August 2014 Volume 9 Number 2 grape and wine composition comes from advances in analytical This issue of the ASEV Technical Update contains interpretive and sensory methods for identifying and quantifying the com- abstracts written by authors of articles published in the first and pounds that contribute to flavor. Therefore, Part 2 of this review second issues of the American Journal of Enology and Viticulture, 2014. A link to the online Journal article appears at the end of provides an overview of the chemical and sensory analysis ap- each abstract. proaches that have been used to deconstruct wine flavor into its component parts with an aim toward relating the chemical com- position to the unique sensory properties that are associated with different wine varieties and styles. Origins of Grape and Wine Aroma. Part 1. Chemical Components and Viticultural Impacts Am. J. Enol. Vitic. 65:25-42 (2014) Anthony L. Robinson,1,2 Paul K. Boss,3 Peter S. Solomon,4 1 5 N, P, and K Supply to Pinot noir Grapevines: Robert D. Trengove, Hildegarde Heymann, and Impact on Berry Phenolics and Free Amino Acids Susan E. Ebeler5* 1 1 2 1Separation Science and Metabolomics Laboratory, Murdoch University, R. Paul Schreiner, * Carolyn F. Scagel, and Jungmin Lee Murdoch, WA 6150, Australia; 2Treasury Wine Estates, P.O. Box 396, 1USDA-ARS, Horticultural Crops Research Laboratory, 3420 NW Nuriootpa, SA 5355, Australia; 3CSIRO Plant Industry, P.O. Box 350, Orchard Ave., Corvallis, OR 97330; and 2USDA-ARS, Horticultural Glen Osmond, SA 5064, Australia; 4Plant Science Division, Research Crops Research Laboratory Worksite, 29603 U of I Ln., Parma, ID School of Biology, Australian National University, Canberra, ACT 0200, 83660. *Corresponding author ([email protected]) Australia; and 5Department of Viticulture and Enology, University of Cal- ifornia, Davis, CA 95616. *Corresponding author ([email protected]) The composition of Pinot noir berries on grapevines grown with varying nutrient (nitrogen, phosphorus, and potassium) supply Wine is an ancient beverage and has been prized throughout time was investigated in a pot-in-pot, sand culture vineyard. Vines for its unique and pleasing flavor. Wine flavor arises from a mix- were managed to minimize differences in vine water status and ture of hundreds of chemical components interacting with our shading of fruit so that indirect effects on berry chemistry could sense organs, producing a neural response that is processed in the be largely eliminated. Vines grown under reduced nitrogen sup- brain and resulting in a psychophysical percept that we readily ply had lower levels of amino acids and YANs, but higher levels describe as “wine.” The chemical components of wine are derived of some phenolics. Results show that reducing nitrogen supply from multiple sources; during fermentation grape flavor compo- can improve berry color (anthocyanins), but this positive effect nents are extracted into the wine and new compounds are formed on berry composition did not occur until crop yield and berry by numerous chemical and biochemical processes. In this review YAN were greatly depressed. An increase in berry tannins and we discuss the various classes of chemical compounds in grapes phenolic acids under low N supply, however, may be possible and wines and the chemical and biochemical processes that influ- before yield is significantly reduced. ence their formation and concentrations. The overall aim is to Am. J. Enol. Vitic. 65:43-49 (2014) highlight the current state of knowledge in the area of grape and wine aroma chemistry. Use of Production Practices and Sensory Am. J. Enol. Vitic. 65:1-24 (2014) Attributes to Characterize Loire Valley Red Wines Marie Thiollet-Scholtus,1* Soline Caillé,2 Alain Samson,3 Origins of Grape and Wine Aroma. Part 2. Jean-Jacques Lambert,4 and René Morlat1 Chemical and Sensory Analysis 1INRA, UE1117 Vigne et Vin, UMT Vinitera, 49070 Beaucouzé, France; 2 1,2 3 4 INRA, UMR1083 Sciences pour l’Œnologie, 34060 Montpellier, France; Anthony L. Robinson, Paul K. Boss, Peter S. Solomon, 3INRA, UE999 Pech-Rouge, 11430 Gruissan, France; and 4Department 1 5 Robert D. Trengove, Hildegarde Heymann, and of Viticulture and Enology, University of California, Davis, Robert Mon- 5 Susan E. Ebeler * (author affiliations as above) davi Institute, 595 Hilgard Lane, Davis, CA 95616. *Corresponding au- Part 1 of this review summarized the current state of knowledge thor ([email protected]) with respect to the chemical compounds contributing to grape Quality wines are typically the product of soil, climate, and and wine aroma. Much of our understanding of the chemistry of wine production practices. Sensory attributes are increasingly ASEV Technical Update is a publication for ASEV mem bers providing practical research to the wine and grape industries. The content is peer edited, but not peer reviewed. Please direct your feedback, requests for specific content and mini-reviews, questions for Q&A, submissions, and any permis- sions or duplication requests to the AJEV managing editor ([email protected]). ASEV is not responsible for statements or opinions printed herein; they represent the views of the authors and are not binding on the ASEV as a whole. Copyright © 2014 by American Society for Enology and Viticulture. All rights reserved. 