Grape marc is the leftover pips and skins after juice has been extracted from grapes. There is a lack of large-scale solutions to deal with increasing volumes in the wine industry.

Environmental biotechnologist Dr Shan Yi is running a two-year project with the University of Auckland funded by Bragato Research Institute looking to ‘upcycle’ marc into high-value, functional medium-chain organic acids for goods such as stock feed.

This project aims to upcycle grape marc to high-value, functional medium-chain organic acids (e.g., caproic acid) that currently rely on imported sources for goods such as stock feed. The two-year project will gain essential engineering know-how for developing a consolidated anaerobic bioprocess producing medium-chain organic acids from the organic waste feedstock. Advanced microbiological methods, such as genome sequencing will be used in conjunction with bioprocess engineering to optimize the yield and lower the running costs of the process.

Resources available from this project

Article: Turning grape marc into value with a novel engineering bioprocess

Article: Hitting the marc, Science transforming winery waste

Project summary

Researchers: Dr Shan Yi, University of Auckland

Years: 2022-2025

Funding: New Zealand Winegrowers