TY - JOUR T1 - High Alcohol Wine Production from Grape Juice Concentrates JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 345 LP - 351 DO - 10.5344/ajev.2001.52.4.345 VL - 52 IS - 4 AU - W. A. Buescher AU - C. E. Siler AU - J. R. Morris AU - R. T. Threlfall AU - G. L. Main AU - G. C. Cone Y1 - 2001/01/01 UR - http://www.ajevonline.org/content/52/4/345.abstract N2 - Improved fermentation methods for grape juice concentrates could allow fermentation of high alcohol wines from concentrate, which may eliminate brandy fortification, provide an easier process to produce dessert wines, and prevent stuck fermentations. Two studies to determine fermentation conditions for the production of high alcohol wine from grape juice concentrates were conducted. The yeast strain in both studies was Saccharomyces cerevisiae L2226. Wines were fermented in flasks on an orbital shaker to increase fermentation rate and keep the yeast cells suspended. Study 1 investigated the production of high alcohol wine from concentrates of four varietals (Chardonnay, Chenin blanc, Rubired, and Sauvignon blanc) reconstituted from 68 to 35 °Brix, inoculated with different yeast levels (4 x 106 or 17 x 106 cells/mL), and with nutrients (Fermaid or diammonium phosphate) added alone or in combination. Treatments containing the highest inoculation level and nutrients resulted in the highest alcohol content. The highest alcohol level (18.15%) was achieved using Sauvignon blanc concentrate inoculated with 17 x 106 cells/mL yeast and 2 g/ L each of Fermaid and diammonium phosphate. Study 2 examined aeration (0, 0 to 48, and 30 to 48 hr), nutrient addition method (at the start or in increments), and fermentation of 20 °Brix juice with supplementation of concentrate during fermentation versus starting the fermentation at 35 °Brix. High alcohol wines (over 20%) were made by fermentation of grape juice concentrate. Moderate aeration of fermenting juice resulted in higher alcohol levels than treatments that were not aerated. The addition of nutrients in increments resulted in lower alcohol concentrations than treatments with nutrients added at the start of fermentation. The addition of concentrate during fermentation decreased production of alcohol compared to fermentation at 35 °Brix. The highest mean alcohol level (20.96%) was produced from 35 °Brix juice aerated 0 to 48 hr with nutrients added at the start of fermentation.Acknowledgments: Partial support for this research was provided by Lallemand. Published with the approval of the Director, Arkansas Agricultural Experiment Station. ER -