自轉色期（véraison）初始Grenache 單一果串（2022/07/19的樣本）果實中，附圖顯示出果實新鮮總量與°Brix（糖分濃度）的變異性。
綠色莓果質地柔軟，並開始累積糖分。在果實糖分累積逐漸衰退，並結束於18-20 °Brix的果實糖分承載平線期（plateau of berry sugar accumulation）後，果皮中花青素（anthocyanin）開始進行生物合成（biosynthesis）。(Fournand et al., 2006)
這種變異性與源於花期至受粉、果串中的葡萄非同步發展有關。每顆果實的種籽數量，也會有所影響。
果實非同步發展的問題，很難在葡萄園中管理。
關鍵訊息
- 一串葡萄中，每顆果實有自己發展與成熟的狀態（Shahood et al., 2020）
- 無關採收日期，果實在採收時並未處在相同的成熟狀態
- 葡萄園、葡萄藤、果串與果粒的異質性是葡萄園的現實情況，這會影響到葡萄酒的香氣輪廓（Bramley et al., 2019）
- 就葡萄酒的香氣輪廓，採收日期是關鍵的（具新鮮與成熟水果的葡萄酒類型），不考慮品種 x 環境條件（Antalick et al., 2021；Schmidtke et al., 2020）
進一步資訊
- Guillaume Antalick et al., “Performing Sequential Harvests Based on Berry Sugar Accumulation (mg/berry) to Obtain Specific Wine Sensory Profiles,” OENO One 55:2 (2021), pp. 131-146.
- R. G. V. Bramley et al., “Spatio-Temporal Variability in Vine Vigour and Yield in a Marlborough Sauvignon Blanc Vineyard,” Australian Journal of Grape and Wine Research 25:4 (2019), pp. 430-438.
- Alain Carbonneau et al., Traité de la Vigne – Physiologie, Terroir, Culture (Paris: Dunod Editeur, 2020).
- David Fournand et al., “Accumulation and Extractability of Grape Skin Tannins and Anthocyanins at Different Advanced Physiological Stages,” Journal of Agriculture and Food Chemistry 54:19 (2006), pp. 7331-7338.
- Michael G. Mccarthy and B. G. Coombe ,”Is Weight Loss in Ripening Grape Berries cv. Shiraz Caused by Impeded Phloem Transport?” Australian Journal of Grape and Wine Research 5:1 (1999), pp. 17–21.
- Rezk Shahood et al., “First Quantitative Assessment of Growth, Sugar Accumulation and Malate Breakdown in A Single Ripening Berry,” OENO One 54:4 (2020), pp. 1077-1092.
- Leigh M. Schmidtke et al., “Cultivar, Site or Harvest Date: The Gordian Knot of Wine Terroir,” Metabolomics 16:5 (2020), pp. 1-17.
Professor Alain Deloire
