Study On Preparation And Quality Evaluation Of Instant Tartary Buckwheat Tea

Tartary buckwheat belongs to the genus Buckwheat of the Dicotyledonaceae family.It is a rare dual-purpose crop that can be used as medicine or edible on the earth.Tea with high nutritional value like Tartary buckwheat tea and health care tea are more and more popular.At present,the common Tartary buckwheat tea is mainly whole plant tea and granulated tea.The main drinking method of Tartary buckwheat tea is brewing,but with the acceleration of people's life rhythm and improvement of living standards,while the fine tea drinking culture is recognized by the public,while the convenience is also required.The development of instant products is necessary.Therefore,this study takes Tartary buckwheat tea as the research object,and conducting preliminary exploration on the extraction,drying and other processing techniques to prepare an instant tartary buckwheat tea product.And adopting various analyses such as GC-MS,UPLC-Q-TOF-MS,etc.to compare the aroma components and antioxidant activity of the prepared instant tartary buckwheat tea with the tea powder of common commercial tartary buckwheat tea as a control group.The goal is to identify the polyphenols contained in it to indicate the experiment practicability of making instant tartary buckwheat tea powder.The specific research results are as follows:A single factor experiment combined with response surface optimization conditions was used to optimize the extraction process with the total flavonoids in the extraction liquid as indicators.The results showed that under the conditions of leaching temperature 83?C,leaching time 130 min,material-liquid ratio 1:10,and the best leaching scheme is obtained.The predicted value of the total flavonoid content the extract of Tartary buckwheat is 3.20%,and the measured value is 3.14%.The calculated relative error is only 1.91%,which is not much different from the predicted value.Therefore,the model obtained in this experiment can be used to simulate the actual extraction of Tartary buckwheat tea,and the obtained extraction conditions can be applied in practice.Compare the effects of spray drying and vacuum drying,and add different proportions of drying excipients to observe the impact on the product's preparation,fluidity,moisture content,powder collection rate and sensory quality to choose the best drying conditions.The results show that with the increase in the amount of maltodextrin added,all indicators of the tested products are developing in the direction of optimization.When the turning point is reached,the changes start to develop slowly or in the opposite direction.Comprehensive consideration shows that when the amount of dry excipients reaches 40%,the effect is the best.According to the drying process of instant tartary buckwheat tea powder and the analysis of various properties of the powder,the processing technology of instant tartary buckwheat tea powder prepared by vacuum drying processing method is superior.Using solid-phase microextraction combined with GC-MS analysis technology to analyze and determine the volatile flavor of different Tartary buckwheat tea samples.In the analysis and detection process,a total of 108 compounds were identified,including 15 alcohol compounds,10 aldehyde compounds,8 ketone compounds,12 ester compounds,32 alkane compounds,and 9 olefin compounds.Species,3 phenolic compounds,3 acid compounds,16 heterocyclic and other compounds.The most abundant substances in the tartary buckwheat tea samples are aldehyde compounds and alkane compounds.The comparison shows that the instant tartary buckwheat tea powder prepared by the experiment can well retain the volatile aroma components.Taking Tartary buckwheat tea powder as the research object,the strength of antioxidant activity was judged based on the content of total flavonoids and total polyphenols and the correlation with DPPH free and economic scavenging ability.The total flavonoid content of Tartary buckwheat instant tea powder was 2.1788 mg GAE/g,and the total polyphenol content was 4.1928 mg RE/g,and the Instant tartary buckwheat tea powder has strong antioxidant capacity.At the same time,UPLC-Q-TOF-MS was used to qualitatively analyze the polyphenol composition of instant tartary buckwheat tea powder,and rutin,quercetin,protocatechuic acid,begulin,hyperin,Quercetin-malonyl glucoside,quercetin-3-O-rutinoside have all been proved in other studies that the flavonoid-based substances obtained in tartary buckwheat tea show that the experimental preparation The instant Tartary buckwheat tea powder can effectively retain the active ingredients.