In the early years of enology in the US several enology pioneers worked through protocols and procedures to standardize sensory evaluation of wine to assess the effects of winemaking operations and consumer acceptance^1,2. This approach, known as descriptive sensory analysis, grew into a science that is now widely used by academics to do research on wine chemistry, wine quality, and consumer opinions.

In December of 2020, the Virginia Tech Food Sciences Department, Virginia Tech Cooperative Extension, and the WRE joined forces with funding from the Virginia Wine Board to explore the topic of descriptive analysis and its application to winery and tasting room training in a two-part workshop. The first session featured Dr. Jacob Lahne, a food scientist from Virginia Tech, explaining how descriptive analysis is done in the research laboratory. In case you missed it, following is a link to a recording of his presentation. Tune in for a fascinating deep dive into academic food science with important practical applications for winemakers.

To see Dr. Lahne’s full presentation, click here.

References

(1) Amerine, M. A.; Roessler, E. B.; Filipello, F. Modern Sensory Methods of Evaluating Wine. Hilgardia 1959, 28 (18).
(2) Noble, A. C.; Arnold, R. A.; Masuda, B. M.; Pecore, S. D. Progress Towards a Standardized System of Wine Aroma Terminology. American Journal of Enology and Viticulture 1984, 35 (2), 107–109.

Has it ever happened to you? While evaluating a wine, maybe writing a note for tasting or blending, you encounter an odor. Its familiar. Maybe you know when you have smelled it before, or where the odor comes from, or you can name similar odors…. But you cannot name the odor itself. Its like the word is on the tip of your … nose. The “tip-of-the-nose” phenomenon is actually very common, especially when blind tasting a wine^1,2.

Sensory expertise can be defined as “the ability to discriminate among different aromas, to recognize aromas when cued, and to describe aromas in wine by free recall”^3,4, all skills that are vital when crafting high quality wine. Successful odor identification, according to Cain (1979, quoted in Herz and Engen) includes (1) commonality (2) prolonged odor-name association and (3) supplemental cues. Improving our sensory expertise will mean deliberate practice to name and remember smells.

Why its so hard to remember and name smells

Relative to our other senses, humans are bad at recognizing and naming odors. The overall ability of participants to identify familiar odors in odor recognition research studies is reportd to be less than 50%^1,2. There are several reasons that contribute to this lack. The olfactory epithelium, the portion of the nasal cavity that initially perceives odors, as well as the portions of the brain involved in processing odors, are much smaller in humans than in other mammals². The diversity of odor receptors is also smaller; nearly half of the genes in our genome for odor receptor molecules are non-functional². The way the brain is wired for odor perception bypasses other the processing centers that would force integration with verbal processing, meaning you can perceive and remember an odor without every identifying it with a word. In most human cultures, but not all, the language we have for odors is relatively impoverished with little redundancy. This means there is less reinforcement from multiple experiences, so words for odors are harder to encode in the brain. It also means that once encoded, there is less interference, and therefore is less likely to be forgotten¹.

Figure 1: By Patrick J. Lynch, medical illustrator - Patrick J. Lynch, medical illustratorFile:Head_olfactory_nerve.jpg, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=68370471”

In his webinar, Dr. Lahne talked about the process of training a panel of tasters to improve the reliability of data in academic trials using descriptive sensory analysis. Training of that type is focused on one specific question, takes many people and a lot of time, and is well beyond the scope of what we can or need to do in the winery. But as wine professionals, it is still important that we train our palates to better discriminate among flavors and aromas and recognize faults.

How to improve our sensory expertise

As with most endeavors, the best way to improve our sensory expertise is to practice. In his New York Times bestselling book Outliers: The Story of Success, Malcolm Gladwell⁵ quotes work done by Dr. K. Anders Ericcson looking at what separated those who were merely good and those who had the potential to be great in their field. The common thread seemed to be time on task, with roughly 10,000 hours needed for mastery. In her New York Times bestselling book Grit: the power of passion and perseverance⁶, MacArthur Genius Award winner Angela Duckworth picks up this thread and expands upon it by asking Dr. Ericcson why she, a runner since college (surely clocking more than 10,000 hours) has not become an excellent runner. The professor asked her if, when she was running, she was deliberate in her practice. Did she have a goal? Did she measure her time or log her distance? His point was that achieving excellence is not simply about practice but deliberate practice.

