Hyperspectral imaging and machine learning for monitoring grapevine physiology

Moderate wine consumption may impact several human health aspects, among others as a result of phenolic compounds present in wine and their bioactive properties. The aim of this study was to determine whether six weeks of daily, moderate Teran red wine consumption affects the levels of total cholesterol, high-density lipoprotein cholesterol – HDL, low-density lipoprotein cholesterol – LDL, and triglycerides. Sixty-eight healthy adults (46 women and 22 men) aged 25-64 years voluntarily agreed to participate in the study.

The Maillard reaction (MR) is a non-enzymatic reaction between reducing sugars and amino acids, resulting in the production of volatile and flavour-active compounds.

Each grape cultivar is composed of a population of individuals that are genetically different. Clonal selection has allowed the purification and improvement of the global quality

In 2022, wine production was estimated at around 260 million hl. This high production rate implies to generate a large amount of by-products, which include grape pomace, grape stalks and wine lees. It is estimated that processing 100 tons of grapes leads to ~ 22 tons of by-products from which ~ 6 tons are lees [1]. Wine lees are a sludge-looking material mostly made of dead and living yeast cells, yeast debris and other particles that precipitate at the bottom of wine tanks after alcoholic fermentation. Unlike grape pomace or grape stalks, few strategies have been proposed for the recovery and valorisation of wine less [2].

Valpolicella is a wine region characterized by a wide use of the technology of grape drying for the production of two red passito wines, recognized as PDOs, “Recioto della Valpolicella” and the most famous “Amarone della Valpolicella”. Geographical origin of the grapes can influence wine composition by grape chemical composition yeast behaviour during fermentation. This study investigates the impact of different commercial yeast strains on aroma profiles of wines produced with withered grapes of different origins. In addition, the influence of spontaneous fermentation is also considered. METHODS: Experimental red wines were produced with a standard winemaking protocol with withered Corvina and Corvinone grapes obtained from two different geographical areas within the Valpolicella region. Fermentations were carried out with four different commercial yeasts plus a spontaneous fermentation. Wines were analysed by means of SPE- and SPME-GC-MS techniques and sensory analysis (sorting task).