Source: UNIVERSITY OF CALIFORNIA, DAVIS submitted to
PROFILING GRAPE AND WINE AROMAS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1004941
Grant No.
(N/A)
Project No.
CA-D-VIT-6013-H
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Nov 6, 2014
Project End Date
Sep 30, 2019
Grant Year
(N/A)
Project Director
Ebeler, S.
Recipient Organization
UNIVERSITY OF CALIFORNIA, DAVIS
410 MRAK HALL
DAVIS,CA 95616-8671
Performing Department
Viticulture and Enology
Non Technical Summary
There is increasing interest in metabolic profiling to measure a wide range of metabolites in plant and animal systems. By focusing on the volatile metabolites, particularly those that may contribute to flavor, an aroma profile can be obtained. Hundreds of compounds can contribute individually to food and beverage flavor however, it is still unclear how these compounds interact with each other in complex mixtures to influence sensory perception. For example, work in our laboratory has shown that while 3-isobutyl-2-methoxy pyrazine concentrations alone are often directly correlated with perception of vegetal aromas in Cabernet, the presence of other compounds, particularly those with fruity aromas, can mask vegetal perception, even when pyrazines are present. Therefore there is increasing need for analytical profiling methods that will quickly, reproducibly, and simultaneously measure not just individual flavor compounds, but many volatile compounds from a range of chemical classes. In addition, many aroma compounds exist in grapes as nonvolatile precursors that do not directly contribute to aroma. Upon acid or enzymatic hydrolysis of the precursors, such as occurs after crushing and during fermentation and storage, the free aroma compounds are released and can contribute to grape and wine aromas. Using a rapid method recently developed in my laboratory we can now profile these bound volatiles in order to better predict the "potential" aroma value of grapes. We propose to use these tools to evaluate composition of aroma volatiles and their precursors in order to evaluate effects of viticulture and winemaking practices on grape and wine aroma.
Animal Health Component
0%
Research Effort Categories
Basic
30%
Applied
60%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5025010200050%
5031131200050%
Knowledge Area
503 - Quality Maintenance in Storing and Marketing Food Products; 502 - New and Improved Food Products;

Subject Of Investigation
1131 - Wine grapes; 5010 - Food;

