TY - JOUR T1 - In-Line Measurement of Color and Total Phenolics during Red Wine Fermentations Using a Light-Emitting Diode Sensor JF - American Journal of Enology and Viticulture JO - Am. J. Enol. Vitic. SP - 463 LP - 470 DO - 10.5344/ajev.2014.14023 VL - 65 IS - 4 AU - Nicholas L. Shrake AU - Rajeevan Amirtharajah AU - Charles Brenneman AU - Roger Boulton AU - André Knoesen Y1 - 2014/12/01 UR - http://www.ajevonline.org/content/65/4/463.abstract N2 - An in-line color and total phenolic sensor is described to track the color and total phenol evolution during red wine fermentations. The sensor uses multiple light-emitting diodes (LEDs) spanning the ultraviolet and visible spectrum, in particular 280 and 525 nm. The performance of phenolic sensor was evaluated by analyzing fermentation samples collected from multiple red wine fermentations performed during the 2012 season. The study confirmed that the LED phenolic sensor measurements strongly correlate with measurements performed with a reference UV-vis spectrophotometer and that in-line measurements can be made in a practical manner after removal of yeast and pulp with a 2.0 μm filter. The use of a 100 μm path-length flow cell avoids the need for dilution, making in-line measurements possible. The sensor provides in-line measurement on the evolution of the total phenolic content and color extraction patterns during red wine fermentations. ER -