Application of satellite-derived vegetation indices for frost damage detection in grapevines

AIM AND METHODS: Corvina and Corvinone are the two main grape varieties used in the production of Valpolicella, Recioto and Amarone, top-quality red wines in north-eastern Italy. This work aimed at determining the aroma composition of Corvina and Corvinone experimental wines and identify the main aroma compounds contributing to the aroma characteristics of Corvina and Corvinone monovarietal wines. Five Corvina and five Corvinone wines were studied, the grapes coming from five different vineyards in Valpolicella. Volatile compounds were extracted by SPE and identified and quantified by gas chromatography-mass spectrometry (GC-MS), whereas their aroma impact was determined by gas chromatography- olfactometry (GC-O).RESULTS: Based on the GC-MS-O analysis, 95 odor zones were detected, from which 68 compounds were successfully identified. Using the criterion of a value higher than 30% in modified frequency (MF %), 51 compounds were selected and grouped according to odor similarity. Compounds with values below 30% were discarded.

More recently, studies have shown that polyphenols could also prevent or improve vision in patients with ocular diseases and especially age-related macular degeneration (AMD) which is an eye disease characterized by damage to the central part of the retina, the macula, and that affects millions of people worldwide. Despite therapeutic advances thanks to the use of anti-vascular endothelial growth factor (VEGF), many resistance mechanisms have been found to accentuate the visual deficit.

Mannoproteins (MPs) are proteoglycans from the outmost layer of yeast cell walls released into wine during alcoholic fermentation and ageing on lees processes. The use of commercial preparations of mannoproteins as additives to improve wine stability with regards to the crystallization of tartaric salts and to prevent protein haze in the case of white and rosé wines is authorized by the OIV.
Regarding red wines and polyphenols, mannoproteins are described as able to improve their colloidal stability and modulate the astringent effect of condensed tannins. The latter interact with salivary proteins forming insoluble aggregates that cause a loss of lubrication in the mouth and promote a drying and puckering sensation. However, neither the interaction mechanisms involved in mannoproteins capacity to impact astringency nor the structure-function relationships related to this property are fully understood.

This project aims on monitoring the plant development and comparison of the effects of various training systems on vine fertility and physiological processes.

The Tokaj Kereskedőház Ltd. is the only state owned winery in Hungary. The company is integrating grapes for wine production from 1100 hectares of vineyard, which consist of 3500 parcels with average size of 0,3 hectares, owned by about 500 families of the region. The vineyards are unevenly spread in total 27 village of Tokaj region.