Browsing by Author "Brossard, N."

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    A Review of Tannin Determination Methods Using Spectrophotometric Detection in Red Wines and Their Ability to Predict Astringency
    (SOUTH AFRICAN SOC ENOLOGY & VITICULTURE-SASEV, 2021) Wilhelmy, C.; Pavez, C.; Bordeu, E.; Brossard, N.
    Astringency is an important sensory attribute that influences red wine quality. The astringent sensation inside the mouth is caused by a group of molecules called tannins. These molecules in wine can be determined and analysed by spectrophotometric, analytical and recently electrochemical methodologies. This article focuses on the three methods most frequently used by the wine industry: Bate Smith or acid hydrolysis method, Adams Harbertson assay or BSA tannin assay, and methylcellulose precipitation (MCP) method. These methods differ on the principle upon which they are based, as well as on the kind of tannin that they can determine. The purpose of this article is to present the main advantages and disadvantages of the three spectrophotometric methods acid hydrolysis, BSA assay and MCP methods for tannin determination in red wine, in order to review their efficacy, group of tannins each method can determine, and their suitability for astringency prediction.
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    Advances in White Wine Protein Stabilization Technologies
    (NLM (Medline), 2022) Silva-Barbieri, D.; Escalona, N.; Perez-Correa, J.R.; Salazar, F.N.; Lopez, F.; Brossard, N.
    The unstable proteins in white wine cause haze in bottles of white wine, degrading its quality. Thaumatins and chitinases are grape pathogenesis-related (PR) proteins that remain stable during vinification but can precipitate at high temperatures after bottling. The white wine protein stabilization process can prevent haze by removing these unstable proteins. Traditionally, bentonite is used to remove these proteins; however, it is labor-intensive, generates wine losses, affects wine quality, and harms the environment. More efficient protein stabilization technologies should be based on a better understanding of the main factors and mechanisms underlying protein precipitation. This review focuses on recent developments regarding the instability and removal of white wine proteins, which could be helpful to design more economical and environmentally friendly protein stabilization methods that better preserve the products´ quality.