Field Of Science
2000 - Chemistry;
Goals / Objectives
The goals of this project are to:(1) Develop approaches for rapid and sensitive profiling of volatile aroma compounds in grapes, wines and other foods;(2) Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods;(3) Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines and foods;(4) Relate chemical composition of grapes, wines, and foods to sensory properties.
Project Methods
Aroma is one of the most important factors determining wine character and quality (Ebeler and Noble, 2000). However, there are limited chemical assays with clear connections to sensory attributes (Chapman et al. 2005). In addition, there have been few studies linking aroma composition in grapes to the final aroma composition in the wine (Chapman et al. 2005). These limitations are due, in part, to the lack of analytical methods that allow for rapid screening or profiling of multiple volatile compounds that are present at a wide range of concentrations in both grapes and wines.(1) In the proposed studies we will use headspace solid phase microextraction (HS-SPME) to profile the free volatile compounds in grapes and wines (Canuti et al. 2009). These methods have previously been used to identify volatile compounds in Cabernet Sauvignon and Merlot wines that relate to the sensory profiles (Hjelmeland et al. 2013; King et al. 2014). We have also used the method to begin to obtain information on changes in free volatile compounds in grapes as a function of grape maturity (Canuti et al., 2009) and winemaking practices (Callejon et al. 2012). We will continue to improve these methods to increase the number of compounds that can be measured through the use of authentic standards to confirm and identify unknown compounds. In addition, we will use new mass spectral (MS) approaches, including tandem MS to improve sensitivity for targeted analytes (Hjelmeland et al. 2012). We propose to apply these approaches to understanding the role of a variety of viticultural and winemaking practices on the volatile composition and aroma properties of the grapes and wines.(2) Glycosidically bound aroma precursors will be measured in grapes and wines using the recently developed method of Hampel et al. (2014). Direct enzymatic hydrolysis of grape and wine samples, and comparison of volatiles before and after hydrolyis, will be used to measure 'aroma potential' of grapes and wines samples and to monitor effects of viticulture and winemaking practices on the glycosidically bound precursors in grapes and wines.(3) We will use gas chromatography-recomposition olfactometry (GC-R) approach that we recently developed to understand the perception of complex aroma mixtures such as occur in grapes, wines and foods (Johnson et al. 2012). In this approach a GC is modified with a switch and then a cold trap in-line between the capillary column and the mass spectrometer and the olfactory detector. Individual compounds or groups of compounds can be eliminated and or recombined in the cold-trap and subsequently smelled at the olfactory port to create a series of in-instrument recomposition and omission mixtures. We can now use this approach to characterize the contribution of individual compounds and/or groups of compounds on the aroma quality of volatile mixtures obtained from foods and beverages.References:Canuti, V., Conversano, M., Li Calzi, M., Heymann, H., Matthews, M. A., Ebeler, S. E. 2009. Headspace solid-phase microextraction-gas chromatography-mass spectrometry for profiling free volatile compounds in Cabernet Sauvignon grapes and wines. J. Chrom. A., 1216: 3012-3022.Chapman, D. M., Roby, G., Ebeler, S. E., Guinard, J-X., and Matthews, M. A. 2005. Sensory attributes of Cabernet Sauvignon wines made from vines with different water status. Australian Journal of Grape and Wine Research 11: 339-347.Ebeler, S. E. and A. C. Noble. 2000. Past and the future: Bucket flavor chemistry to senso-chemistry. Proceedings of the ASEV 50th Anniversary Meeting, Seattle, Washington. Am. J. Enol. Vitic., 51(5): 205-208.Hampel, D., Robinson, A. L., Johnson, A. J., Ebeler, S. E. 2014. Direct hydrolysis and analysis of glycosidically-bound aroma compounds in grapes and wines: Comparison of hydrolysis conditions and sample preparation methods. Austr. J. Grape Wine Res. In Press.Hjelmeland, A. K., Collins, T. S., Miles, J. L., Wylie, P. L., Mitchell, A. E., Ebeler, S. E. 2012. High throughput, sub ng/L analysis of haloanisoles in wines using HS-SPME with GC-triple quadrupole MS. Am. J. Enol. Vitic. 63: 494-499.Hjelmeland, A. K., King, E. S., Ebeler, S. E., Heymann, H. 2013. Characterizing the chemical and sensory profiles of U.S. Cabernet Sauvignon wines and blends. Am. J. Enol. Vitic., 64: 169-179.Johnson, A., G. Hirson, S. E. Ebeler. 2012. Perceptual characterization and analysis of aroma mixtures using gas chromatography recomposition-olfactometry. PLoS One. 7(9): e42693. DOI: 10.1371/journal.pone.0042693.King, E. S., M. Stoumen, F. Buscema, A. K. Hjelmeland, S. E. Ebeler, H. Heymann, R. B. Boulton. 2014. Regional sensory and chemical characteristics of Malbec wines from Mendoza and California. Food Chem. 143: 256-267.

