Currently, Sangiovese is also the cultivar with the highest number of clones registered in the Italian National Catalogue of Grapevine Cultivars showing 130 clones in 2020. Despite its global distribution and importance, there are a limited number of international studies on Sangiovese grapes and wines. The most substantial scientific works were presented at theInternational Symposium of Sangiovese between 2000 and 2004 in Italy. Some of these studies showed the influence of regionality and terroir on the flavor profile of Sangiovese wine. Recent research has focused on the relationship between Sangiovese clones’ grape quality and their oenological properties and polyphenol composition of Sangiovese wines and the mouthfeel perception. A first study about the chemical characterization and comparison of Sangiovese wines from California and Italy was recently reported. The findings demonstrated that the California Sangiovese wines have common characteristics with the Italian wines, particularly related to some volatile grape-derived compounds. These components can be associated with the varietal character of Sangiovese in both regions as the wines in each region retain a common set of characteristics, particularly for the varietal volatiles that originated from grape. Typical characterization of wines includes relationship between sensory profile and volatile compounds, polyphenols, and elements. A much smaller number of studies have compared the chemical and sensory profiles of wines from multiple countries, including Malbec from Argentina and California, red wines from Australia and China, and Sauvignon blanc wines from France, New Zealand, Spain, South Africa, and the United States. Regional typicality is an important concept for the wine industry as it not only delineates geographic areas but also comprises wines with recognizable sensory characteristics and composition. Characterizing regional differences in wines requires studying the intrinsic quality as its inherent physical-chemical characteristics. Moreover, perceived quality is rated by experts, critics, and consumers, gallon pot which altogether defines a profile that describes common regional characteristics among wines. The concept of perceived quality is even more critical when the studies are related to typical wine such as a Protect Designation of Origin . In fact, in a PDO context or when describing a wine belonging to a particular region and produced with a recognizable grape variety, the intrinsic quality of wines could be summarized by the typicality assessment.
Typicality is defined as the characteristics of a product from a terroir, meaning that the product is representative of its terroir, with terroir defined by two dimensions such as the environmental factors and the variety, cultivation, and wine making practices. Among them, the effect of interactions between the natural environment and the vegetal material is known to be a major driver of wine typicality and quality. Thus, typicality can be defined as a set of properties of belonging and distinction. Considering the absence of defects as a pre-requisite, some authors proposed that the intrinsic quality is the resultant of three different profiles: an eligibility profile, whose parameters are common to all wines ; an identity profile , whose parameters are related to the grape variety and the terroir; a style profile related to the brand, expression of the kind of wine making. The eligibility profile can change over time without affecting the identity of the wine, while the identity profile cannot change because it represents the distinct characteristics that define the typicality of a wine. Finally, the style profile can chance overtime as function of the market or the winery brand needs, without altering the identity profile of the wine. It is important to highlight that even in countries with consolidated protected designation of origin and protected geographical indication systems, a scientific approach of typicality still represents a challenge in terms of concept and sensory methodologies. Since Sangiovese is one of the most wide-spread Italian red grapes and a very terroir-linked variety, it is important to study this grape cultivar on a broader scale in order to answer some key questions such as the relationship between the chemical differences, in terms of eligibility and identity profiles, of the wines from different countries and the sensory profiles of the relevant wines,and how do Tuscan experts perceive the typicality of the Sangiovese wines from California and Italy, and which sensory descriptors best describe the wines. The purpose of this study was to evaluate the intrinsic and perceived quality of Sangiovese wines from Italy and California, defining both similarities among wines from the same region of origin and the main differences between wines from Italy and California.
Twenty commercial wines from the 2017 harvest were collected to be representative of both regions . The selection of the wines was made according to the study of the 2016 vintage by the same authors. All of the wines used in this study were sourced from commercial producers, were required to be 100% Sangiovese, and were not oak barrel aged. All wines selected did not show off-flavors. A minimum of 6 bottles were received for each wine sample. As the wines were made solely from Sangiovese grapes under commercial wine making conditions, the differences in composition should reflect the regional styles. In California, the wines were chosen from the following American Viticultural Areas : Central Coast, North Coast and Inland Valley region. The AVAs incorporate the following counties/regions: Amador County, Napa Valley, Santa Ynez Valley, Paso Robles, Saint Joaquin valley and Alameda County. In Italy, the wines were chosen from Tuscany representing the wine areas of Chianti Classico, Chianti, and Montalcino. As all wines used in this study were commercial products; there was no control over the viticultural or wine making practices, and all participating wineries were asked for a “best representation of Sangiovese. The eligibility chemical characteristics were represented by standard parameters, color indices, and polyphenol composition; the identity chemical characteristics were represented by the volatile fractions of the wines. The style requirement was represented by the chemical variables related to wine aging . The standard parameters were measured with FT-IR analyses according to OIV/OENO Resolution 390/2010 and carried out by means of a FOSS WineScan . Color intensity and hue were measured according to the method of Glories and the total phenols index as described by Ribereau-Gayon. The ultraviolet-visible absorbance of the samples was measured on an Agilent spectrophotometer Cary 8454 UV–visible diode array detector, and the software used was UV–Visible ChemStation . Milli-Q water was used as a reference . The polyphenol contents of the wines was determined according to Girardello et al. methods using an Agilent 1260 Infinity HPLC equipped with an autosampler, temperature-controlled column compartment, and a diode array detector.
