Air speed and plastic crate vent‐holes for wine grape quality during postharvest dehydration: commercial and laboratory studies

Abstract

BACKGROUNDAirflow is an important issue to favor postharvest dehydration keeping wine grape quality. The aim of this experimental work was to analyze the grape quality during postharvest dehydration: (i) in a commercial facility (‘fruttaia’) by monitoring the efficiency of the ventilation system and (ii) at laboratory level, studying the influence of crate type and airflow direction.RESULTSIn the fruttaia, the airflow was provided by an air duct hanging from the ceiling, and by floor fans. A great gap in air speed from 0 up to 3.7 m s−1 was measured in different sectors of the fruttaia, leading to a different weight loss and grape quality in crates, depending on crate stack height and sector. At the laboratory level, two tunnels, with exhaust or supply fans, were used and four crate types with different percentages of vent‐holes were adopted. A decrease of about 5% delayed the weight loss rate depending on the type of crate, and the exhaust fan guaranteed a faster dehydration.CONCLUSIONThe results clarified the inefficiency of the commercial ventilation system in ensuring homogeneous grape weight loss in all crates. In addition, the exhaust fan guaranteed a more uniform air distribution around crates, and a slightly higher air speed. © 2023 Society of Chemical Industry.

Novelty of Italian Grape Ale (IGA) beer: Influence of the addition of Gamay macerated grape must or dehydrated Aleatico grape pomace on the aromatic profile

“…The pomace used, on the other hand, was grapes cv Aleatico ( Vitis Vinifera L.) manually harvested in September 2021, at the Fattoria di Calappiano (Sensi Vigne & Vini, Lamporecchio, Italy). The bunches were placed in perforated plastic crates for the dehydration process in a ventilated tunnel (temperature = 20 ± 2 °C; humidity = 65 ± 3 °C; airflow = 1 m/s; time = 20 days), up to 40% of weight loss [ 17 ]. At the end, the bunches were pressed with a pneumatic press 40 L (Polsinelli Enologia Srl, Isola del Liri, Italy), and the pomace, left over from the juice extraction, was used in the production of IGA-P beer.…”

Is there any influence of biodynamic preparation 501 on the physiological activity of grape leaves cv. Cesanese d’Affile?

“…Consequently, several studies have linked Si with elevated shoot and root activities of antioxidants, both enzymatic (e.g., superoxide dismutase, peroxidase, catalase, ascorbate peroxidase and glutathione reductase) and non-enzymatic (e.g., ascorbate, glutathione, phenolic compounds, etc. ), as well as changes in the concentrations of common markers of oxidative stress, including malondialdehyde, hydrogen peroxide (H 2 O 2 ) and proline, under various abiotic stresses [68,69].…”

Postharvest wine grape dehydration: ethanol dissipation from grape and biochemical changes

“…1 O 2 increases towards the central axis corresponding to the presence of air spaces that are connected to the pedicel where lenticels are located, which are important for berry O 2 uptake as a function of temperature; when lenticels are blocked, a hypoxia condition starts in grape berries, as well as ethanol accumulation and CD. [2][3][4] Xiao et al 5 demonstrated that, in non-irrigated vines, berry O 2 decreased, whereas both CD and ethanol concentration increased. Water stress is the typical stress occurring during postharvest wine grape dehydration, which induced great changes in terms of metabolism.…”