Nobody is suggesting you put in 10,000 hours of sensory training (unless perhaps you plan to sit for your Master Somm exam). However, the idea of deliberate practice is a good take-home for sensory training as well. Many of us have sniffed and swirled a lot of wine in our professional careers. But if we are doing this without any attempt to improve, our sensory skills may be stagnant. A little bit of intentionality may go a long way to honing our palate. In a recent study of sensory training, Lestringent et al³ found that as little as 10 minutes of training on reference standards increased participants ability to describe wine with words. This held true for amateurs, experienced tasters, and even the panel that originally came up with the standards!

Deliberate practice includes goals. What goals should we set for sensory training?

The first goal of sensory training should be to accurately associate odors with their names. When screening participants for a sensory study, Frost and Noble (2002) found no correlation between scores on a wine trivia test and smell association test, meaning wine knowledge does not itself improve sensory performance. When Lestringent et al (2017)⁴ trained panelists on terms and standards correlating to the second tier of the wine aroma wheel (which are fairly general, terms like spicy, citrus, berry), even experienced and trained tasters averaged less than 160/186 possible points. This immediately after training³. Lest you lose heart, experience did help, here. Consumers scored an average of 120/186.

Many terms used for wine are unfamiliar in common vocabulary and can even be cryptic to experienced wine tasters if not defined. The wine aroma wheel includes terms such as sorbate, linalool, and butyric. I only learned what butyric acid smelled like during our sensory workshop at King Family Vineyards in 2019 when Dr. Chang prepared the standard for this compound. When members of my group smelled the standard and discussed its attributes, we agreed it reminded us of parmesan cheese. Based on this shared experience of training with terminology, I now remember both the term and the smell that goes with it.

From: https://www.winecolorado.org/wp-content/uploads/2019/03/Smelling_Wine.png

We cannot achieve a goal of consistently and accurately using terminology unless we know what that term really means. Also, the less familiar an odor is, the less likely we are to be able to find it in our memory¹. Deliberate practice introduces us to these stimuli and reinforces that learning with repetition and experience.

Another goal of sensory training is to become more precise and consistent with our terms in order to better communicate with others. Due to the tremendous variation in human anatomy and experience, sensory analysis is fraught with variation. Sensory perception itself begins with signal reception, which for odor means a volatile chemical binds to a protein receptor. Humans have roughly 340 identified genes for odor receptors, any of which contain variants from individual to individual. Genetic differences also alter the number of taste buds (the structures on which these receptors sit) between individuals. Differences in diet, health and environment can alter the number of taste buds that are active (yes, you can literally burn out taste buds with spicy food!). In addition, sensation is additive, so the other odors that are received at the same time may compete for attention by the neurons. Once odors are received, their presence is communicated though the nervous system to the brain. Some nerves fire more readily than others. Once in the brain, the past experiences of the taster will determine if the odor is recognized and how it is labeled. The same odor in a different mixture may be encoded with very different terminology^1,2,7.

Consensual terms used to describe wines by (1) experienced tasters and (2) trained experienced tasters. From Lestringent et al (2019)

Wine professionals often have a wide experience with odors and flavors, meaning our vocabulary may be very broad. Unfortunately this may lead to the same odor being described with multiple, redundant terms in different circumstances. If one term is used in one situation and a different term in another, it may not be clear the same odor is being referenced. In their comparison of consumers and experienced tasters, Lestringent et al⁴ found experienced tasters used 36 different terms to discriminate the wines while experienced tasters who had been trained with standards required only 10 for the same discrimination (Figure 1). Training meant that people were more likely to use the same words for the same odor. Sensory training is a way of tying a specific odor to a specific memory and a specific word that all tasters have in common, leading to more accurate and precise odor recognition and recall.

Finding common language allows for better communication with others. Winemakers and staff need to be able to recognize faults and name them with common understood terms to be able to properly treat the issues. Common terminology is also vital to participation in the larger conversation of wine. When explaining the origins of the Wine Aroma Wheel, which was developed to provide common terminology for California winemakers, Ann Noble said “How can you evaluate your own wine against others if you don’t use the same words? (CITATION – TEAGUE).

