Recipient Organization
CORNELL UNIVERSITY
(N/A)
ITHACA,NY 14853
Performing Department
Food Science
Non Technical Summary
Since red hybrid grapes can more consistently grow well in NY wine regions, palatable red wines produced from hybrid grapes would allow wineries to offer quality red wines each year, with less worry about variable, often harsh, weather conditions, certain grapevine pests, and other challenges to vinifera grape production. Carbonic maceration (CM) is one technique for producing red wines. CM is the process by which grape berries ferment internally under anaerobic conditions prior to yeast fermentation. Studies describe CM wines as exhibiting earlier maturation, having a special odor character and a less dominant varietal character. The special odor character has been described as cherry/berry and spice. Research has shown that CM wines have quantitatively higher concentrations of aromatic esters compared to control wines. Esters were formed as secondary metabolites during intracellular fermentation. Since less varietal character is an outcome of carbonic maceration, and many wine drinkers dislike the flavor characteristics of hybrid grapes, a wine produced from hybrid grapes with less varietal character could be an attractive product. A scientific study of the flavor effects of this winemaking technique in hybrid red wine production is needed. Some NYS winemakers use partial carbonic maceration with some hybrid red varieties, but results are varied and evaluation is difficult without controlled studies. Information about chemical changes and sensory effects of CM versus skin maceration techniques in the production of red hybrid grape wines still needs to be generated, using controlled winemaking techniques, good analytical tools, and controlled sensory evaluation panels. The Beaujolais region of France built global recognition with carbonic maceration of Gamay grapes. Described as the "very antithesis of the intense barrel matured reds" in the Oxford Companion to Wine, CM wines provide the option for consumption of red wine with young, lighter, fruitier and drinkable character. The NYS wine industry may be able to earn similar recognition for their use of unique grape varieties by producing a palatable red hybrid wine option in tasting rooms, wine stores, and restaurants. Wines of this style have the added benefit of quick turnover, from grapes to finished and ready for sale, which frees up fermentation tank and bottled wine storage space in wineries. This saves wineries money. This study will use red hybrid grape varieties associated with, and often developed in, NYS. Grapes will be fermented under controlled conditions, using CM and skin maceration procedures. Traditional Beaujolais wines will be compared with the hybrid CM wines, also, to identify similarities and differences between these popular nouveau wines from France and the red hybrids produced in the study. Chemical and sensory analyses will describe the differences and generate flavor terms for red hybrid CM wines, to begin to develop a regional identity for these wines.
Animal Health Component
90%
Research Effort Categories
Basic
10%
Applied
90%
Developmental
(N/A)
Goals / Objectives
Study will explore vinification techniques for utilizing hybrid wine grapes to consistently produce red wines attractive to consumers. Red wines produced from hybrid grapes, using 2 different maceration techniques, will be compared. Wines will be evaluated by both chemical and objective sensory analyses. Using these results, we will describe the flavor impact of carbonic maceration on red hybrid wines and characterize carbonic maceration effects as desirable or not. We will generate flavor terms for red hybrid CM wines, to begin to develop a regional identity for these wines. Results will be shared with NYS winemakers, to provide good protocols to wineries for producing an additional wine style using hybrid red grapes. Improving red hybrid wine flavor will result in improved wine quality, higher bottle prices, and improved returns to the grower/winery. Survey results will demonstrate whether winemakers think CM is an economically beneficial addition to their winemaking practices.
Project Methods
This study will use red hybrid grape varieties grown and, in some cases, developed in NYS. Grapes will be fermented under controlled conditions, using carbonic maceration (CM) and skin maceration procedures. Carbonic maceration is a wine making procedure with whole grape clusters held in a carbon dioxide environment, so that grape enzymes begin the fermentation process, instead of yeast undertaking fermentation at the start of the process. Using skin maceration technique, grapes are detemmed and crushed. The skins, seeds and juice are in contact while yeast ferment the grape sugars. Students in a Enology course at Cornell University will ferment each grape variety using carbonic maceration and skin maceration. Each fermentation condition will be performed in duplicate. Students will produce wines through the bottling step, and analyze wines as they are produced. Traditional Beaujolais wines, fermented using carbonic maceration, will be compared with the hybrid CM wines, also, to identify similarities and differences between these popular nouveau wines from France and the red hybrids produced in the study. Grape varieties in the study include older and newer hybrids, with potential application of results for wineries interested in promoting these wines. Wines produced for this study will be evaluated by both chemical and objective sensory analyses. Chemical and sensory analyses will describe the differences and generate flavor terms for red hybrid CM wines, to begin to develop a regional identity for these wines. Sensory analyses will be conducted by a trained taste panel, to generate descriptors and begin to characterize hybrid red wines produced via CM, and by wine industry taste panels. Using chemical and sensory analyses' results, we will be able to describe the flavor impact of carbonic maceration on red hybrid wines, compared to skin maceration, and characterize carbonic maceration effects as desirable or not. Specific chemical analyses include residual sugars, pH and titratable acidity, and malic acid, ethanol, total phenolics, and particular ester concentrations. The second fall of the project, commercial wineries will also complete carbonic maceration trials with red hybrid grapes, to evaluate procedures and results in an industry setting.