The week of scientific work during the 43rd OIV Congress in Mexico concluded with the adoption of 35 new resolutions
The Oenology commission passed 24 resolutions on the diverse topics such as oenological practices and substances, including use of selective plant fibres, oenological tannins, gum arabic, yeast mannoproteins among others. Moreover, three substances were classified as additives or processing aids, depending on their function. It’s important to highlight the new code of good wine-making practices intended to prevent or limit the alteration of wines by Brettanomyces bruxellensis.Finally, several resolutions concerning new methods of analysis were also approved by the Assembly.
The Health and Safety unit updated several resolutions aiming at the reduction of potentially allergenic residues. Similarly, the OIV has updated the code of good practice for the fining of wines to be applied for the use of fining agents of protein origin with allergenic potential. With regard to health, the commission has adopted recommendations for the dissemination of information on wine consumption.
The Viticulture Unit stablished the definition of functional biodiversity in the vineyard. The group of experts has been working on this resolution from 2018. Finally, the commission updated the recommendations on plant herbicides use.
Decisions concerning viticulture and the environment
In the field of viticulture, the OIV has adopted
- OIV general principles for carbon footprint reporting for companies/organisations and products in the wine sector (Resolution OIV-CST 503H-2022). The objective of this document is to provide guidance for performing, evaluating and revising the reporting of greenhouse gas calculation results under the OIV Protocol for the wine sector. A general framework addressing the requirements and options for communicating the carbon footprint of products is provided in this document. Indeed, the provision of standardised criteria for carbon footprint communication is necessary to ensure the accuracy and reliability of information provided to consumers, as well as to minimise the number of potentially confusing statements and labels.
- A definition and recommendations concerning functional biodiversity in the vineyard (Resolution OIV-VITI 677-2022). In particular, the OIV recommends supporting the development and promotion of the functional biodiversity approach and its adoption in vineyard agro-ecosystems as an important tool for sustainability in the wine sector, and encouraging the implementation of public policy measures to promote functional biodiversity in vineyard agro-ecosystems. The recommendations aim in particular to i) promote targeted actions to identify, inventory and conserve existing biodiversity in and around vineyards ii) to identify the effects of functional biodiversity on the landscape and terroir in and around vineyards, with social, environmental and economic impacts
- Guidelines for the Harmonisation of Methods and Criteria for the Exchange of Viticultural Plant Material - Phytosanitary and Genetic Aspects (Resolution OIV-VITI 565-2022). The main objective of these guidelines is to define principles and practices to guarantee and preserve the genetic quality and the initial phytosanitary level of the plants in all stages of vegetative propagation. In addition, these guidelines consider and recommend minimum requirements for the exchange of plant material for each type of vine variety and may also facilitate international agreements between producers and importers of vine plant material.
- OIV recommendations on alternatives to the use of herbicides in vineyards (Resolution OIV-VITI 705-2022). For the OIV, it is important to launch or develop actions to study the feasibility of the transition to alternative practices to weed control in the vineyard. Furthermore, these recommendations mention different actions to be undertaken to encourage alternative products and/or viticultural practices in order to promote the sector's sustainability objectives, in particular those directly related to sustainable soil management
- The definitions of grape nectar and carbonated grape nectar (Resolution OIV-VITI 678A-2022). Grape nectar is defined as a non-fermented beverage for direct consumption for which certain specifications are given and which must contain a minimum quantity of 50% grape juice and/or grape purée.In the case of carbonated grape nectar, this drink has had carbon dioxide added.
Decisions concerning oenological practices
Several resolutions concerning new oenological practices will complete the OIV's International Code of Oenological Practices, in particular:
The classification as additives or processing aids of various compounds already accepted by the OIV, in particular:
-The classification of carbon dioxide as an additive or processing aid according to the oenological objective considered (Resolution OIV-OENO 567B2-2022).
-The classification of skimmed milk as a processing aid, given that skimmed milk is a foodstuff used in oenology as a processing aid (Resolution OIV-OENO 567C1-2022).
-Furthermore, the OIV considered that according to the legislation, DMDC is considered as an additive in certain countries whereas in others it is considered as a processing aid (Resolution OIV-OENO 567B4-2022).
- Updating the use of selective plant fibres in musts (Resolution OIV-OENO 684B-2022) and wines (Resolution OIV-OENO 684A-2022) in order to i) reduce the content of ochratoxin A in wines; ii) reduce the number and content of residues of phytosanitary products in wines. For wines, the recommended dose is to be determined according to the filtration technique used, and does not exceed the dose of 1.5 kg/m² of filtering surface and 200 g/hL. For musts, the dose to be used is determined according to the must and the content of molecules to be adsorbed and does not exceed 200 g/hL.
