Which statement describes primary fermentation?

Which statement describes primary fermentation?

• A. Secondary fermentation converts sugars to alcohol and CO2.
• B. Malolactic fermentation converts malic acid to lactic acid.
• C. Primary fermentation converts malic acid to lactic acid.
• D. Primary fermentation converts sugars to alcohol and CO2.

Answer: (D)

Primary fermentation is the stage when yeast consumes the sugars in the must and converts them into alcohol and carbon dioxide. This is the main transformation that turns a sugary grape must into wine, with CO2 released as gas as fermentation proceeds. The sugars yeast targets include glucose and fructose in the must, and the process continues until sugars are depleted or alcohol levels become inhibitory. Malolactic fermentation, which follows primary, involves bacteria converting malic acid to lactic acid to soften acidity and alter flavors, so it’s not part of the primary stage. A secondary bottle fermentation can occur in sparkling wine production, but that’s a separate step from the primary fermentation. Therefore, the statement that describes primary fermentation is that sugars are converted to alcohol and CO2.

Primary fermentation is the stage when yeast consumes the sugars in the must and converts them into alcohol and carbon dioxide. This is the main transformation that turns a sugary grape must into wine, with CO2 released as gas as fermentation proceeds. The sugars yeast targets include glucose and fructose in the must, and the process continues until sugars are depleted or alcohol levels become inhibitory. Malolactic fermentation, which follows primary, involves bacteria converting malic acid to lactic acid to soften acidity and alter flavors, so it’s not part of the primary stage. A secondary bottle fermentation can occur in sparkling wine production, but that’s a separate step from the primary fermentation. Therefore, the statement that describes primary fermentation is that sugars are converted to alcohol and CO2.