Progress 11/06/14 to 09/30/19

Outputs
Target Audience:The target audience includes: national and international scientific researchers in the area of food, beverage, and wine flavor chemistry; professionals in the food and wine industry Some specific audiences reached include the following: I gave a webinar intended for food scientists, analytical chemists and government regulatory scientists on analytical approaches for authenticate food and wine in November 2018. In February 2019, I gave an invited keynote lecture on flavor chemistry of grapes and wines to the Society of Flavor Chemists in Anaheim CA. I gave an invited keynote lecture on grape and wine flavor to winemakers and wine scientists at the American Society of Enology and Viticulture Annual meeting in June 2019. I provided a keynote lecture on grape and wine flavor to Italian food scientists in September 2019. I provided flavor chemistry information for 'A Moment of Science' podcast which is used by many National Public Radio stations and has broad, diverse general public audience. I was on a panel discussion about careers and academic pathways attended by undergraduate students at UC Davis. In fall 2018, I presented information on agriculture majors and careers to high school students from northern CA at the Nevada County Fairgrounds Speaker Series. I was an invited professor in the Erasmus Mundus VINTAGE International Master of Science program in Cessena, Italy, November, 2015; I gave a series of lectures on grape and wine flavor to students in the program. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two visiting scientists from Israel worked in the laboratory to evaluate the phenolic composition of grapes. Three PhD students are working on aspects of flavor chemistry and analysis that are related to this project. Two PhD students completed their dissertations and an MS student completed his thesis. A post-doctoral scholar was trained on UHPLC-qTOF MS analysis of nonvolatile metabolites in grapes/wines. Visiting scientists from Chile worked in the laboratory and were trained on applications for flavor analysis using GC-MS and HPLC-MS methods. A visiting scientist from Italy completed research on Italian and Californian Sangiovese wines. How have the results been disseminated to communities of interest?Results from research on smoke taint-related volatile-phenol glycosides, terpenyl-glysosides, and characterization of volatile profiles in Sangiovese wines, were presented at the 70th Annual Meeting of the American Society of Viticulture and Enology in June 2019. Research results were presented to the Society of Flavor Chemists in January 2019. Results of this work were presented at the National Meeting of the American Chemical Society in New Orleans (March 2018) and the National Meeting of the American Oil Chemists Society in Minneapolis (May 2018). Prof. Ebeler gave a keynote presentation at the Sacramento Section of the American Chemical Society and the San Joaquin Valley Chapter of Sigma Xi (April 2018). Results of this work were presented at the National Meeting of the American Chemical Society in New Orleans (March 2018) and the National Meeting of the American Oil Chemists Society in Minneapolis (May 2018). I gave a keynote presentation at the Sacramento Section of the American Chemical Society and the San Joaquin Valley Chapter of Sigma Xi. In 2016-17, results were presented at the National Meeting of the American Chemical Society (Washington DC and San Francisco), the American Society of Enology and Viticulture (Bellvue Washington), and the Current Wine and Winegrape Research Symposium (held at UC Davis). In 2015-16, results were reported at National Meetings of the American Chemical Society and the American Society of Enology and Viticulture. What do you plan to do during the next reporting period to accomplish the goals?We are completing a second year of a study on the impacts of yeast strain on the release of volatiles from nonvolatile glycosidic precursors. The fermentations have been completed and analysis of volatiles and the nonvolatile glycosides is underway. Data analysis will be completed to combine and compare results from the 2018 and 2019 harvest years.

Impacts
What was accomplished under these goals? Goal 1. Develop approaches for rapid and sensitive profiling of volatile aroma compounds in grapes, wines, and other foods. We continue to develop methods for the analysis of volatiles released from flavor precursors during fermentation. We continue to develop methods to measure partitioning of aroma volatiles in phospholipid micellar solutions. We developed GC-MS methods for analysis of volatile aroma compounds in whiskey and bitters, Rhodendron, and citrus. We developed GC-MS methods for measuring volatiles in oak barrels used to store wines and used the information to assess variability in composition as a function of toasting processes. Goal 2. Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods. We developed a new method, using UHPLC-qTOF MS for identifying and quantifying smoke taint-related volatile-phenol glycoside in wines. We developed a method for measuring proanthocyanidins in wines using UHPLC-qTOF MS. We developed a novel UHPLC-qTOF MS method to profile glycosidically-bound precursors of monoterpene aroma compounds in grapes. Goal 3. Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines, and foods. We compared volatile and nonvolatile profiles from Sangiovese wines from California and Italy to develop models that can be used to characterize and authenticate wines from these two countries/regions. Using a newly developed UHPLC-qTOF MS method, we monitored changes in monoterpenyl glycoside compounds in three grape cultivars harvested at different maturity levels. We evaluated effects of fungal pathogens on volatile emissions from plants, including Rhododendron; a paper was published and work is continuing with funding by USDA APHIS. Goal 4.Relate chemical composition of grapes, wines, and foods to sensory properties. We used GC-Recomposition Olfactometry (GC-R) to relate the chemical composition of Angostura bitters to the sensory properties. Using GC-R, one or more compounds can be eliminated from the aroma mixture and the resulting impact on sensory aroma qualities an be monitored. Work is in progress to evaluate sensory properties of Sangiovese wines from California and Italy. I co-authored a book on sensory and chemical analysis of alcoholic beverages (2017). In a collaborative project we related quality assessments, such as the State Fair Wine Competition and the medals received, to wine composition and sensory properties (2014-15).

