terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Application of UV-B radiation in pre- and postharvest as an innovative and sustainable cultural practice to improve grape phenolic composition

Application of UV-B radiation in pre- and postharvest as an innovative and sustainable cultural practice to improve grape phenolic composition

Abstract

Ultraviolet radiation (UVR) is a minor part of the solar spectrum, but it represents an important ecological factor that influences many biological processes related to plant growth and development. In recent years, the application of UVR in agriculture and food production is emerging as a clean and environmentally friendly technology.

In grapevine, many studies have been conducted on the effects of ambient levels of UVR, but there are few considering the effects of UV-B application on grape phenolic composition under commercial growing or postharvest conditions.

In this study, two kinds of UV-B applications were performed on Tempranillo grapes. On one hand, grape clusters at commercial maturity were supplemented with UV-B for five days before harvest, using a tractor-mounted lamp. On the other hand, postharvest bunches were irradiated with UV-B using an automated postharvest application technology.

In both cases, after UV-B application, the overall levels of phenolic compounds were analyzed, as well as the phenolic profile of the grape skins. The main response to the UV-B treatment in preharvest was an increase in flavonols, mainly quercetins. In the postharvest application, both total phenol and flavonol contents increased, while hydroxycinnamic acid derivatives showed an opposite trend, with higher concentrations in the control treatment. In neither treatment did the sugar content or acidity of the grapes change.

In conclusion, the application of UV-B, both in pre- and postharvest, improved the phenolic quality of grape skins, mainly through the increase in flavonols. Our study opens new possibilities to realistically introduce the mechanical application of supplemental UV-B radiation as an additional agricultural practice under commercial field conditions at crop scale (pre- and postharvest), in order to improve grape quality. This could be of great importance in the context of climate change in which we are immersed.

DOI:

Publication date: October 11, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Hidalgo-Sanz R., Del-Castillo-Alonso M.A., Monforte-López L., Tomás-Las-Heras R., Núñez-Olivera E and Martínez-Abaigar J.

Faculty of Science and Technology, University of La Rioja. 26006 Logroño (La Rioja), Spain

Contact the author*

Keywords

phenolic composition, grape skins, UV-B radiation, Vitis vinifera L. cv. Tempranillo

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Phenolic extraction and dissolved oxygen concentration during red wines fermentations with Airmixig M.I.™

During red wine fermentation, the extraction of phenolics compounds and sufficient oxygen provision are critical for wine quality [1,2]. In this trial, we aimed at evaluating the kinetics of phenolic extraction and dissolved oxygen during red wine fermentations using the airmixing system. Twenty lots of red grape musts were fermented in 300.000 L tanks, equipped with airmixing, using two injection regimes (i.e., high and low intensity, and high and low daily frequency). An oxygen analyzer was introduced into the tanks in order to record the concentration of dissolved oxygen over time.

Mycorrhizal symbiosis modulates flavonoid and amino acid profiles in grapes of Tempranillo and Cabernet Sauvignon 

Arbuscular mycorrhizal fungi (AMF) symbiosis is probably the most widespread beneficial interaction between plants and microorganisms. AMF has been widely reported to promote grapevine growth, water and nutrient uptake as well as both biotic and abiotic stress tolerance[1]. However, the impact of AMF on grape composition has been less studied. The aim of this work was to evaluate the effects of the association between two commercial grapevine cultivars (Tempranillo and Cabernet Sauvignon grafted onto 110 rootstock) and AMF on the anthocyanin, flavonol and amino acid concentrations and profiles of grapes.

Retrospective analysis of our knowledge regarding the genetics of relevant traits for rootstock breeding 

Rootstocks were the first sustainable and environmentally friendly strategy to cope with a major threat for Vitis vinifera cultivation. In addition to providing Phylloxera resistance, they play an important role in protecting against other soil-borne pests, such as nematodes, and in adapting V. vinifera to limiting abiotic conditions. Today viticulture has to adapt to ongoing climate change whilst simultaneously reducing its environmental impact. In this context, rootstocks are a central element in the development of agro-ecological practices that increase adaptive potential with low external inputs. Despite the apparent diversity of the Vitis genus, only few rootstock varieties are used worldwide and most of them have a very narrow genetic background. This means that there is considerable scope to breed new, improved rootstocks to adapt viticulture for the future.

High-throughput sequencing analysis based on nematode indices revealed healthier soils of organic vineyards 

Proper soil health assessments are crucial for sustainable cropland. Among the widely employed approaches, evaluating nematode community structure is particularly suitable. Traditionally, the taxonomic characterization of soil nematodes has relied on time-consuming morphology-based methods requiring experienced experts. However, molecular tools like high-throughput sequencing have emerged as efficient alternatives. In this study, we performed a metataxonomic analysis of soil samples collected from 57 vineyards in the DOCa Rioja region of Northern Spain, focusing on the impact of organic viticulture and cover cropping compared to integrated pest management (IPM) and tilling practices.

Grape pomace, an active ingredient at the intestinal level: Updated evidence

Grape pomace (GP) is a winemaking by-product particularly rich in (poly)phenols and dietary fiber, which are the main active compounds responsible for its health-promoting effects. GP-derived products have been proposed to manage cardiovascular risk factors, including endothelial dysfunction, inflammation, hypertension, hyperglycemia, and obesity. Studies on the potential impact of GP on gut health are much more recent. However, it is suggested that, to some extent, this activity of GP as a cardiometabolic health-promoting ingredient would begin in the gastrointestinal tract as GP components (i.e., (poly)phenols and fiber) undergo extensive catabolism, mainly by the action of the intestinal microbiota, that gives rise to low-molecular-weight bioactive compounds that can be absorbed and utilized by the body.