- The relative modification of the current limit for the treatment of wines with gum arabic by stipulating that the dose to be used may not exceed 0.8 g/L for red liqueur wines and 0.3 g/L for other wines (Resolution OIV-OENO 689-2022).
- The deletion from the International Code of Oenological Practices of the oenological treatment with silver chloride and also the deletion from the International Oenological Codex of the monograph COEI-1-CHLARG, concerning silver chloride (Resolution OIV-OENO 707-2022)
- The modification of the oenological practice relating to flotation by specifying that clarification may be carried out either in the absence of air using nitrogen or argon, or with compressed air to favour the oxidation of oxidisable compounds and make the colour of the wine more stable (Resolution OIV-OENO 708-2022).
- The adoption of a new code of good wine-making practices intended to prevent or limit the alteration of wines by brettanomyces bruxellensis (Resolution OIV-OENO 686-2022). This code sets out all possible interventions in the vineyard, during the harvest and in the cellar to limit the development of brettanomyces bruxellensis.
Decisions on specifications for oenological products
The following monographs complement the International Oenological Codex, in particular:
The general principles to be taken into account in the evaluation of oenological practices and substances in oenological products (Resolution OIV-OENO 602-2022). According to these principles, the oenological practices and substances recommended and published by the OIV should only be used for the purposes described and in the manner described to serve as a reference for good manufacturing practices.
Furthermore, the OIV recommends maximum numerical doses for the use of oenological substances, with an acceptable daily intake (ADI). The OIV also recommends numerical limits for the best use of the technological function and/or for quality purposes, based on experimental data analysed by its own experts. In the absence of a numerical limit set by the OIV, it then recommends that oenological substances be used at levels established for good manufacturing practice (GMP), corresponding to the lowest possible level required to perform the required technological function.
The update of the general monograph on tannins (Resolution OIV-OENO 624-2022). Tannins are divided into two classes according to the nature of the monomeric units that characterise them: hydrolysable tannins and condensed tannins or proanthocyanidic tannins. In addition, detailed specifications accompany this monograph
The specific monograph on oenological tannins containing procyanidins / prodelphinidins (Resolution OIV-OENO 675A-2022). Procyanidins / prodelphinidins are a subclass of condensed tannins (or proanthocyanidins). This subclass includes tannins from grapes, skins and seeds of Vitis vinifera.
The specific monograph on oenological tannins containing ellagitannins (Resolution OIV-OENO 675B-2022). Ellagitanins are a subclass of hydrolysable tannins. Included in this subclass are tannins from chestnut and oak wood.
The specific monograph on preparations containing gall tannins (Resolution OIV-OENO 675C-2022). Gallic tannins or gallotannins are a subclass of hydrolysable tannins. Included in this subclass are tannins from oak (and chestnut) galls and from the pods of Tara (Caesalpinia spinosa)
The specific monograph on oenological tannins containing profisetinidins / prorobitinidins (Resolution IVD-OENO 675D-2022). Profisetinidins / prorobitenidins are a subclass of condensed tannins (or proanthocyanidins). Included in this subclass are tannins from quebracho and acacia spp.
The update of the monograph on yeast extracts containing mannoproteins (Resolution OIV-OENO 674-2022). This amendment concerns the addition of a specification on the insoluble dry matter content. A method for determining the percentage of insoluble dry matter is included in this monograph.
Powdered cellulose is a food grade cellulose (Resolution OIV-OENO 681-2022). It plays a role of "support" in clarified fermentation media, it allows a better "degassing" of carbon dioxide at the beginning of alcoholic fermentation and thus shortens the lag phase. It increases the fermentability of the juice.
Decisions concerning methods of analysis
At this same session, new methods of analysis will be added to the OIV's analytical corpus. These are in particular:
The OIV opinion on dry extract, which stipulates that the sole measurement of total dry extract, total dry matter, dry extract without sugar or residual extract is not sufficient for the detection of possible fraud (Resolution OIV-OENO 668-2022).
The method for the determination of ochratoxin A in grape juice, reconstituted grape juice, concentrated grape juice and grape nectar after passage through an immunoaffinity column and high performance liquid chromatography with fluorimetric detection (Resolution OIV-OENO 662A-2022). This method uses an immunoaffinity column and high performance liquid chromatography (HPLC). OTA is eluted with methanol and quantified by reverse phase HPLC with fluorometric detection.