Sensory training on standards can also help winemakers to better diagnose problems and issues in the winery. Many of the differences in descriptors that people use make no difference in the management of the wine, for example the difference between “black” and “red” raspberries. However, some differences may be relevant to winemaking operations. One example is the term “vegetal”. A wine may be described as vegetal because it has perceptible levels of methoxypyrazine, which smells roughly like green bell pepper. However, this same term can be applied to a wine that has mercaptan (cabbage-y) or DMS (cooked/canned green beans or asparagus). Unfortunately each of these potential flaws leads to a different potential treatment of the wine, and what works for one will not work for another. No amount of aeration will remove the methoxypyrazine (though it may affect the thiols and therefore perception of green pepper, but that is a whole other newsletter….). A similar argument could be used for various terms used to describe microbiological odors. During the development of the Brettanomyces aroma wheel, researchers found several terms that were usually associated with Brettanomyces infection could also be due to lactic acid bacterial infection⁸.

References

(1) Herz, R. S.; Engen, T. Odor Memory: Review and Analysis. Psychonomic Bulletin & Review 1996, 3 (3), 300–313.
(2) Jackson, R. S. Wine Science: Principles and Applications, 4 edition.; Academic Press: Amsterdam, 2014.
(3) Bowen, J. T. S.; Cantu, A.; Lestringant, P.; Sokolowsky, M.; Heymann, H. Wine Sensory Reference Standards to Align Wine Tasters on a Shared Terminology. Catalyst: Discovery into Practice 2018, 2 (2), 42–49.
(4) Lestringant, P.; Sela-Bowen, J.; Cantu, A.; Sokolowsky, M.; Heymann, H. Exposure to Aroma Reference Standards Alters Participants’ Descriptions of Commercial Red and White Wines. Catalyst: Discovery into Practice 2019, 3 (1), 17–22.
(5) Gladwell, M. Outliers: The Story of Success; Little, Brown, and Co: New York, New York, 2008.
(6) Duckworth, A. Grit: The Power of Passion and Perseverance; Scribner: New York, 2016.
(7) Urry, L. A.; Cain, M. L.; Wasserman, S. A.; Minorsky, P. V.; Reece, J. B. Campbell Biology (11th Edition); Pearson: New York, 2017.
(8) Joseph, C. M. L.; Albino, E.; Bisson, L. F. Creation and Use of a Brettanomyces Aroma Wheel. Catalyst: Discovery into Practice 2017, 1 (1), 12–20.
(9) Zoecklein, B. Protein Stability Determination in Juice and Wine. Virginia Tech Online Enology Publications 1991.

“The tool that transformed wine tasting”¹, the Wine Aroma Wheel, was developed by Dr. Ann Noble and her colleagues at UC Davis at the request of the Sensory Evaluation Sub-committee of the American Society of Enology and Viticulture in the early 1980’s^1,2.  First developed for academic audiences, by 1990 it had become so popular with wine critics and consumers that laminated versions of The Wine Aroma Wheel were being sold at wine shops and through mail order. (These are still available today, currently listing at about $10 on Amazon.) The Wine Aroma Wheel remains a valuable tool for wine sensory analysis and training, and the story of its development provides an excellent case study in the development of a sensory lexicon.

At the time, people didn’t have good terminology for describing wine. Rather, they tended to use nonspecific terms (“elegant”, “masculine”), leading to difficulties in communication. The Wine Aroma Wheel was developed to aid communication among members of the wine industry including winemakers, marketers, researchers and wine writers, with specific emphasis on communication between winemakers and cellar staff as well as winemaker understanding of the academic literature². As Ann Noble herself said “How can you even evaluate your own wine against others if you don’t use the same words?”¹.

Like any lexicon (a word bank for a particular topic), the Wine Aroma Wheel began with a list of “virtually all possible wine descriptors”¹ compiled from student laboratories, wine critical reviews, published papers, and other sources^1,2. Then the list was refined. Hedonic or subjective terms were removed. An effort was made to include terms that were as specific as possible so that each separately identifiable aroma or flavor was represented by a descriptive term². A questionnaire was sent to over 100 wine professionals to gauge the relevance and potential use of the terms*^1,2. The first version of the wheel was published in 1984 and included a solicitation for readers to comment on the list and make suggestions. Like any good lexicon, it was open to refinement². A second version was published in 1987 and included some re-organization for easier use, elimination of infrequently used or redundant terms and the addition of the “nutty” category. It was at this time standards were also suggested for the terms found in the third tier³. This modified version of The Wine Aroma Wheel remains in common usage.

