OIV Approves New Global Standard for Measuring Acidity in Grape Juice Products

Global exports of grape juice have increased by more than 80% over the past two decades, according to recent data from the International Organisation of Vine and Wine (OIV). In 2024, the value of these exports reached EUR 866 million, reflecting a significant expansion in the sector. This growth has prompted renewed attention to scientific standards and international cooperation.

Last week, representatives from the OIV and the International Fruit and Vegetable Juice Association (IFU) met at the OIV headquarters in Dijon, France. The meeting focused on technical cooperation related to grape juice, with particular emphasis on laboratory methods for analysis and improved data sharing. Both organizations discussed current analytical protocols used to ensure reliability and authenticity in grape juice testing. They also explored ways to harmonize statistical collection and monitoring practices to better understand trends in the global market.

One of the main topics was the adoption of new standards for determining total acidity in grape juice and related products. The OIV General Assembly recently approved a resolution outlining a standardized method for measuring total acidity by titration. This method applies to grape juice, reconstituted grape juice, concentrated grape juice, and grape nectar. The procedure uses potentiometric titration or titration with bromothymol blue as an indicator, with a preference for potentiometric titration due to its sustainability.

The method specifies detailed steps for sample preparation, reagent use, calibration, and calculation of results. For concentrated grape juice, samples are diluted before analysis. For other products, carbon dioxide is removed prior to testing. The titration is performed until a pH of 7.0 is reached at 20°C. The results are expressed in milliequivalents per liter or kilogram, as well as in grams of tartaric or sulfuric acid per liter.

Validation studies have shown that the method offers high precision and repeatability across a wide range of acidity levels. The standardization aims to ensure that laboratories worldwide can produce comparable results, supporting transparency and trust in international trade.

The rapid growth in global grape juice exports has increased the need for robust scientific standards and reliable data. By strengthening cooperation between organizations like OIV and IFU, industry stakeholders hope to support the entire grape value chain—from growers to exporters—through improved information sharing and harmonized analytical methods.

The meeting in Dijon highlighted the importance of ongoing dialogue between scientific bodies and industry groups as the sector continues to expand. With exports rising sharply and markets becoming more interconnected, clear standards and effective monitoring are seen as essential tools for maintaining product quality and consumer confidence worldwide.