Laimburg Research Centre, Laimburg, Italy.
Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy.
PLoS One. 2022 Aug 16;17(8):e0273166. doi: 10.1371/journal.pone.0273166. eCollection 2022.
In an era of growing international competition in modern viticulture, the study and implementation of innovative technologies to increase the production of high-quality grapes and wines are of critical importance. In this study, the non-destructive portable sensor Multiplex, based on fluorescence sensing technique, was applied to evaluate grape maturity parameters and flavonol content of the understudied Pinot blanc variety. The effects of environmental and agronomical factors on flavonol content of Pinot blanc grapes were investigated in eight vineyards characterised by different microclimatic and agronomic conditions. Furthermore, the direct impact of canopy management treatment on the flavonol dynamics of the grapes oriented in the four cardinal directions was assessed. Results highlight the positive role of moderate temperatures and direct sunlight exposure on Pinot blanc flavonol content; however, no direct vineyard-elevation effect was observed. The ability to modulate and evaluate the flavonol content in field represent crucial factors because of their potential effect on flavonoids-dependent wine characteristics, such as stability and ageing. In the present study, for the first time, two calibration curves were reported for pre- and post-veraison periods between flavonol indices and the berry skin flavonol content and a good correlation was observed between Multiplex measurement and the total polyphenolic content of grape juice. Moreover, the strong correlation between the chlorophyll index with grape juice sugar content and titratable acidity revealed the practical application of non-destructive sensors to predict the optimal harvest time for Pinot blanc grapes. In conclusion, the non-destructive fluorescence sensor Multiplex is a high-potential tool for innovative viticulture, for evaluating grape skin composition variables in white grape varieties.
在现代葡萄栽培日益国际化竞争的时代，研究和实施创新技术以提高高品质葡萄和葡萄酒的产量至关重要。在这项研究中，基于荧光传感技术的非破坏性便携式传感器 Multiplex 被应用于评估所研究的白皮诺品种的葡萄成熟度参数和类黄酮含量。研究了环境和农艺因素对白皮诺葡萄类黄酮含量的影响，在 8 个葡萄园进行了研究，这些葡萄园具有不同的微气候和农艺条件。此外，还评估了冠层管理处理对面向四个基本方向的葡萄类黄酮动态的直接影响。结果表明，适度的温度和阳光直射对白皮诺类黄酮含量有积极作用；然而，没有观察到葡萄园海拔的直接影响。在田间调节和评估类黄酮含量的能力是至关重要的，因为它们可能对类黄酮依赖的葡萄酒特性（如稳定性和陈酿）产生影响。在本研究中，首次报道了预成熟和后成熟期间两个校准曲线，用于测定类黄酮指数与浆果皮类黄酮含量之间的关系，并且在 Multiplex 测量值和葡萄汁总多酚含量之间观察到良好的相关性。此外，叶绿素指数与葡萄汁糖含量和可滴定酸度之间的强相关性表明，非破坏性传感器在预测白皮诺葡萄最佳收获时间方面具有实际应用价值。总之，非破坏性荧光传感器 Multiplex 是一种有潜力的创新葡萄栽培工具，可用于评估白葡萄品种的葡萄皮组成变量。
