Project Number
SU ProE 17-01
Project title
Pilot study on the separation and purification of resveratrol from wine waste using aqueous two-phase separation
Project leader
Pott, R
Institution
Stellenbosch University. Department of Process Engineering
Objectives and Rationale
Grapes contain the valuable antioxidant resveratrol. This project aimed to develop a process for the recovery of resveratrol from waste-biomass. We first explored which biomass contained the most resveratrol: highly variable, but stems and canes showed the highest, followed by skins. We then demonstrated the use of ATPS for the purification of resveratrol, and methods for precipitating the product.
Methods
Waste biomass (stems, canes, leaves, pressed grapes, pomace and liquid effluent) was collected from a number of vineyards around Stellenbosch and Brenn-o-kem. These were stored at -20°C until needed.
Aqueous two phase separation was developed to extract, purify and recover the resveratrol – based on salt and polymer addition. Resveratrol precipitation was initiated with protein addition, or a second maltodextrin-based ATPS.
Resveratrol was quantified using HPLC, while total phenolics were determined using the standard FC assay.
Key Results
Several waste biomass streams from viticulture have significant resveratrol (and phenolic) amounts – particularly stems containing high concentrations.
ATPS can be used to effectively extract, and concentrate resveratrol, and precipitation can recover this into a solid product.
Preliminary economic analysis suggests there may be value in developing a process to produce resveratrol products from waste biomass.
Key Conclusion of Discussion
New understanding has been developed for:
- which portions of viticulture biomass have significant resveratrol concentrations
- novel ATPS formulations for extracting, purifying and recovering a resveratrol product
This has resulted in one accepted paper thus far, and a patent on the process.
The work may prove to have application in generating an additional value stream from underutilized viticulture biomass.
Take Home message for Industry
Waste sometimes has components of significant value – in this case, resveratrol.
We have developed a process for extracting and recovering the resveratrol out of this biomass.
Final report
The final report contains intellectual property related to a patent application and can therefore not be published.