1 used to distinguish among protected designation of origin ing from colder climates, paradoxically making these genotypes (PDO) wines. Since 2010, the International Organization of more vulnerable to spring frost in warmer environments. The Vine and Wine has taken all such parameters into account in an model should be useful in climate change modeling to predict official definition of terroir. However, links between production cold acclimation and deacclimation responses of different geno- practices and sensory attributes in geographically circumscribed types under variable climate change scenarios. It may also be used PDO areas had not been investigated until now. Production as a risk-management tool for site selection in regions with un- practices and sensory attributes of distinct PDO wines within known grapegrowing potential and for vineyard management in the same area were assessed. The production practices of pro- regions where cold damage is common. Using temperature data ducers of 33 commercial PDO wines from the Loire Valley, from automated weather stations, the model automatically pro- France, were surveyed, including vineyard training systems, vides local and daily simulated lethal temperatures for the grape viticulture, harvest timing, winemaking, and aging practices. cultivars reported in this study. Coupled with a weather forecast- Descriptive sensory analysis was conducted to characterize the ing service, the model may be used as an early warning system for significant sensory attributes of these same wines. PDO wines impending and potentially damaging cold-temperature events. were separated from one another by classical statistical analy- Supplemented with additional, static information on how to re- ses. About 25% of the analyzed production practices and less spond to cold damage, this forms a decision support system for than 50% of the analyzed sensory attributes could differentiate risk assessment and damage mitigation in grapes. PDO wines produced in the same area: percentage of Cabernet Am. J. Enol. Vitic. 65:59-71 (2014) franc, time of leaf removal, harvest date, yield, duration of fermentation, duration of aging and use of oak, color intensity, viscosity, cloudiness, blackcurrant, prune, spicy, moldy, animal, A High-Resolution Cumulative Degree bitterness, and astringency. Relationships between some produc- Day-Based Model to Simulate Phenological tion practices and sensory attributes were identified. Results Development of Grapevine demonstrate that, under similar climatic conditions and soil Daniel Molitor,1* Jürgen Junk,1 Danièle Evers,1 characteristics, production practices and sensory attributes can Lucien Hoffmann,1 and Marco Beyer1 distinguish PDO wines in well-defined geographic areas. 1Centre de Recherche Public–Gabriel Lippmann, Department Environ- Am. J. Enol. Vitic. 65:50-58 (2014) ment and Agro-Biotechnologies (EVA), 41, rue du Brill, L-4422 Belvaux, Luxembourg. *Corresponding author ([email protected]) Common cumulative degree day models used to forecast grape Modeling Dormant Bud Cold Hardiness growth stages often are only of local validity, restricted to a lim- and Budbreak in Twenty-Three Vitis Genotypes ited number of phenological stages, or do not take into consid- Reveals Variation by Region of Origin eration that the forcing effect of temperature is limited at higher John C. Ferguson,1,2,3 Michelle M. Moyer,1 Lynn J. Mills,1 temperatures. A new model was developed to simulate all 26 Gerrit Hoogenboom,2 and Markus Keller1* phenological stages (according to the BBCH scheme; Biologische 1Department of Horticulture, Irrigated Agriculture Research and Exten- Bundesanstalt, Bundessortenamt und Chemische Industrie) of sion Center, Washington State University, Prosser, WA 99350; 2AgWeath- Vitis vinifera L. Müller-Thurgau between budburst and harvest. erNet, Washington State University, Prosser, WA 99350; and 3present address: 23244 Lower Terrace, Eagle River, AK 99577. *Corresponding Sixty time series of grape phenology from four European coun- author ([email protected]) tries were used to set up and validate the model. Three cumula- tive degree day models (starting with budburst: BBCH 09) with Cold injury is a key environmental