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Review
. 2021 Oct 15;11(10):1521.
doi: 10.3390/biom11101521.

Prevalence and Management of Alkyl-Methoxypyrazines in a Changing Climate: Viticultural and Oenological Considerations

Gary J Pickering  1   2   3   4   5 , Jim Willwerth  1   3 , Andreea Botezatu  6 , Margaret Thibodeau  1
Affiliations
Review

Prevalence and Management of Alkyl-Methoxypyrazines in a Changing Climate: Viticultural and Oenological Considerations

Gary J Pickering et al. Biomolecules. .

Abstract

Alkyl-methoxypyrazines are an important class of odor-active molecules that contribute green, 'unripe' characters to wine and are considered undesirable in most wine styles. They are naturally occurring grape metabolites in many cultivars, but can also be derived from some Coccinellidae species when these 'ladybugs' are inadvertently introduced into the must during harvesting operations. The projected impacts of climate change are discussed, and we conclude that these include an altered alkyl-methoxypyrazine composition in grapes and wines in many wine regions. Thus, a careful consideration of how to manage them in both the vineyard and winery is important and timely. This review brings together the relevant literatures on viticultural and oenological interventions aimed at mitigating alkyl-methoxypyrazine loads, and makes recommendations on their management with an aim to maintaining wine quality under a changing and challenging climate.

Keywords: climate adaptation; climate change; grape secondary metabolites; ladybug taint; methoxypyrazines; wine.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
The 2-isobutyl-3-(IBMP) and 2-isopropyl-3-(IPMP) methoxypyrazine are the most prevalent methoxypyrazines found in grapes and wine affected by ladybug taint, respectively.
Figure 2
Figure 2
Effective vineyard interventions for managing methoxypyrazine levels by phenological stage.
Figure 3
Figure 3
The expanding global distribution of Harmonia axyridis. Countries are shaded to indicate when H. axyridis was first identified. Readers are referred to Table S1 for primary data sources [21,88,89,90,91,92,93,94].
See this image and copyright information in PMC

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