A Comparative Study On The Content Of Methoxypyrazine In Different Grape Varieties And Wines

In order to explore the difference of methoxypyrazine content in different grape varieties and wines at the eastern foot of HeLan Mountain,the 6-year-old 'Pinot Noir','Marselan','Petit Verdo','Cabernet Sauvignon','Malbec','Merlot' and 'Chardonnay' were used as test materials.The fruit quality,the content of 6 kinds of methoxypyrazine and the expression of methoxypyrazine transferase related genes in grape fruit and wine were determined during grape development.The results showed that:(1)The hundred-grain weight of 'Malbec' was significantly higher than that of other varieties(235.34 g),the soluble solids content of 'Petit Verdo' was 25.26° Brix,the titratable acid content of 'Chardonnay' was 7.71 g/L,the total phenol content of 'Pinot Noir'was 8.01 mg/g,respectively,and the anthocyanin content of 'Petit Verdo' was 7.41mg/g.(2)Three methoxypyrazines(MOMP,MEMP,ETMP)were not detected in the berries of different varieties during the harvest period,and the contents of IPMP,SBMP and IBMP were significantly different The highest content of IPMP was 2.374 ng/L in the fruits of Marselan,followed by 'Cabernet Sauvignon',1.555 ng/L.The highest content of SBMP was 4.708 ng/L in the berries of Pinot Noir,and the lowest was 2.544 ng/L in the fruits of 'Marselan'.The highest content of IBMP was 2.544 ng/L in the fruits of 'Marselan',11.852 ng/L,'Cabernet Sauvignon' is the lowest,6.023 ng/L.(3)The content of SBMP and IBMP in 'Cabernet Sauvignon' wine was the highest(10.662 ng/L),'Pinot Noir' wine was the lowest(2.383 ng/L).The content of IBMP in 'Chardonnay' wine was the highest(19.313 ng/L),'Malbec' wine was the lowest(5.354 ng/L),and the content of SBMP and IBMP in grape wine was higher than that in grape fruit at harvest.(4)The activity of VvOMT1 to IBMP of all wine grape varieties was higher than that of IPMP.In conclusion,the fruit quality of 'Marselan' is better than that of other red varieties.Choosing the right grape varieties is beneficial to improve the quality of wine.The metabolism of methoxypyrazine needs further study.