The Quality Analysis And Anthocyanins Composition Research Of Main Cultivated Varieties Sweet Potato In Shaanxi

Sweet potato(Ipomoea batatas Lam.)belongs to Convolvulaceae,an annual or perennial herbaceous plant.It not only contains starch,dietary fiber,fat,various mineral elements but also riches in anthocyanins,ascorbic acid,Vitamin B and some other nutrients.It has a broad development space for the characteristics of drought resistance,barren resistance,easier cultivation,high and stable output,high adaptability,and high nutrition.Basing on the present existing research situation and problems of sweet potato resources in Shaanxi province,this paper uses 16 main cultivars of sweet potato in Shaanxi Province as experimental materials and carries out the research work of "The Quality Analysis and Research on Anthocyanins Composition of main sweet potato varieties in Shaanxi".The main researches and results are as follows:(1)Research of sweet potatoes' eating quality and nutritional composition:This part of research mainly refers to some related food security national standards and uses ultraviolet-visible spectrophotometric method to analysis the moisture contents,total sugar,deoxidize sugar,starch,fat,anthocyanins,flavonoids,ascorbic acid,protein and other essential nutrients and functional ingredients from varieties sweet potato,which mainly cultivated in Shaanxi.The results show that the tested potatoes are rich in nutrients,the moisture contents in fresh potatoes are 58.52±0.01%to 73.26±0.01%,ascorbic acid contents are 26.1362±0.0050 ?g/g to 94.8718±0.0028 pg/g.The total sugar contents are 27.580±0.002 mg/g to 33.303±0.002 mg/g,deoxidize sugar contents are 6.56±0.12 mg/g to 18.82±0.14 mg/g,starch contents are 31.13±0.03 mg/g to 69.86±0.05 mg/g,crude fat contents are 1.83±0.02%to 2.88±0.04%;anthocyanins contents are 0.0987±0.0030 mg/g to 4.5853±0.0030 mg/g,total flavones contents are 1.872±0.025 mg/g to 19.037±0.025 mg/g and protein contents are 1.95±0.01%to 2.20±0.02%.(2)Research of vitamin B in different varieties of sweet potatoesThis part of research mainly uses the ultraviolet-visible spectrophotometric method,the standard curve method and takes VB1,VB2 and VB12 as standard samples to make qualitative analysis and quantitative research of vitamin B in 16 kinds of sweet potatoes.The results show that the pretreatment method is simple,the analysis method is accurate and reproducible.Different varieties of sweet potatoes in Shanxi province are rich in vitamin B,the contents of vitamin B1,vitamin B2 and vitamin B12 in sweet potatoes are:2.2857±0.002 mg/g to 7.9033±0.002 mg/g,1.0043±0.003 mg/g to 3.1492±0.003 mg/g,1.1820±0.001 mg/g to 6.0494±0.002 mg/g.The contents of vitamin B is related to the varieties of sweet potatoes and vitamin B.(3)Research of mineral element in different varieties of sweet potatoesThis part of research mainly uses wet digestion-atomic absorption spectrometric method to detect the contents of Zn,Fe,Cu,Mg,Mn and heavy metals(Ni,Cr,Cd,Hg,Pb)from 16 kinds of sweet potato and soil samples from Yangling and Hanzhoung,which are the main cultivation area of sweet potato in Shaanxi Province.The results show that the digestion is complete,reagent consumption is less,pollution is lower;the tested sweet potato samples and soil samples are rich in content of mineral elements.The contents of mineral elements in sweet potatoes are correlated positively to the contents of mineral elements in soil.The contents of heavy metals(Ni,Pb,Cd,Hg,Cr)in sweet potato samples from two tested places are consistent with the GB2762-2012 food safety and limitation standards.(4)Qualitative analysis of anthocyanins compositions in different varieties of purple sweet potatoesThis part of research mainly uses UPLC-MS/MS method,takes 7 kinds of purple sweet potatoes as the experiment material,8 kinds of anthocyanins as standard,combining with Liquid chromatography-mass spectrometry technology in the positive ion source(ESI)and multi-reactions monitoring(MRM)technology to make systematic qualitative analysis of anthocyanins' composition in this 7 kinds of purple sweet potatoes.The results show that the method is accurate,fast and selective.Cy-3-glu is detected in the tested 7 kinds of purple sweet potatoes,except Qin Zi 1.Petunidin has been founded in other six kinds purple sweet potatoes.Mv-3-glu has been founded in 5 kinds of purple sweet potatoes,except Hua Zi and Qin Zi 1.It can be seen that anthocyanins composition in the tested purple sweet potatoes are mainly cyanidin-3-glucoside(Cy-3-glu),petunidin and malvidin-3-glucoside(Mv-3-glu).Cy-3,5-diglu is tested in Qin Hei 1 and delphinidin is tested in Qin Zi 1.