Resumen de Winery On-site Assessment of Grapevine Bunch Rot: In Pursuit of Sustainable Practices
R.J. Cornelissen, José Luis Aleixandre Tudó, H. Nieuwoudt
Producer wineries are responsible for processing 75 % of South Africa's annual wine grape production. A characteristic of producer wineries is the processing of large volumes of wine grapes, thus incorporating enormous variability in grape quality, which includes the presence of grapevine bunch rots. Grapevine bunch rots are detrimental to grape and wine quality. The "Introduction" provides background information on the industrial working conditions at producer wineries and the economic effect of rot on wine production. The next two sections discuss the principal reasons for bunch rot being an inevitable part of grape production, namely cultivar susceptibility and climatic conditions. The challenges regarding grapevine bunch rot assessment, specifically concerning producer wineries or wineries processing large amounts of grapes, are set out in "Assessing rot intensity". Representative sampling, mechanical harvesting of grapes and visual evaluation are discussed from an industrial perspective. The last section of this review focuses on the quest for sustainable appraisal of grapevine bunch rot. Infrared spectroscopy (IR) could provide a sustainable option for objectively assessing rot on-site at producer wineries. However, even with the availability of plenty of spectroscopic methods and the demonstrated potential of IR spectroscopy for rapid assessment of grapevine bunch rot, these methods are yet to be applied routinely under industrial working conditions.
