A low-cost optical system for in-line automated fermentation control

Batch fermentations are traditionally used in the production of wine and other fermentations and suffer from large concentration gradients that may cause stress to production organisms and affect fermentation success. Fed-batch fermentations address these issues. We demonstrated recently that a certain kind of innovative fed-batch fermentation dramatically reduces yeast stress and acetic acid formation in wine fermentations. This type of vinification is highly innovative and opens significant opportunities for improving fermentations and product quality. However, it requires automatic analysis of sugar concentrations in order to regulate the feeding rate. Lately, the applicant demonstrated that FTNIR is capable of providing continuous in-line analysis of sugar concentrations during fermentations. This method provides the required proof-of-concept, but an alternative technology to a research grade FTNIR has to be found, since the current cost of ~50-70k for the equipment constitutes a barrier for commercial success.

For this project, we have formed an interdisciplinary research partnership composed of personnel from HES- CHANGINS and HE-ARC with expertise in industrial microbiology, automation, optical engineering and electronic processing.

The partners have identified several synergistic approaches to reduce overall system cost. These comprise multiplexing the liquid handling of the measurement system as well as low-cost analytical alternatives including spectrophotometic methods.

Accordingly, we propose developing and implementing a multiplexed low-cost optical system for the quantification of key parameters that allows for in-line control of grape wine fermentations under practical conditions. The project will be driven by the expertise of HES-ARC with optical hardware and the establishment of calibration models, and the know-how of HES-CHANGINS with regards to fermentations and automation technology. Given the opportunities for both optical equipment and process automation manufacturers in Switzerland, as well as for the improvement of wine quality from application of modern vinification methods, we are convinced that the current project has a high potential for success, and partnerships.

Project manager in Changins Dr Ramón Mira de Orduña Heidinger Professor of Wine Chemistry T +41 22 363 40 27

2015 – 2018

Partners: HE-ARC

Funding: HES-SO