Several characteristics of the Wine Aroma Wheel make it a useful tool even today. The hierarchical presentation (adopted from wheels already in use for beer and whiskey) organized 119 terms in three tiers to allow similar specific odors to be grouped together under 29 more general categories³. This organizational structure aids in searching for terms, while still allowing more general terms to be used if a more specific term is not appropriate. Second tier terms are often used by wine critics, consumers, and marketing personnel⁴. Though third tier terms are already very specific, they can also be combined (apricot-peach) if needed².

References standards were proposed for each of the third tier terms in 1987³, and standards have now also been formulated for the second tier terms⁵. In both cases, an effort was made to avoid chemicals that are difficult or expensive to purchase, and those that degrade quickly, instead favoring readily available items that can be found at the grocery store (such as fruits and vegetable), winery (oak flavor), or outdoors (cut green grass). Instructions are readily available for standard preparation and include adding foodstuffs or other reference materials to a base of either a neutral wine (free of defects with low intensity aromas) or a blend of water and neutral spirit. After 30 minutes, the aromas should be apparent and useful as references^3,5. Comparison back to the base wine helps detect the effect of a spiked aroma.

Since the publication of the wine aroma wheel, several specialty wheels have also been produced, including wheels for sparkling wine, Brettanomyces, and mouthfeel. Recent studies exploring the effect of training panelists on standards to the second tier of the aroma wheel shows that training leads to better alignment around common terminology, fulfilling the original intent of this project, improving communication among wine professionals.

Reference standards are easy to prepare and use. There are several practical ways you can use these standards during cellar or tasting room training to improve sensory expertise.

*Only 70 of these 100 questionnaires were returned, a good reminder of the importance of responding to inquiries; these folks missed the opportunity to weigh in on what would become the standard terminology of wine. Consider this a friendly reminder to return your Grape Report every year.

References

(1) Teague, L. The Tool That Transformed Wine Tasting. Wall Street Journal. 2020.
(2) Noble, A. C.; Arnold, R. A.; Masuda, B. M.; Pecore, S. D. Progress Towards a Standardized System of Wine Aroma Terminology. American Journal of Enology and Viticulture 1984, 35 (2), 107–109.
(3) Noble, A. C.; Arnold, R. A.; Buechsenstein, J.; Leach, E. J.; Schmidt, J. O. Modification of a Standardized System of Wine Aroma Terminology. American Journal of Enology and Viticulture 1987, 38 (2), 143–146.
(4) Joseph, C. M. L.; Albino, E.; Bisson, L. F. Creation and Use of a Brettanomyces Aroma Wheel. Catalyst: Discovery into Practice 2017, 1 (1), 12–20.
(5) Bowen, J. T. S.; Cantu, A.; Lestringant, P.; Sokolowsky, M.; Heymann, H. Wine Sensory Reference Standards to Align Wine Tasters on a Shared Terminology. Catalyst: Discovery into Practice 2018, 2 (2), 42–49.

Just as we would calibrate a pH meter with buffer solutions before using, it can be helpful to calibrate our palates on a regular basis (a few times per year) or before evaluating wine samples for blending, writing tasting notes, etc. So how would we go about doing this? Here’s some simple steps and tips:

General

• Don’t go it alone. We all have different anosmias (things we are nose-blind to), different numbers and types of odor and taste receptors, different sensory memories, and simply different preferences! Working with a partner or team can help to overcome these biases and reach more consistent results. Plus, sensory training can be a good team building activity!
• Have a “vanilla ice cream” of wine…. Or maybe a whole Neapolitan-esque flight! Again, just as we calibrate the pH meter using 2-3 buffer solutions, it is helpful to have a standard wine (or wines) that are consistently used for tuning up your sensory perceptions and to act as a reference for spiked samples. The best house-reference will a wine that is easily available, free of faults, and a good example of the type of wine you will be evaluating^1,2.
• Gather ingredients for making standards i.e. go grocery shopping! The following recommendations come from “Wine sensory reference standards align wine taster on a shared terminology” by Jennifer Sela Bowen and her colleagues³. These are not set in stone; gather materials that you think will represent the wines you will be using for your training or analysis. You may choose to only make some of these, or focus on one category at a time, then systematically rotating through these 1-2 times per year. For example, focus on fruit and floral in one training session, vegetal and earthy in the next session.