The polyphenol composition of the wines is shown in Table S1 . Free volatile compounds were determined according to the method developed previously by HS-SPME GCMS. The analytical system for the determination was a Gerstel MPS2 autosampler mounted to an Agilent 6890N gas chromatograph paired with an Agilent 5975 mass-selective detector constituted the analytical system for the GC-MS analysis. The software used was MSD ChemStation . The volatile composition of the wines is shown in Table S2 . All the wine samples were analyzed in triplicates for all chemical parameters.The descriptive sensory analysis panel took place in the J. Lohr Sensory Room at the Department of Viticulture and Enology, University of California Davis. The panel consisted of 11 judges. We recruited the participants from students, staff, and friends of UC Davis based on availability and interest. The protocol was exempt by the internal regulatory board . The panel leader trained the panelists in six 60-min training sessions. In the first sessions, the panelists were presented with a range of Sangiovese wines and invited to describe them, generating descriptors and idea of standards. In the subsequent sessions, gallon nursery pot the judges were provided of subset of samples and reference standards until they reached the consensus about the attributes and the score sheet sequencing. The references were prepared from food and household products commonly available in the supermarket. The level of training of the panelists was checked by an individual evaluation of a subset of the samples and the analysis of the data. The eligibility sensory profile was described by the following 6 attributes: Sour, Sweet, Bitter, Viscous, Astringent, and Hot/Burning. The identity profile was defined by the following 13 aromatic attributes: Citrus, Floral, Black pepper, Dried fruit, Barnyard, Dark Fruit, Rubber, Cherry, Alcohol, Honey, Red berries, Earthy, and Bell pepper in-mouth flavor. One attribute described the style requirement, namely Oak odor and Oak in-mouth flavor. The wine samples were served at room temperature in black glasses covered with plastic lids. Each sample contained a constant volume of 40 mL of wine. Wines were tasted blind, coded with randomized three-digit numbers, and served twice during the training period. At the end of the training period, the panel had consensus on 14 aromas, 3 taste and 3 mouthfeel descriptors for the wines . The panelists had the opportunity to familiarize themselves with the data entry system FIZZ network for collecting the attribute ratings. Before each evaluation, panelists took an aroma quiz on the consent aromas, and on the first data collection day, panelists tasted the taste and mouthfeel standards. The experimental design consisted of 12 wines served across judges in a balanced block design in triplicate. We labeled the wine samples with different 3-digit codes for each panelist. Panelists evaluated all wines in a total of 6 sessions, where one session consisted of 6 samples. Panelists rated the wines in individual, ventilated, and light isolating tasting booths under white light. For attribute ratings, we used an unstructured 15-cm line scale anchored by the wording “not present” to “very intense”, except for viscous, where the wines were rated from “thin” to “thick”. Judges were required to spit all the wine samples and wait 30 s between samples to clean their palates with water and unsalted crackers. At the end of each session, panelists had snacks, and after the study, panelists received a gift card. All the training and evaluation sessions were performed in about two months .Eleven Italian experts , working with Sangiovese wine, with extensive experience with the different expression of Sangiovese wine produced in most important wine producing Italian areas, were involved in a sensory evaluation session in which three tests were performed: Napping® test and the typicality and color assessments. The same 12 wine samples submitted to the descriptive analysis were evaluated except for the sample 12C that was damaged during shipment from California to Italy. These sensory evaluations took place in the wine sensory laboratory at the Department DAGRI, University of Florence . The expert panelists were informed at the beginning of the study that the wines were all Sangiovese of the 2017 vintage. They were then instructed to assess the color of the samples presented under a white light, in glasses covered with plastic lids, labeled with capital letters, from A to M. The panelists were instructed as follows: “Imagine that you wanted to explain to someone what a Sangiovese wine color is. To explain, you can suggest to this person to evaluate a wine. For each wine presented, you must answer the following question: Do you think that this wine is a good example or a bad example of what a Sangiovese wine color is?” The score of each sample was assigned on a categorical scale, from 1 to 7, anchored at left to “very bad color” and on the right to “excellent color”. After this, judges proceeded to the Napping and typicality assessments. The Napping is a specific variant of Projective Mapping, a method originally proposed for applied sensory studies by Risvik et al. to describe overall differences among samples. In both the Napping and typicality sessions, panelists were presented with the 11 wine samples plus one replicate. The evaluations were performed in isolated, ventilated sensory booths under red lights, to eliminate bias attributed to color differences. Each wine sample consisted of 25 mL of wine at room temperature presented, in clear 190 mL standard tasting glasses covered with plastic lids, and labeled with different random three-digit codes for each panelist and session. For both tests , a complete randomized and balanced experimental design was followed for the presentation order. In the Napping session, the 12 samples were simultaneously presented to the panelists, who were then required to project them on a two-dimensional space , in a way that reflected their perceived sample differences, i.e., by placing samples perceived as similar close to each other, and samples perceived to be more different further apart.