The Leaf Quality Evaluation Of Fagopyrum Megaspartanium Germplasm Resources And The Development Of Its Leaf Tea Product With Rich GABA

The nutrition quality and healthcare compoment contents inleaves of133plants of48accessions of F.megaspartanium werestudied under the same cultivated conditions. SomeF.megaspartanium accessions with high contents of both flavone andgamma-aminobutyric acid (GABA) were discovered for developing newvarieties. Meanwhile,the commercial technics for F.megaspartaniumleaf fermented tea were also studied on the basis of leaves of highflavone and high GABA F.megaspartanium accession. The changes oftea quality among different growth periods and the qualitycomparison between F.megaspartanium leaf fermented tea and otherkinds of tea product were also studied. The main results were asfollows:1.Variation of flavones and GABA contents in F.megaspartaniumleaves: Under the same cultivated circumstances,there are greatvariation among different accessions and among different plants.For F.megaspartanium,the average flavones content of leaves is8.96%with the range of7.51～10.61%, the average GABA content ofleaves is0.101%with the range of0.069～0.184%.There are higherflavones content and the GABA content of leaves of the accessionnative to Guizhou and Hubei. Among them, M1plant native toGuiyang,Guizhou is the highest, up to the flavones content of10.16% and the GABA content of0.184%. As a high quality raw material ofleaf fermented tea with rich GABA,it can be applied to the researchand development of buckwheat products.2.Variation of glutathione,Ascorbic acid,dietary fiber,soluble protein and soluble sugar contents of leaves ofF.megaspartanium:The average glutathione content of leaves ofF.megaspartanium plants among different accessions is0.305mg/gwith the range of0.247～0.351mg/g. There is a significantdifference of the glutathione content of F.megaspartanium leavesamong different regions. Among them, the accession (M2) native toGuiyang,Guizhou has the highest up to0.351mg/g, and the accession(M10-10) native to Shizhu,Chongqing the lowest (only0.247mg/g).The average Ascorbic acid content of leaves of F.megaspartaniumamong different accessions is0.074mg/g with the range of0.071～0.079mg/g. There is no significant difference among differentregions. Among them, the accession (M1-2) native to Guiyang,Guizhouhas the highest up to0.079mg/g, and the accession (M3-7) nativeto Xingren,Guizhou the lowest (only0.0711mg/g). There is nosignificant difference of the dietary fiber content among differentregions. The average dietary fiber content of leaves ofF.megaspartanium of different accessions is50.13%with the rangeof42.15～60.77%. Among them, the accession (M1) native to Guiyang,Guizhou is the highest dietary fiber content up to60.77%,and the accession (M10-5) native to Baojing,Hunan the lowest (only42.15%). The average insoluble dietary fiber content of leaves ofF.megaspartanium among different accessions is42.19%with therange of35.11～49.88%. The insoluble dietary fiber content ofleaves of the accession (M8-4) native to Huaxi,Guizhou is thehighest up to49.88%, and the accession (M4-2) native to Kangding,Sichuan is the lowest,only35.11%. The average soluble dietaryfiber content of leaves of F.megaspartanium of different accessionsis7.933%with the range of3.04～13.32%. Among them, the accession(M4-2) native to Huaxi,Guizhou is the highest up to13.32%, and theaccession (M10-10) native to Shizhu,Chongqing is the lowest,only3.04%. There is a significant difference of the soluble proteincontent and soluble sugar content of leaves of F.megaspartaniumamong different regions. The average soluble protein content ofleaves of F.megaspartanium among different accessions is25.196mg/g with the range of17.3～35.1mg/g. Among them, theaccession (M4-1) native to Kangding,Sichuan is the highest up to35.1mg/g,and the accession (M3-7) native to Xingren,Guizhou is thelowest,only17.3mg/g. The average soluble sugar content of leavesof F.megaspartanium among different accessions is13.506%with therange of9.22～17.9%. The soluble sugar content of leaves of the accession (M5-2) native to Yvlonggou,Sichuan is the highest up to17.9%,and the accession (M8-4) native to Huaxi,Guizhou is thelowest,only9.22%.3.The correlation analysis among parameters on leaves of F.magaspartanium: there are the significant positive relationshipsbetween GABA content and flavones, glutathione,and soluble dietaryfiber contents (r1,2=0.718**，r1,3=0.420*，r1,7=0.595**). There are thesignificant positive relationships between flavone content andglutathione content (r2,3=0.448*), between total dietary fiber andinsoluble dietary fiber contents (r5,6=0.853**), and between Ascorbicacid content and soluble protein content (r4,8=0.404*), and thesignificant negative relationships between soluble sugar contentand insoluble dietary fiber content (r9,6=-0.394*). There are nosignificant relationships as for other parameter combinations.4.The test of growth period: The quality analysis on the leavesof F.megaspartanium in different growth period found that there isa significant difference of the nutrition quality and healthcarecompoment contents in the leaves of F.megaspartanium plants amongdifferent growth period. Among them, the beginning of floweringstage is the optimal growth period when the flavones content andthe GABA content in leaves are the highest. 5.The fermentation process of F.megaspartanium leaf tea: Theoptimal conditions of F.megaspartanium leaf fermented tea are watercontent of65%in withering leaves, rolling for90min, fermentingat30℃for29h. Under these conditions, the F.megaspartanium leaffermented tea has the best quality such as strip rope tight volume,color zeu-run, orange and bright soup, and mellow taste and it’sthe comprehensive quality is higher than the F.megaspartanium leafgreen tea.6.Comparative analysis of quality of F.megaspartanium leaffermented tea to other kinds of tea product: Determination resultsof GABA,flavone,glutathione,soluble dietary fiber,soluble proteinand soluble sugar contents of Qimen black tea, Puer tea, DouYunmaojian tea, Whole-plant buckwheat tea, buckwheat seed tea,buckwheat embryo tea, and F.megaspartanium leaf fermented teashowed that there is a significant difference in the nutritionquality and the healthcare compoment contents among different kindsof tea. F.megaspartanium leaf fermented tea showed the highestflavone, GABA, soluble sugar and soluble dietary fiber contents inall tea samples.7.The correlation analysis among parameters ofF.megaspartanium leaf fermented tea: There are the significantpositive relationships between soluble sugar content and GABA content and glutathione content (r1,9=0.961*，r3,9=0.982*) and betweenAscorbic acid content and soluble dietary fiber content and solubleprotein content (r4,7=0.962*，r4，8=0.983*),and the significant negativerelationships between total dietary fiber content and Ascorbic acidcontent (r4,5=-0.970*) and between total dietary fiber content andsoluble dietary fiber content and soluble proteincontent(r5,7=-0.976*，r5,8=-0.953*). There are no significantrelationships as for other parameter combinations.8. The quality of F. megaspartanium leaf fermented tea wasevaluated completely. It is clear that GABA，flavone,solubledietary fiber, soluble suger,lysine,leucine and VitaminB5contentsof the leaf fermented tea were significantly higher than othercommon tea and buckwheat tea products.