Publications

  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Canuti, V., S. C. Frost, L. A. Lerno, C. K. Tanabe, J. Zweigenbaum, B. Zanoni, S. E. Ebeler. 2019. Chemical characteristics of Sangiovese wines from California and Italy of 2016 vintage. J. Agric. Food Chem., 67: 2647-2659. DOI: 10.1021/acs.jafc.8b05674. https://pubs.acs.org/doi/full/10.1021/acs.jafc.9b00634
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Caffrey, A., L. Lerno, A. Rumbaugh, R. Girardello, J. Zweigenbaum, A. Oberholster, S. E. Ebeler. 2019. Changes in smoke-taint volatile-phenol glycosides in wildfire smoke-exposed Cabernet Sauvignon grapes through winemaking. Am. J. Enol. Vitic. 70(4): 373-381. DOI: 10.5344/ajev.2019.19001. https://www.ajevonline.org/content/70/4/373
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Johnson, A., A. Hjelmeland, H. Heymann, S. E. Ebeler. 2019. GC-Recomposition-Olfactometry (GC-R) and multivariate study of three terpenoid compounds in the aroma profile of Angostura bitters. Scientific Reports, 9: 7633. https://doi.org/10.1038/s41598-019-44064-y Open Access https://rdcu.be/bDvDn
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Godshaw, J., A. K. Hjelmeland, J. Zweigenbaum, S. E. Ebeler. 2019. Changes in glycosylation patterns of monoterpenes during grape berry maturation in six cultivars of Vitis vinifera. Food Chemistry, 297: 124921. https://doi.org/10.1016/j.foodchem.2019.05.195


Progress 10/01/17 to 09/30/18

Outputs
Target Audience:I provided flavor chemistry information for 'A Moment of Science' podcast which is used by many National Public Radio stations and has broad, diverse general public audience. I was on a panel discussion about careers and academic pathways attended by undergraduate students at UC Davis. I presented information on agriculture majors and careers to high school students from northern CA at the Nevada County Fairgrounds Speaker Series. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?A visiting scientist from Italy worked in the laboratory to evaluate flavor properties and Italian and California wines. A visiting scientist from Israel worked in the laboratory to evaluate proanthocyanidin composition of table grapes; this is part of a BARD funded project. Three PhD students are working in the laboratory on aspects of flavor chemistry and analysis related to this project. How have the results been disseminated to communities of interest?Results of this work were presented at the National Meeting of the American Chemical Society in New Orleans (March 2018) and the National Meeting of the American Oil Chemists Society in Minneapolis (May 2018). I gave a keynote presentation at the Sacramento Section of the American Chemical Society and the San Joaquin Valley Chapter of Sigma Xi. What do you plan to do during the next reporting period to accomplish the goals?We have completed fermentation of grapes to evaluate impact of yeast strains on release of volatiles from nonvolatile glycosidic precursors. Analysis of volatiles and the nonvolatile glycosides is underway.

Impacts
What was accomplished under these goals? Goal 1. Develop approaches for rapid and sensitive profiling of volatile aroma compounds in grapes, wines, and other foods. We are developing methods for the analysis of volatiles released from flavor precursors during fermentation; work is still in progress. We developed methods to measure partitioning of aroma volatiles in phospholipid micellar solutions; work was presented at various scientific meetings. Partitioning behavior in the micelles was dependent on phospholipid structure and solution temperature. Goal 2. Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods. We developed a method for measuring proanthocyanidins in wines using UHPLC-qTOF MS; work was published. Goal 3. Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines, and foods. We compared volatile composition of wines from Italy and California; work is still in progress. We showed that volatile composition differed depending on geographic origin, but some basic similarities were also observed regardless of country of origin. We evaluated effects of fungal pathogen on volatile emissions from plants, including Rhododendron; a paper was published and work is continuing with funding by USDA APHIS. Goal 4. Relate chemical composition of grapes, wines, and foods to sensory properties. We have evaluated sensory properties of wines from Italy and California and will link sensory properties to volatile chemical composition; work is underway.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: McCartney, M. M., T. V, Roubtsova, M. S. Yamaguchi, T. Kasuga, S. E. Ebeler, C. E. Davis, R. M. Bostock. 2018. Effects of Phytophthora ramorum on volatile organic compound emissions of Rhododendron using gas chromatography-mass spectrometry. Analytical and Bioanalytical Chemistry, 410(5): 1475-1487. Doi: 10.1007/s00216-017-0789-5.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Frost, S. C., J. W. Blackman, A. K. Hjelmeland, S. E. Ebeler, H. Heymann. 2018. Extended maceration and cap management impacts on the phenolic, volatile, and sensory profile of Merlot wine. Am. J. Enol. Vitic. Published online May 29, 2018. DOI: 10.5344/ajev.2018.17062.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Frost, S., L. A. Lerno, J. Zweigenbaum, H. Heymann, S. E. Ebeler. 2018. Characterization of red wine proanthocyanidins using a putative proanthocyanidin database, amide hydrophilic interaction liquid chromatography (HILIC), and time-of-flight mass spectrometry. Molecules 23(10): 2687. https://doi.org/10.3390/molecules23102687 (open access).


