Relationship Between Amino Acids,Polyphenols And Fatty Acids And Tobacco Quality Of Yibin Flue-cured Tobacco

To analyze the relationship between Yibin tobacco leaves quality and the chemical components of aroma precursors,such as free amino acids,polyphenols,fatty acids,pectin and cellulose,this paper analyzed the external quality evaluation and internal quality evaluation of Yibin tobacco,and detected the contents of free amino acids,polyphenols,fatty acids,pectin and cellulose in the tobacco leaves Orthogonal partial least squares(OPLS)was used to reveal the relationship between these chemical components and tobacco quality.The main conclusions are as follows:(1)In Yibin flue-cured tobacco,amino acids in the flue-cured tobacco leaves is less and the difference of different free amino acids is more obvious.17 kinds of amino acids were detected,among which proline content is the largest,ranging from 5400.1-11088.3mg/kg,followed by phenylalanine,glycine and cystine.Most of the free amino acids were more closely related to the quality of flue-cured tobacco.There was a negative correlation between arginine and tobacco quality,and there was a close relationship between aspartic acid and proline and the inner quality of flue-cured tobacco.In addition,amino acids such as arginine and threonine are related to the color,chroma and identity of flue-cured tobacco leaves(2)General situation of polyphenol content in Yibin flue-cured tobacco:rutin content is the most,followed by anisodamine Pavilion content.The total content of polyphenol in flue-cured tobacco is higher,quercetin and kaempferol content is lower.Chlorogenic acid and rutin are closely related to the appearance quality,and negatively related to the color and chroma of flue-cured tobacco leaves;caffeic acid is negatively related to tobacco leaves;chlorogenic acid,rutin,quercetin and caffeic acid are closely related to the internal quality of tobacco leaves.(3)The content of linoleic acid is the highest in Yibin flue-cured tobacco,followed by pentadecane monoenoic acid.The content of fatty acid in flue-cured tobacco varies greatly,and the total content is more.It is closely related to the appearance quality:palmitoleic acid,nutmeg oleic acid,undecanoic acid,erucic acid and ?-linolenic acid,which have a significant positive correlation with the appearance score of flue-cured tobacco;it is closely related to the internal quality of flue-cured tobacco:eicosapentaenoic acid and 24 carbon enoic acid,which have a significant positive correlation with the internal quality of flue-cured tobacco.The unsaturated fatty acids such as palmitoleic acid,?-linolenic acid and 24 carbonic acid had significant negative correlation.(4)The average content of pectin in Yibin flue-cured tobacco was 36.2g/kg,and the difference of cellulose among different samples was small.Pectin has a positive correlation with the appearance quality of flue-cured tobacco and a negative correlation with the internal quality of flue-cured tobacco.Cellulose has little effect on the quality of flue-cured tobacco.