Lab Report : Tannin Concentration ( Experiment A )

Determining Total Phenolic Content of Grape Juice using Visible Spectrophotometry Formal Food Analysis Laboratory Report February 7, 2013 By Carla Reed Lab partner: Nina Jung Total Phenolic Content of Grape Juice using Visible Spectrophotometry Abstract The health benefits of red wine are well known and consumption has been encouraged more over the years because of the populations increasing obesity rates and the inherent complications thereof; including coronary heart disease and

certain level of alcohol that subsequently becomes toxic to the yeast thus killing them (Smith, D. 2009). Once fermentation is over, many wines may display signs of turbidity or cloudiness. This is due to suspended particulates such as proteins, tannins, phenols or dead yeast cells that cause haziness in wine when not removed. These particles can precipitate out of the wine naturally under the influence of gravity however this is a lengthy process and those that want fast results rely on chemical