A GIS Analysis of New Zealand Terroir

In Italy, in the past two decades, the rate of temperature increases (0.0369 °C per year) was slightly higher compared to the world average (0.0313 °C per year). It has also been indicated that the number and intensity of heat waves have increased considerably in the last decades. (IEA, 2022). Viticultural zones can be classified with climatic indexes. Huglin’s index (HI) considers the temperature in a definite area and has been considered as reliable to evaluate the thermal suitability for winegrape production (Zhang et al., 2023).

The grape maturation process is being affected by the consequences of global climate change and, as a result, there is a gap at harvest time between the technological maturity of grapes (mostly the concentration of sugar and acids) and its phenolic quality. Due to this gap, the wines elaborated using those grapes show a non-adequate phenolic composition, which results in defects on its color and astringency characteristics. Astringency is mainly related to the salivary protein precipitation because of the interaction not only with wine flavanols but also with other wine phenolics, such as flavonols or different pigments.

Context and purpose of the study. Climate change accelerates grapevine’s phenology, advancing harvests by 2–3 weeks over the past 40 years negatively affecting wine style due to a lack of acidity and too much alcohol.

The region with Origin Indication Vale dos Vinhedos (IPVV) is located in the cities of Bento Gonçalves, Garibaldi and Monte Belo do Sul. It was established in November 2002, through an act of Instituto Nacional de Propriedade Industrial, according to Resolução INPI Nº. 75, of 2000, and Law Nº. 9.279 of 1996. The changes on the grape growing and wine making in the last 15 years, with the expansion of grapevines Vitis viníferas cultivation, the installation of several modern family wine companies, making wine with competitive quality, among other aspects, have enabled the implementation of concepts of Geographical Indications.

4-Ethylphenol (EP) in wine is associated with organoleptic defects such as barn and horse sweat odors. The origin of EP is the bioconversion reaction of p-coumaric acid (CA), naturally present in grapes and grape musts by contaminating yeasts of the genus Brettanomyces bruxellensis.
Yeast cell walls (YCW) have shown adsorption capacities for different compounds. They could be applied to wines in order to adsorb either CA and/or EP and thus reduce the organoleptic defects caused by the contaminating yeasts.