Prepare standards: The idea here is to get the odorants into a form they will easily perceptible during training:

• Chop, crush, slice, toast standards as needed.
• To concentrate and contain aromas, and facilitate multiple people accessing them, it may help to place a quantity (typically a few tsps. to tbsps.) of each standard in a Mason jar with a lid.
• To closer replicate the wine matrix, add 1⁄4 c water and 1⁄2 tsp. vodka or other neutral spirit. You can also use a neutral wine base, free of faults with low aromatic intensity¹. Grocery store box wine is one option.
• As you would with blending formulations, we highly recommend writing down quantity (or percentage) used! This will allow you to replicate your standards from session to session even if you alter the original recipe to better fit your house definition of terms.

After you have prepared your standards, here are a few activities you can do with them:

Activity #1 Use standards to define a set of terms for your in-house wines

1. Define your question. Are you trying to characterize all the aromas in Cabernet Franc? Are you trying to describe what makes one vineyard’s Petit Verdot different than another? With this question, determine which group of wines you will eventually be evaluating.
2. Smell and taste your standard wine(s), and individually generate a complete list of descriptors. This many be your base (“vanilla”) wine or the whole group of wines you wish to characterize, depending on the question you are asking.
3. Compare descriptors with your team to form a large list. 
4. Refine your list:
   • Remove hedonic terms, those that have a value judgement about the wine (great, terrible) and subjective terms, those you could never make a standard for (round, masculine)
   • See if any of the terms could be more specific. If not that is OK, but do ask.
   • See if any of the terms are redundant, with different team members using different words for the same odors. See if you can form a consensus around one term.
   • Grouping similar descriptors together, e.g. raspberry and red berry, may help evaluate specificity and redundancy.
5.  Smell the standards that correlate to your descriptors.
   • If you have a lot of standards, cleansing your nose by smelling coffee beans or even the inside of your arm will refresh your sense of smell.
   • If you have mixed your standards in a base wine (rather than water or spirits), smelling the base wine periodically helps highlight the effect of that odorant on the wine in general.
6. Discuss with your team:
   • How closely does what you smell correlate with the descriptor and the actual odor in the wine? 
   • Are there additional terms that need to be added to your description?
   • Are there additional standards you need to make? How would you make them? (Make these and record the recipe)
   • Do any of your standard formulations need to be tweaked? If so, feel free to make that change, just make sure to write down how to make the improved standard.
   • The goal of this evaluation is not to reach a “right” answer, but to work toward a team consensus about what a given word choice, e.g. red fruit, encompasses and have an in-house reference standard (formulation) that roughly approximates the terminology, e.g. 4 smashed raspberries + 1 canned cherry in ¼ c water. The simple act of putting words and standards to what you are smelling and tasting will help improve your sensory expertise
7. After calibrating with your standard wine(s), repeat Steps 5-8 with the in-house wines which you seek to evaluate.

Other suggested activities:

1. For simple odor recognition activities, The Wine Aroma wheel is a great place to start. The Wine Aroma Wheel website offers a downloadable how-to guide for beginners that would be great to use with beginners or as part of a tasting room experience. These activities can easily be focused around more specific terms for use in training more experienced tasters.
2. In “The University Wine Course”, Marian Baldy shares a number of activities she used to use with her wine appreciation classes at UC Davis. She includes chapters on sensory analysis of white and red wines complete with worksheets. Appendix D includes step by step instructions for setting up these labs at home. They make great training exercises.
3. For more focused work, consult published papers in sensory science for lexicons and standards, then apply them to you own wines. For example, to evaluate your own Viognier, perhaps use the standards found in “Descriptive Analysis and Consumer Study of Viognier Wines from Virginia, France and California”, a study funded by the Wine Board. After you memorize the terms and the reference standards, evaluate your own Viognier and perhaps some from your neighbors. Smelling and tasting your own wine blind in the company of others may give you valuable insights.

*Suggested grocery store standards from Sela Bowen et al (2018)

References

(1) Noble, A. C.; Arnold, R. A.; Masuda, B. M.; Pecore, S. D. Progress Towards a Standardized System of Wine Aroma Terminology. American Journal of Enology and Viticulture 1984, 35 (2), 107–109.
(2) Noble, A. C.; Arnold, R. A.; Buechsenstein, J.; Leach, E. J.; Schmidt, J. O. Modification of a Standardized System of Wine Aroma Terminology. American Journal of Enology and Viticulture 1987, 38 (2), 143–146.
(3) Bowen, J. T. S.; Cantu, A.; Lestringant, P.; Sokolowsky, M.; Heymann, H. Wine Sensory Reference Standards to Align Wine Tasters on a Shared Terminology. Catalyst: Discovery into Practice 2018, 2 (2), 42–49.