Many NMR-based metabolomics studies on grapevine have been reported; however, they have mainly been used for the classification of wine products based on their polyphenolic composition. For example, NMR coupled with multivariate statistics has proved to be a suitable method for studying the effect of environmental vineyard conditions on the chemical composition of grapes and their wines  or for the differentiation of wines based on grape varieties . A similar approach was used recently for studying the in vitro bioconversion of polyphenols from red wine and grape juice by human intestinal microbiota .
Recently, a NMR-based metabolomic studies related to stress responses in grapevines affected by the esca wood disease (a fungal community infection that leads to grapevine apoplexy) was published. In this work the metabolic changes in control versus diseased leaves were fingerprinted using 1D and 2D NMR. Principal component analysis (PCA) of the NMR spectra showed a clear separation between the groups, indicating a difference in compound production due to the esca disease. The study revealed a significant increase in phenolic compounds accompanied by a decrease in carbohydrates, suggesting that carbon and energy were rerouted from primary to secondary metabolism in the diseased leaves .
NMR is also an invaluable tool for the de novo structure determination of stilbenes, and numerous papers have dealt with issues related to stilbene identification . Recently, for example, it has been shown that the establishment of stilbene configuration, a challenging task, can be elegantly established based on 1H-NMR and the theoretical calculation of chemical shifts .
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WHAT IT IS A three-phase plan that has been likened to the low-carbohydrate Atkins program because during the first two weeks, South Beach eliminates most carbs, including bread, pasta, potatoes, fruit and most dairy products. In PHASE 2, healthy carbs, including most fruits, whole grains and dairy products are gradually reintroduced, but processed carbs such as bagels, cookies, cornflakes, regular pasta and rice cakes remain on the list of foods to avoid or eat rarely.