Also known simply as alcohol, or grain alcohol, ethanol is the primary alcohol found in wine. Ethanol is a critical constituent of wine and is produced from sugar during fermentation. The concentration of ethanol in wine can affect taste, microbial activity, the solubility of compounds, and tax rates. Recent times have brought wine's alcohol levels to all-time highs. Even the great wines of the Napa Valley's past stayed in the 12.5%-13.5% range. Wine publications have influenced a "desired style" of higher alcohol wines. The Alcohol and Tobacco Tax and Trade Bureau allows any winery to label its wine within 1.5% of the actual alcohol percentage. Here at Wine Fellas, it is the first thing we analyze, you'll notice lower alcohol percentage allows for more expressive fruit.
Residual Sugar (RS)
Glucose and fructose are natural compounds produced by vines during photosynthesis. In wine, Glucose + Fructose is often synonymous with “Residual Sugar”, measured near or after the end of primary fermentation to evaluate dryness. In conventional winemaking, sugar is also often added to correct brix levels before fermentation or to appeal the consumer's palate. We feature only wines that have been fermented to dryness without chaptalization (added sugar).
Total Sulfur Dioxide (SO2)
Sulfur Dioxide occurs naturally in fermentation (small amounts) but is toxic in heavy amounts. Total sulfur dioxide (SO2) is a measure of both the free and bound forms of SO2. Bound SO2 refers to SO2 molecules that are bonded to other compounds, primarily aldehydes, pyruvate, and anthocyanins. Sulfur Dioxide is usually used throughout all stages of the conventional winemaking process to prevent oxidation and microbial growth, also to control yeast. Excessive amounts of SO2 can inhibit fermentation and cause undesirable sensory effects. There is a small portion of the population that is highly allergic to Sulfur Dioxide, but it also masks aromatics and wine's true character with overuse. Our producers add little to none, we assure this by our analysis. In Europe legal limits (parts per million) for Red wines: 160ppm, White/Rose wines: 210ppm and Sweet wines: 400ppm, US legal limits: 350ppm and Australia 250ppm. Naturally occurring levels of SO2 in wines are usually found around 10-20ppm. At Wine Fellas, you'll find all wines analyzed for low sulfites.
We can learn a lot about a wine from its pH, especially how stable it is. pH is the measure of a solution’s acidity or hydrogen ion concentration. Solutions with low pH values (<7) are acidic, while those with high pH values (>7) are basic. Wine pH values typically fall between 3.0 and 4.0 on the pH scale. However, pH is measured on a logarithmic scale, so a wine with a pH of 3.0 is 10 times more acidic than a wine with a pH of 4.0. pH is a critical constituent of wine, affecting microbial activity, tartrate solubility, the interaction of phenolic compounds, and molecular SO2levels.
Titratable Acidity (TA)
Titratable acidity (TA) measures total available hydrogen ions in solution. This measurement includes both the free hydrogen ions and the undissociated hydrogen ions from acids that can be neutralized by sodium hydroxide. Although generally considered a simple parameter, titratable acidity is actually a reflection of complex interactions between the hydrogen ions, organic acids, organic acid-salts, and cations in solution. Results of this test are reported in terms of Sulfuric Acid, which is the standard reporting convention for TA in the European Union.