Publicação

Effects of time variable water deficit, defoliation and crop load reduction on the juice and wine composition of Vitis vinifera L. cv. Solaris, analysed by FT IR Spectroscopy and 1 H NMR Spectroscopy

Detalhes bibliográficos
Resumo:	Water deficit at different tim es during the phenological cycle was induced in pot grown Vitis vinifera L. cv. Solaris while severe de fo liation and severe crop load reduction was carried out in field grown Solaris plants. Juice and wine samples were obtained by all treatment groups and me asured by Fourier Transform Infrared (FT IR) Spectroscopy and Proton Nuclear Magnetic Resonance 1 H N MR Spectroscopy. Chemometric data analysis was performed by PCA on a variety of different data sets. Water stress timing did not alter the composition of juice and wine in Solaris compared to an irrigated control group, but pruning type showed an influenc e on composition S ingle cane pruned vines show ed a tendency to higher values in most examined parameters when compared to double cane vines. A clear sampl e distribution was visible among the field groups. Crop thinning proved to be a reliable practice to in crease sugar content and ripeness parameters while defoliation showed a decreasing effect on sugar accumulation and ripeness and an increasing effect on tartaric acid. 1 H NMR was found to be a useful tool to differentiate between the samples of the two e xp eriments in both juice and wine and metabolites responsible for this sample distribution could clearly be identified by PCA. NMR based metabolomics are c oncluded to be a promising technique for future wine research.
Autores principais:	Nittnaus, Andreas Paul
Assunto:	grapevine water stress defoliation crop thinning 1H-NMR
Ano:	2019
País:	Portugal
Tipo de documento:	dissertação de mestrado
Tipo de acesso:	acesso aberto
Instituição associada:	Universidade de Lisboa
Idioma:	inglês
Origem:	Repositório da Universidade de Lisboa

Descrição
Resumo:	Water deficit at different tim es during the phenological cycle was induced in pot grown Vitis vinifera L. cv. Solaris while severe de fo liation and severe crop load reduction was carried out in field grown Solaris plants. Juice and wine samples were obtained by all treatment groups and me asured by Fourier Transform Infrared (FT IR) Spectroscopy and Proton Nuclear Magnetic Resonance 1 H N MR Spectroscopy. Chemometric data analysis was performed by PCA on a variety of different data sets. Water stress timing did not alter the composition of juice and wine in Solaris compared to an irrigated control group, but pruning type showed an influenc e on composition S ingle cane pruned vines show ed a tendency to higher values in most examined parameters when compared to double cane vines. A clear sampl e distribution was visible among the field groups. Crop thinning proved to be a reliable practice to in crease sugar content and ripeness parameters while defoliation showed a decreasing effect on sugar accumulation and ripeness and an increasing effect on tartaric acid. 1 H NMR was found to be a useful tool to differentiate between the samples of the two e xp eriments in both juice and wine and metabolites responsible for this sample distribution could clearly be identified by PCA. NMR based metabolomics are c oncluded to be a promising technique for future wine research.