Throughout this investigation, we explored how sugar influences the rate of fermentation and how this, in turn, affects the overall quality of the wine. Three wines were produced, each with different sugar levels. The investigation was designed so that a wine had a fairly low sugar content; one had an ideal sugar content and the other a high sugar content. After stopping the fermentation process, a taste test was conducted to evaluate the quality of the wine. The tasters were blindfolded to reduce the possibility of biased opinions. Each taster tried not only each wine, but also sugar water and tonic water. This allowed us to evaluate the validity of the results. It was found that most of the conclusions drawn by the tasters were legitimate. During the fermentation process, the yeasts initially added to the wine reproduce, through asexual reproduction. Theoretical research concluded that this depends on the sugar content of the wine. The higher the sugar content of the wine, the higher the reproduction rate. When yeasts are exposed to anaerobic conditions, the yeast is able to undergo fermentation, the process by which grape juice becomes alcoholic. Energy is essential for this process. The necessary energy required is produced through anaerobic respiration. Glucose + Oxygen  Carbon dioxide + Water + Energy C6H1206 + O2  CO2 + H20 + Energy Figure 11: equation for anaerobic respiration Unknown Author, 2010 Therefore the greater the quantity of sugar (glucose- C6H1206) introduced into the wine, the greater the the energy it can produce. This energy produced is transferred to the yeasts, providing the necessary energy…… half of the paper…… concentration as it may have generated the highest concentration of tartaric acid, while Wines B and C may have produced other acids present in the wine, such as l malic, lactic, citric, acetic or succinic acid. Esters are compounds formed by condensation between an acid and an alcohol. In the Investigation the ethanol present in the wine would have provided the alcohol and the acids present would have produced the acidic component, therefore it was expected that the tasting would have provided for the detection of some esters. During taste testing, many tasters described the wine as having fruity flavors, detecting esters such as apple, peach in wines A and B. Apple ester is a common ester that is detected in alcoholic beverages when ethyl acid is present. Therefore wines A and B may have had a higher concentration of ethyl acid than wine C.