terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Effect of ultraviolet B radiation on pathogenic molds of grapes

Effect of ultraviolet B radiation on pathogenic molds of grapes

Abstract

The fungicidal effect of UV-C radiation (100-280 nm wavelength) is well known, but its applicability for the control of pathogenic molds of grapes is conditioned by its effect on the host and by the risks inherent in its handling[1]

As an alternative, the effect in vitro of UV-B radiation (280-315 nm) on the main pathogenic molds of grapes has been studied: Botrytis cinerea, Aspergillus niger, Penicillium expansum and Rhizopus stolonifer.

The molds studied were seeded on Czapek agar plates (in triplicate) that were irradiated with UV-B radiation lamps located at a height of 25 cm, obtaining an irradiance of 16 Wm-2. Different exposure times (0, 1, 3, 6, 12 and 24 hours) were applied on two series of plates. One of the series was protected from radiation by UV radiation filters and acted as a control. After exposure, the plates were incubated at 20ºC in the darkness, assessing the degree of mold development over two weeks.

UV-B radiation caused a clear inhibitory effect on the development of the molds studied that was proportional to the irradiation dose received. The observed effect was different for each mold, being Rhizopus stolonipher and Botrytis cinerea the most sensitive to UV-B radiation. The resistance of molds to UV-B radiation has been related by different authors with mold pigmentation[2].

These results allow us to contemplate the use of UV-B radiation in the control of pathogenic molds of grapes.

References:

1)  Usall J. et al. (2016) Physical treatments to control postharvest diseases of fresh fruits and vegetables. Post. Biol. Tech., 122: 30-40, DOI 10.1016/j.postharvbio.2016.05.002

2)  García-Cela, M.E. et al. (2016) Conidia survival of Aspergillus section Nigri, Flavi and Circumdati under UV-A and UV-B radiation with cycling temperature/light regime. J. Sci. Food Agric., 96:2249-2256, DOI 10.1002/jsfa.734

DOI:

Publication date: October 6, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Hidalgo-Sanz R., Del-Castillo-Alonso M.A., Sanz S., Olarte C., Martínez-Abaigar J., Núñez-Olivera E.

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

Contact the author*

Keywords

UVR-B, pathogens molds, grapes

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

New tool to evaluate color modifications during oxygen consumption in white and red wines

Measuring the effect of oxygen consumption on the color of wines as the level of dissolved oxygen decreases over time is very useful to know how much oxygen a wine can consume without significantly altering its color. The changes produced in wine after being exposed to high oxygen concentrations have been studied by different authors, but in all cases the wine has been analyzed once the oxygen consumption process has been completed. This work presents the results obtained with the use of an equipment designed and made to measure simultaneously the level of dissolved oxygen and the spectrum of the wine, during the oxygen consumption process from saturation levels with air to very low levels, which indicate the total consumption of the dosed oxygen[1,2].

Qualitative and productive characterization of a minority variety: ‘Branco lexítimo’ in DO Ribeira Sacra (Spain)

The actual climate changes, together with the strong regulation of the European Union and Spanish government, in search of sustainable viticulture, have forced the recovery of minority varieties, expanding the range of grape varieties, as well as the possible development of wines with unique profiles. In the Ribeira Sacra DO (Spain), a comparative study of the agronomic and qualitative behavior of the ‘Branco lexítimo’ variety has been carried out, compared to the majority white variety in the DO: ‘Godello’, located in the same study plot, with identic soil and climatic conditions. The study contemplated the analysis of phenology and leaf water potential, as well as the productive results and the analysis of the must quality, during four seasons: 2018 – 2021.

Ultra-High Pressure Homogenization (UHPH): a technique that allows the reduction of SO2 in winemaking

Ultra-High Pressure Homogenization (UHPH) is an innovative, efficient and non-thermal technology that can be applied at different stages in winemaking in order to reduce or avoid the use of sulphites. During 2022 vintage, a batch of Xarel·lo must was processed by UHPH at 300 MPa with an inlet temperature (Ti) of 4 ºC. In order to verify the influence of the UHPH treatment in wine characteristics, alcoholic fermentations with this must (UHPH) were carried out and compared with a control batch (without SO2 addition (C)) and a sulphited batch, in which 60 mg/L of total SO2 (SO2) were added.

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.

The colour pattern of flower arrangements influence wine tasters’ sensory description

The arrangements of flowers and wine counterparts are inextricably linked. Whether a fundamental aspect of tablescaping or acolytes to broader entertainment rituals, they have an entangled history since ancient times. The aim of this contribution is to verify the influence of visually delicate and robust flower arrangements on individual description of wines. Changes in the sensory description of wines were investigated during subjects’ (thirty-two participants) exposure to three different conditions: the presence of delicate, robust, or totally absent flower arrangements. In each condition, the same two wines were blind tasted: a wine previously defined as delicate – a Pinot Noir from Australia, and a wine known for its robust character – a Tannat from Uruguay.