The Effects of Pulsed Electric Field (PEF) on the Polyphenol Content and Maceration of Idaho-Grown Sangiovese Grapes

Idaho has a fast-growing wine industry with an economic impact of $314.1 million. With this economic growth, interest in treatments to produce better red wines is of high interest. Sangiovese grapes are not as red or pigmented when compared to other red grapes like Cabernet Sauvignon, so they are not as commonly chosen. Pulsed Electric Field (PEF) is an emerging treatment shown to increase the extraction of polyphenols and expedite the maceration process for wines. Polyphenols affect the color, taste, and aroma of red wines. This research aims to measure the polyphenol extraction over a 7-day maceration period and determine the ideal PEF treatment for Sangiovese grapes. An untreated control sample was compared to three PEF treatments (low, medium, and high) that varied in field strength and specific energy levels. On day 3, the polyphenol concentration for the control increased by 48.3%, while the medium PEF treatment at 74.4% was the largest increase observed. With this increase, the maceration period could be decreased to 3 days. With the use of PEF in Idaho wineries, red wines like Sangiovese, can be produced with a more appealing color and a quicker maceration period, increasing the overall production.