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Project results have been reported to industry scientists, academic researchers in the field, and the general public through interviews with reporters/journalists. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?An MS student completed his thesis. A post-doctoral scholar was trained on UHPLC-qTOF MS analysis of nonvolatile metabolites in grapes/wines. A new PhD student has started working in the laboratory and is being trained in GC-MS and UHPLC-qTOF MS methods. Visiting scientists from Chile have worked in the laboratory and been trained on applications for flavor analysis using GC-MS and HPLC-MS methods. How have the results been disseminated to communities of interest?Results have been presentated at the National Meeting of the American Chemical Society (Washington DC and San Francisco), the American Society of Enology and Viticulture (Bellvue Washington), and the Current Wine and Winegrape Research Symposium (held at UC Davis) What do you plan to do during the next reporting period to accomplish the goals?We are monitoring volatiles released from nonvolatile glycosidic precursors during winegrape fermentation and relating the precursor content to the volatile aroma. We continue to collaborate with viticulture colleagues to study the effects of vine diseases on plant metabolites.

Impacts
What was accomplished under these goals? Goal 1. Develop approaches for rapid and sensitive profiling of volaitle aroma compounds in grapes, wines, and other foods. We developed GC-MS methods for analysis of volatile aroma compounds in whiskey and bitters, Rhodendron, and citrus. Goal 2. Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods. We developed a UHPLC-qTOF MS method for profiling glycosidically bound aroma compounds during grape fermentations. We developed a targeted UHPLC-MS/MS method to measure phenolics in diseased grapes and tissues. Goal 3. Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines, and foods. We have shown that red blotch disease changes the phenolic metabolism of grapes. We have shown that phytophthora alters the volatile composition of Rhododendron. We have shown that alteration of methionine-gamma-lyase expression alters production of sulfur volatiles in citrus. Goal 4. Relate chemical composition of grapes, wines, and foods to sensory properties. We have shown that the skin contact and maceration regimes impact the astringency and bitterness of wine and we are in the process of measuring phenolic content of these wines. We have shown that the chemical and sensory properties of whiskey change with the addition of bitters and that qualitative and quantitative changes in the aroma occur depending on the composition of the whiskey/bitters blends.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Frost, S., Blackman, J., Ebeler, S. E., Heymann, H. 2016. Analysis of temporal dominance of sensation data using correspondence analysis on Merlot wine with differing post-fermentation maceration regimes. J. Food Quality and Preference. In Press. DOI: 10.1016/j.foodqual.2016.11.011
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Blanco-Ulate, B., H. Hopfer, R. Figueroa-Balderas, Z. Ye, R. M. Rivero, A. Albacete, F. P�rez-Alfocea, R. Koyama, M. M. Anderson, R. J. Smith, S. E. Ebeler, D. Cantu. 2017. Red blotch disease alters grape berry development and metabolism by interfering with the transcriptional and hormonal regulation of ripening. J. Exp. Bot. 68(5): 1225-1238. DOI: https://doi.org/10.1093/jxb/erw506
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Johnson, A. J., Hopfer, H., Heymann, H., Ebeler, S. E. 2017. Aroma perception and chemistry of bitters in whiskey matrices: Modeling the Old-Fashioned. Chemosensory Perception 10(4): 135-148. DOI: 10.1007/s12078-017-9229-3
  • Type: Journal Articles Status: Accepted Year Published: 2017 Citation: Castillo, E., F. Martinelli, F. Negre-Zakharov, S. E. Ebeler, T. R. Buzo, M. V. McKenry, A. M. Dandekar. 2017. Effects of transgenic expression of Brevibacterium linens methionine-gamma-lyase (MGL) on accumulation of Tylenchulus semipenetrans and key amino acid contents in Carrizo citrange. Plant Molecular Biology. Accepted.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: McCartney, M. M., T. V, Roubtsova, M. S. Yamaguchi, T. Kasuga, S. E. Ebeler, C. E. Davis, R. M. Bostock. 2017. Effects of Phytophthora ramorum on volatile organic compound emissions of Rhododendron using gas chromatography-mass spectrometry. Analytical and Bioanalytical Chemistry. Doi: 10.1007/s00216-017-0789-5. Available online 15 December 2017.
  • Type: Theses/Dissertations Status: Submitted Year Published: 2017 Citation: Godshaw, J. 2017. Applications of mass spectrometric profiling methods for grape, juice, and wine analysis. MS Thesis, UC Davis, Davis, CA. completed September 2017


