Department of Wine Science and Waite Research Institute, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, South Australia 5064, Australia.
CSIRO Agriculture and Food, Waite Campus, Locked Bag No. 2, Glen Osmond, South Australia 5064, Australia.
J Agric Food Chem. 2022 May 4;70(17):5417-5426. doi: 10.1021/acs.jafc.1c07978. Epub 2022 Apr 20.
Ramsey rootstock has previously been implicated in an approximate 8-fold increase of 3-isobutyl-2-methoxypyrazine (IBMP) levels in the rachis (grape bunch stem) of L. cv. Shiraz scions over own-rooted Shiraz vines at harvest. IBMP extracted from rachis during red wine fermentation can contribute potent "green" flavors. Methoxypyrazines (MPs) are normally present in Cabernet Sauvignon grapes, rachis, and wines, but it is unknown whether rootstocks can influence the MP concentration in the rachis. This study considered the effect of eight rootstocks including Ramsey and own roots on the concentrations of IBMP, 3-isopropyl-2-methoxypyrazine (IPMP), and 3--butyl-2-methoxypyrazine (SBMP) in the rachis and grapes of Cabernet Sauvignon over two seasons. IBMP predominated, and its concentration in rachis and berries at harvest was significantly affected by rootstock and growing season. In the 2020 vintage, light exclusion, vine vigor, and spatial variation in vine vigor were shown to significantly affect MP concentrations in rachis.
拉姆齐砧木先前已被牵连入 8 倍左右的 3-异丁基-2-甲氧基吡嗪（IBMP）水平在穗轴（葡萄串茎）的 L. 品种设拉子接穗超过自根设拉子葡萄藤在收获。在红葡萄酒发酵过程中从穗轴中提取的 IBMP 可以产生强烈的“绿色”风味。甲氧基吡嗪（MPs）通常存在于赤霞珠葡萄、穗轴和葡萄酒中，但尚不清楚砧木是否会影响穗轴中的 MP 浓度。本研究考虑了包括拉姆齐在内的 8 种砧木对赤霞珠穗轴和葡萄中 IBMP、3-异丙基-2-甲氧基吡嗪（IPMP）和 3-丁基-2-甲氧基吡嗪（SBMP）浓度的影响在两个季节。IBMP 占主导地位，其在穗轴和浆果中的浓度在收获时受到砧木和生长季节的显著影响。在 2020 年份，光屏蔽、葡萄藤活力和葡萄藤活力的空间变化被证明显著影响了穗轴中的 MP 浓度。
