| Setaria italica.is resistant to drought,easy to grow,and foxtail millet has the characteristics of medicine and food homology,getting more and more popular in human life.Foxtail millet’s nutritional quality influences the taste quality of millet.For example,the starch content and amylose content of millet affect the gelatinization characteristics and texture characteristics of millet.Volatile flavor substances in millet affect the flavor characteristics of cooked millet.The expression and diversity of Setaria italica Waxy gene affect the synthesis of amylose in millet.In this experiment,JG21 and its derivates were used as the main materials.At the same time,the famous varieties YG01,ZZ05 and ZZ10 were added to determine the content of main components in millet and analyze its taste quality.Finally,Analysis the Polymorphism and Protein Structure of starch synthase gene in tested different Setaria italica.Varieties.The main results are as follows:1.Based on the absorption spectra of different reactions of amylose and amylopectin with iodine,determine the determination wavelength/reference wavelength of amylose and amylopectin is 620/453nm and 538/742nm,determined the regression equation and calculated the content of amylose and amylopectin starch in foxtail millet.The results showed that there was a good linear relationship at a certain concentration(amylose of 0-30 ug/mL,amylopectinof 0-150 ug/mL,),2.The gelatinization characteristics of millet flour and millet starch of each variety were measured with a rapid viscosity analyzer.The texture characteristics of millet porridge were determined by a physical property analyzer and correlated with the content of millet components.The main results are as follows:(1)There was an extremely significant positive correlation between the gelatinization characteristics of millet flour and millet starch,and the correlation coefficient was very high,indicating that the gelatinization characteristics of millet flour can be used to characterize the pasting characteristics of foxtail millet.(2)Among all the characteristic values of gelatinization characteristics of foxtail millet,the millet variety can be identified and the pasting characteristics of millet can be effectively judged by the Breakdown and the Setback,The higher the Setback,the smaller the Breakdown,the greater the Consistence,the longer the Peak Time,and the higher the Pasting Temperature.The better the millet’s thermal stability,the harder it is to gelatinize(3)The water content was positively correlated with the RVA characteristic value,the amylose content was positively correlated with the Consistence,and negatively correlated with other RVA values.The crude fat content was positively correlated with the Breakdown and Consistence,and negatively correlated with the Pasting Temperature and Time.(4)In the study of the texture characteristics of cooked foxtail millet,Adhesiveness has a certain effect on the identification of cooked millet.The water content and crude fat content were negatively correlated with the texture characteristics of cooked millet..The content amylose was positively correlated with the Hardness,Adhesiveness,Gumminess,Chewiness and Resilience of cooked millet,negatively correlated with the Springiness and Cohesiveness of cooked millet.(5)Gelatinization characteristics Breakdown of millet can be used to predict the texture characteristics of cooked millet,to some extent.The Breakdown of millet is negatively correlated with the texture characteristics of cooked millet.The texture characteristics of cooked millet are negatively correlated with the Final Viscosity of pasting of millet.Springiness was negatively correlated with Final Viscosity,positively correlated with Breakdown,but the correlation coefficient was low and correlation was not obvious.3.Headspace solid-phase microextraction(HS-SPME)combined with gas chromatography-mass spectrometry(GC-MS)was used to determine volatile flavor compounds in millet.The main results are as follows:(1)A total of 60 volatile substances were identified,including 20 kinds of aldehydes,7 kinds of ketones,6 kinds of alcohols,2 kinds of phenols,3 kinds of acids,4 kinds of benzene derivatives,and 6 kinds of hydrocarbons,8 kinds of esters and 3 kinds of other compounds.Identified Pentanal、5-heptyldihydro-2(3H)-Furanone、1-Pentanol、and 3-Methyl-3-octanol firstly.(2)Aldehydes and hydrocarbons constitute the main volatile components in millet porridge,and aldehydes are the main source of millet gruel.(3)Quantitative analysis of the main components of millet gruel flavour,found that the the hexanal content is highest..5.The bioinformatics analysis of the Waxy gene of each tested Setaria italica based on the second generation sequencing results,the specific results are as follows:(1)There are two copies of the Waxy gene in Setaria italica,SiWaxy1 and Si Waxy2,located on chromosomes 4 and 2,respectively.(2)Analyzed Waxy genediversity and predicted the encoded protein based on the SNP and INDel.Find that Woaxy gene in Setaria italica encoded three Waxy proteins,as SiWaxy1,Si Waxy1b and SiWaxy2.These protein belongs to the glycosyltransferase superfamily.(3)The phylogenetic analysis showed that the protein domain encoded by Waxy was conserved,and the Waxy gene of Setaria italica had similar homologous sequences with other nine kinds of plants,and the genetic relationship was more advanced.In summary,the material components of foxtail millet,such as moisture,total starch,crude fat,and amylose content,affect the gelatinization characteristics,texture characteristics,and flavor characteristics of millet.Aldehydes are the main source of millet aroma.Setaria italica Waxy gene has high homology with Waxy genes in other plants,and the protein domain encoded by Waxy gene is highly conserved.This study can provide some theoretical data for the identification and improvement of millet quality,and provide reference and theoretical basis for the cultivation of high-quality,high-yielding millet varieties. |
PDF Full Text Request