Progress 10/01/15 to 09/30/16

Outputs
Target Audience:The target audience includes: national and international scientific researchers in the area of food, beverage, and wine flavor chemistry; professionals in the food and wine industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?PhD students trained. Post-doctoral scholars trained. How have the results been disseminated to communities of interest?Yes, results have been reported at National Meetings of the American Chemical Society and the American Society of Enology and Viticulture. What do you plan to do during the next reporting period to accomplish the goals?We continue to apply the GC-MS/MS and UHPLC-qTOF MS methods to monitor volatiles and nonvolatiles in grapes and wines. We are collaborating with a viticulturist to study effects of vine disease on plant metabolites.

Impacts
What was accomplished under these goals? Goal 1. Develop approaches for rapid and sensitive profiling of volatile aroma compounds in grapes, wines and other foods. We developed GC-MS/MS methods for analysis of aroma compounds in grapes/wines and rice kernals. Goal 2. Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods. In a previous year we developed a novel UHPLC-qTOF MS method for profiling glycosidically bound aroma compounds in grapes. Work is underway to expand the number of compounds identified and to apply the method to wines. We are also monitoring phenolics using a similar method. We also developed a method to measure arsenic in wines. Goal 3. Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines and foods. We have shown that volatile, nonvolatile, and elemental composition of grapes and wines can be influenced by growing region, maturity, and winemaking processes. Goal 4. Relate chemical composition of grapes, wines, and foods to sensory properties. I co-authored a book on sensory and chemical analysis of alcoholic beverages.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Walker, G. A., A. Hjelmeland, N. A. Bokulich, D. A. Mills, S. E. Ebeler, L. F. Bisson. 2016. Impact of the [GAR+] prion on fermentation and bacterial community composition with Saccharomyces cerevisiae UCD 932. Am. J. Enol. Vitic. 67: 296-307. DOI: 10.5344/ajev.2016.15092
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Tanabe, C. K., H. Hopfer, G. Gilleland, A. Liba, S. E. Ebeler, J. Nelson. 2016. Total arsenic analysis in Californian wines with hydride generation-microwave plasma-atomic emission spectroscopy (HG-MP-AES). J. An. At. Spectrom. 31: 1223-1227. DOI: 10.1039/C6JA00051G.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hopfer, H., Jodari, F., Negre-Zakharov, F., Whylie, P. L., Ebeler, S. E. 2016. HS-SPME-GC-MS/MS method for the rapid and sensitive quantitation of 2-acetyl-1-pyrroline in single rice kernels. J. Agric. Food Chem. 64(20): 4114-4120. DOI: 10.1021/acs.jafc.6b00703
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Bokulich, N., Collins, T., Masarweh, C., Allen, G., Heymann, H, Ebeler, S. E., Mills, D. A. 2016. Associations among wine grape microbiome, metabolome, and fermentation behavior suggest microbial contribution to regional wine characteristics. mBio, 7(3), mBio00631-16. doi: 10.1128/mBio.00631-16. Open access: http://mbio.asm.org/content/7/3/e00631-16
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hendrickson, D. A.; Lerno, L. A., Hjelmeland, A. K., Ebeler, S. E., Heymann, H., Hopfer, H., Block, K. L., Brenneman, C. A., Oberholster, A. 2016. Impact of mechanical harvesting and optical berry sorting on grape and wine composition. Am. J. Enol. Vitic. 67: 385-397. Doi: 10.5344/ajev.2016.14132
  • Type: Books Status: Published Year Published: 2016 Citation: Heymann, H., Ebeler, S. E. 2017. Sensory and Instrumental Evaluation of Alcoholic Beverages. http://dx.doi.org/10.1016/B978-0-12-802727-1.00005-3, Academic Press/Elsevier, London, UK. ISBN: 978-0-12-802727-
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hjelmeland, A. K., P. Wylie, S. E. Ebeler. 2016. A comparison of sorptive extraction techniques coupled to a new quantitative, sensitive, high throughput GC-MS/MS method for methoxypyrazine analysis in wine. Talanta 148: 336-345. Doi: http://dx.doi.org/10.1016/j.talanta.2015.10.086