The method for the determination of volatile acidity in grape juice, reconstituted grape juice, concentrated grape juice and grape nectar (Resolution OIV-OENO 662C-2022). The principle of this method is that the volatile acids are separated from the grape juice, reconstituted grape juice, concentrated grape juice and grape nectar by steam distillation and then titrated with the sodium hydroxide solution of known concentration
The method for determining the 18O/16O isotopic ratio of water in grape juice (Resolution OIV-OENO 662H-2022). This method is based on equilibration between CO2 and water in grape juice. After equilibration, the carbon dioxide in the gaseous state is used for analysis by isotope ratio mass spectrometry (IRMS), where the 18O/16O isotope ratio is determined in the equilibrated CO2.
The method for the determination of sweeteners in white wine and white wine-based beverages (OIV-OENO Resolution 665-2022). This method allows the determination of five artificial sweeteners (Acesulfame-K, Aspartame, Saccharin, Sodium Cyclamate, Sucralose) in white wine (and white wine-based beverages). The five sweeteners are analysed by high performance liquid chromatography coupled to a diode array detector and a charged aerosol detector arranged in series (HPLC/UV-CAD).
The modification of the OIV method on chromatic characteristics by introducing an annex relating to the operating instructions for the determination of chromatic characteristics applicable to red wine with a high concentration of colouring pigments, to must and to must containing a high level of sulphur dioxide (Resolution OIV-OENO 667-2022). The principle is based on a spectrophotometric method by which the chromatic characteristics are, by convention, the intensity of the colour, given by the sum of the absorbances, and the hue, expressed as the ratio between the absorbance at 420 nm and the absorbance at 520 nm.
The update of the OIV method on the quantification of total nitrogen according to the Dumas method (OIV-OENO Resolution 683-2022). This method applies to the analysis of total nitrogen in musts and wines up to 1000 mg/L. The analysis of total nitrogen consists of a total combustion of the matrix under oxygen at a temperature higher than 900°C, followed by a complementary oxidation. The nitrogen oxides are then reduced to nitrogen, which is quantified using a thermo-conductive detector.
Decision on Economy and Law
The OIV has adopted the update of article 3.1.9 "Medals and distinctions" of the OIV International Standard for the labelling of wines (Resolution OIV-ECO 685-2022). The main modifications are intended to allow wines without a geographical indication or appellation of origin to take part in competitions, and that medals and awards received by an individual wine bear the name of the competition and the year of award. The main changes aim to allow wines without a geographical indication or designation of origin to take part in competitions, and for medals and awards received by an individual wine to bear the name of the competition and the year of award.
Decisions on Safety and Health
- The OIV has updated the resolution on "Criteria for methods of quantification of potentially allergenic fining protein residues in wine" by keeping a detection limit of 0.25 mg/L and a quantification limit of 0.5mg/L for caseinates, ovalbumin, isinglass and lysozyme (Resolution OIV-SECSAN 709-2022). It is also recognised that no specific method has been defined for the determination of fining proteins in wine and that several ELISA methods are already available and applicable.
- Similarly, the OIV has updated the code of good practice for the fining of wines to be applied for the use of fining agents of protein origin with allergenic potential by specifying that if the usual analytical methods for food allergens do not detect any allergenic protein in the wine, then it can be considered that no residue above the detection limit is present (Resolution OIV-SECSAN 710-2022). However, the choice of the analytical method to be applied and the relative limits of detection and quantification is the responsibility of the producer. If a national/supranational limit exists, it is recommended that Member States and producers use the criteria suggested by the OIV.
- The OIV has, on the basis of the new toxicological evaluation of arsenic in foodstuffs, reduced the arsenic limit in wine from 0.2 mg/L to 0.1 mg/L for wine produced from the 2023 harvest onwards (Resolution OIV-SECSAN 701-2022).
- With regard to health, the OIV has adopted recommendations for the dissemination of information on wine consumption (Resolution OIV-SECSAN 679-2022). Thus, the OIV, on the basis of work at international level, recommends that communication directed at wine consumers should contain certain information adapted to the occasions of consumption and to certain target populations, and also recognises that further research is necessary, particularly on certain subjects.
- Finally, the OIV has adopted recommendations on the evaluation/appraisal and communication of epidemiological studies on the consumption of grapes, wine and other wine products (Resolution OIV-SECSAN 711-2022). The OIV recommends that certain criteria be taken into consideration in the evaluation/assessment and communication of epidemiological studies on the consumption of grapes, wine and other wine products. Similarly, an assessment of the risk of bias should be carried out in accordance with the well-known guidelines for conducting studies. Finally, the OIV recommends that certain criteria be taken into account for any communication relating to epidemiological studies on the consumption of grapes, wine and other wine products.