Integrated Human Practice
Following our human practice investigation, we challenged ourselves to tackle the specific requirements, of both the consumers and the industry. We designed our research around the three prominent issues we learned and thought about for the creation of a new approach in the wine industry.
The wine industry was mainly concerned about recurring infections that cause financial losses and the destruction of whole wine barrels. So, our first mission was - “Fighting the bad yeast”. We scoured professional literature regarding Brettanomyces bruxellensis a common contaminant of red wine, that thrives during the aging stage. Red wine contaminated with Brett is characterized by taints described as ‘phenolic’, ‘horsy’ and ‘leather’. These are a result of Brett’s metabolic products which are mainly volatile phenols, tetrahydropyridines and acetic acid. Brett causes a great deal of losses to wineries each year and is traditionally controlled by the use of sulphur dioxide (SO2). (1)
After we explored about Brett and search the literature - we encountered a protein called KP6. Mixed cultures in winemaking conditions show that KP6 protein has the ability to inhibit B. bruxellensis, while S. cerevisiae is fully resistant to its killer activity, indicating that it could have been used in wine fermentation to avoid the development of B. bruxellensis without undesirable effects on the fermentative yeast. because of contamination or to the survival of some strains, spoilage sometimes occurs during ageing or even after bottling and some wines cannot be sold because of their abnormal viscosity, resulting in considerable financial loss.
All this can be explained by the fact that identification of Brettanomyces bruxellensis is particularly difficult in the early stages of wine production, and as a result, treatment is now performed after identification, when its effect is already felt, albeit at a minimal level of feeling. We offer a 'preventative treatment' that will allow the winemakers to keep wine clean from Brettanomyces bruxellensis from the stage of alcoholic fermentation, so the winemaker can avoid wine throwing or unnecessary addition of sulphur dioxide (SO2).
Our second mission was to lower the sugar content of the wine, without sacrificing its quality.
The target market for this endeavor consists of diabetic individuals and people suffering from other metabolic irregularities. We wanted to create a wine with all its classic aromas and flavors but with zero glycemic index. That’s when we realized that the answer lies with the “Miracle Fruit” (Synsepalum dulcificum) , a fruit that alters the perception of taste in such a way that sour foods are perceived as sweet.
Due to this unique attribute, Miraculin is potentially perfect as an artificial sweetener that does not raise blood sugar levels.
Miraculin consists of four subunits and he’s molecular weight is 24.6 KDa. The molecule itself is not sweet, however, after the taste buds are exposed to miraculin (which binds to sweet receptors on the tongue), acidic foods which are ordinarily sour (in the pH range of 3-6 pH) are perceived as sweet. The action mechanism is unclear yet, but we believe the benefit of Miraculin can implemented in the wine industry, in order to design a wine product dedicated to diabetes and overweight consumers.
Third, Resveratrol. We learned from the people we interviewed, wine consumers and health conscious to boot, that a healthier wine is a much desired product. Resveratrol has been the focus of much research over the last 20 years (graph 1), because of its promise as an elixir of youth and health (graph 2). Research proves that it does have anti-aging, anti-inflammatory, antioxidant, antiplatelet and anti-cancer effects as:
inhibiting the cytochrome P450 enzymes required for the activation for transformation of some cancer-producing chemicals to their active forms.
restores the ability of cancer cells to enter into the programmed cell death response, or apoptosis, which is a normal cellular response to irreparable DNA damage.
Regarding lowering ethanol levels in wine, it became clear almost immediately that the glycerol pathway holds the key.Rational engineering strategies to redirect carbon flux from ethanol towards glycerol have provided great insight into potential biological mechanisms to lower alcohol content in wine. Numerous studies showed that by converting the metabolic pathway away from ethanol production and towards glycerol, you have wine that’s less alcoholic, but is unmarred by unwanted characteristics, that occur in alternative pathways. Sugar fermentation in S. cerevisiae is a redox neutral process influenced by the NAD+/NADH balance. Most of NAD+ is reduced during glycolysis in the reaction catalysed by the enzyme glyceraldehyde‐3‐phosphate dehydrogenase. For glycolysis to proceed, it is essential to recycle NAD+ and oxidize NADH, otherwise glycolytic flux decreases, potentially leading to the depletion of ATP energy charge which could be lethal for the cell. Most of the NADH produced during glycolysis is subsequently oxidized during ethanol formation, although NAD+ regeneration can also occur via the cytosolic production of glycerol which is catalysed by the enzyme glycerol‐3‐phosphate dehydrogenase. In addition to ethanol, the production of several metabolites that can influence wine flavour and aroma, such as glycerol and acetic acid, is linked to redox balance. Thus, altering NAD+/NADH balance has been used to redirect carbon flux towards desired end‐points, for example glycerol. (4)
Please read more about our project design here
Delaherche, A., Claisse, O. and Lonvaud-Funel, A. (2004), Detection and quantification of Brettanomyces bruxellensis and ‘ropy Pediococcus damnosus strains in wine by real-time polymerase chain reaction. Journal of Applied Microbiology, 97: 910–915. doi:10.1111/j.1365-2672.2004.02334.x.
Tomé-Carneiro, J., Larrosa, M., González-Sarrías, A., A Tomas-Barberan, F., Teresa Garcia-Conesa, M., & Carlos Espin, J. (2013). Resveratrol and clinical trials: the crossroad from in vitro studies to human evidence. Current pharmaceutical design, 19(34), 6064-6093.
Wein,H. (2013) how resveratrol may fight aging, www.nih.gov.
Ozturk, B., & Anli, E. (2014). Different techniques for reducing alcohol levels in wine: A review. In BIO Web of Conferences (Vol. 3, p. 02012). EDP Sciences.