Progress 11/06/14 to 09/30/15

Outputs
Target Audience:The target audience includes: national and international scientific researchers in the area of food, beverage, and wine flavor chemistry; professionals in the food and wine industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?PhD students trained. How have the results been disseminated to communities of interest?Yes, results have been reported at National Meetings of the American Chemical Society, the American Society of Enology and Viticulture. What do you plan to do during the next reporting period to accomplish the goals?We are continuing work on the analysis of nonvolatile glycosides using UHPLC-qTOF MS. We are also completing work on a GC-MS/MS method for rapid, trace analysis of methoxypyrazines that contribute to vegetative characters in grapes and wines.

Impacts
What was accomplished under these goals? Goal 1. Develop approaches for rapid and sensitive profiling of volatile aroma compounds in grapes, wines and other foods. Accomplishments: We developed GC-MS methods for measuring volatiles in oak barrels used to store wines and used the information to assess variability in composition as a function of toasting processes. Goal 2. Develop approaches for measuring and identifying nonvolatile precursors of aroma compounds in grapes, wines and foods. Accomplishments: We developed a novel UHPLC-qTOF MS method to profile glycosidically-bound precursors of monoterpene aroma compounds in grapes. We also used elemental profiling methods (e.g., ICP-MS) to measure the elemental composition of wines. Goal 3. Use approaches in (1) and (2) to evaluate effects of viticulture (agricultural) and winemaking (processing) practices on volatile and nonvolatile composition of grapes, wines and foods. We have shown that volatile, nonvolatile, and elemental composition of grapes and wines can be influenced by growing region, maturity, and winemaking processes. Goal 4. Relate chemical composition of grapes, wines, and foods to sensory properties. In a collaborative project we have related quality assessments, such as the State Fair Wine Competition and the medals received, to wine composition and sensory properties.

Publications

  • Type: Book Chapters Status: Published Year Published: 2015 Citation: Ebeler, S. E. 2015. Analysis of grapes and wines: An overview of new approaches and analytical tools. In: Advances in Wine Research. ACS Symposium Series No. 1203. S. E. Ebeler, G. Sacks, S. Vidal, and P. Winterhalter, Eds., American Chemical Society, Washington DC. Pp. 3-12. DOI: 10.1021/bk-2015-1203.ch001
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Hjelmeland, A. K., and S. E. Ebeler. 2015. Glycosidically bound volatile aroma compounds in grapes and wine: A review. Am. J. Enol. Vitic. 66: 1-11. Doi: 10.5344/ajev.2014.14014
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Collins, T. S., Miles, J. L., Boulton, R. B., Ebeler, S. E. 2015. Targeted volatile composition of oak wood samples taken during toasting at a commercial cooperage. Tetrahedron, 71: 2971-2982. DOI: 10.1016/j.tet.2015.02.079
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Nelson, J., H. Hopfer, G. Gilleland, R. B. Boulton, S. E. Ebeler. 2015. Elemental profiling of Malbec wines under controlled winemaking conditions by microwave plasma atomic emission spectroscopy. Am. J. Enol. Vitic. 66(3): 373-378. Doi: 10.5344/ajev.2015.14120
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Hopfer, H., J. Nelson, S. E. Ebeler, H. Heymann. 2015. Correlating wine quality indicators to chemical and sensory measurements. Molecules 20(5): 8453-8483. Doi: 10.3390/molecules20058453 (open-access)
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Hjelmeland, A. K., J. Zweigenbaum, S. E. Ebeler. 2015. Profiling monoterpenol glycoconjugation in Vitis vinifera L. cv. Muscat of Alexandria using a novel putative compound database approach, high resolution mass spectrometry and collision induced dissociation fragmentation analysis. Anal. Chim. Acta. 887: 138-147. Doi: 20.1016/jaca.2015.06.026.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Blanco-Ulate, B., Amrine, K. C. H., Collins, T. S., Rivero, R. M., Vicente, A. R., Morales-Cruz, A., Doyle, C. L., Ye, Z., Allen, G., Heymann, H., Ebeler, S. E., Cantu, D. 2015. Developmental and metabolic plasticity of white-skinned grape berries in response to Botrytis cinerea during noble rot. Plant Physiology Published on-line October 2015, doi: http://dx.doi.org/10.1104/pp.15.00852.