶饮料,确定原料提取的最佳工艺条件及凉茶饮料的最优配方。通过采用L9(34)正交设计试验,以精油提取率为指标确定精油提取的最佳工艺参数,以凉茶饮料的感官评分值为指标考察饮料的最佳配方。结果表明,云南凤尾茶精油提取的最佳工艺条件为料液比1∶16 (g∶mL)、浸泡时间2 h、提取时间8 h、芳香水流速0.7 mL/min,精油提取率为0.60%;凉茶饮料的最优配方为:白砂糖55 g/L,凤尾茶浓缩液15 g/L,柠檬酸3 g/L,精油5 g/L。稳定剂用量为黄原胶0.4 g/L、羧甲基纤维素钠0.8 g/L时,稳定性最好,饮料沉淀率为6.3%。凉茶饮料可溶性固形物含量高于5.6%,总酸(以柠檬酸计)0.28 g/kg,微生物指标合格。该结果为凤尾茶精油的研究提供理论基础,也为开拓凤尾茶相关产品提供参考。

Herbal tea beverage was developed with Elsholtzia bodinieri Vaniot as raw material, with the most favorable extraction conditions and the optimal formula of herbal tea beverage explored and determined in this study. By L9(34) orthogonal test design method, the most favorable technical parameters for essence oil extraction were determined with extraction rate as the index and the optimal formula of the herbal tea beverage was determined with sensory score as the index. The results showed that the most favorable extraction conditions of E. bodinieri essence oil were: solid-liquid ratio of 1∶16 g/mL, soaking time for 2 h, distillation for 8 h, and aromatic water flow rate of 0.7 mL/min for an extraction rate of 0.60%;while the optimal formula of the herbal tea beverage was: sugar 55 g/L, E. bodinieri juice 15 g/L, citric acid 3 g/L, essence oil 5 g/L. The best stability was achieved with 0.4 g/L xanthan gum and 0.8 g/L CMC-Na used as stabilizers, when the precipitation rate was 6.3%. Such herbal tea beverage featured soluble solids content above 5.6%, total acid(in citric acid) of 0.28 g/kg and compliance in microbial indicators. These results would provide a theoretical basis for research on E. bodinieri oil, as well as a reference for product development based on E. bodinieri.