Evaluation of the intrinsic and perceived quality of sangiovese wines from California and Italy – Science & Wine
by Valentina Canuti Sangiovese is the most cultivated red grape in Italy where it is certified for the production of several Protected Designation of Origin (PDO) wines, and it is one of the most cultivated Italian red grape varieties in California. Despite the worldwide distribution of this variety, there is a lack of international studies […]

by Valentina Canuti

Sangiovese is the most cultivated red grape in Italy where it is certified for the production of several Protected Designation of Origin (PDO) wines, and it is one of the most cultivated Italian red grape varieties in California. Despite the worldwide distribution of this variety, there is a lack of international studies on Sangiovese grapes and wines. This is the main reason that convinced the two groups of researchers from the University of Florence and UCDavis to start a two-year comparison between Sangiovese wines from Italy and California.

Sangiovese wines have been collected from the major wine regions of California and Tuscany, and compared chemically and sensorially in order to highlight the similarities and differences. The results of the first year study (2016 harvest wines) showed that sangiovese from both countries had common characteristics, especially with regard to aromatic compounds derived from grapes, such as vitispiran I, benzaldehyde, β-farnesene, TDN and β-damascenone, meaning that the Sangiovese variety was recognizable despite the different country of production. The second year study (2017 harvest wines) the same chemical characterization was carried over with the sensory analysis of the wines in order to examine the intrinsic quality of the samples, in terms of eligibility (attributes common to all wines such as pH, titratable acidity, alcohol content, volatile acidity, malic acid and residual sugar, color intensity, tint and total phenol index) and identity profiles (attributes that distinguish different territorial identities such as compounds volatiles from grapes and by alcoholic and malolactic fermentations), and how they could reflect on the sensory perception of wines. It was interesting to see how the main differences mainly resulted from the eligibility profile. In fact, California wines had higher alcohol content and pH, but had lower acidity and polyphenol content, reflecting the lighter red color of the wines. In contrast, Italian wines were more colorful due to the higher content of polyphenols and in particular pigmented polymers and monomeric anthocyanins.

Based on the chemical differences in the composition of wines from the two regions, it was then explored how the intrinsic quality, in terms of chemical differences, could be reflected in the sensory eligibility and identity profiles of the wines. Moving on to perceived quality, the second objective of the study was to see how Tuscan wine experts perceived the peculiarity / typicity of Sangiovese wines from Italy and California and to relate the sensory descriptors that could be associated with the typicity of the wines. wines.

Figure 1 shows the sensory profiles of samples of Californian and Italian wines and a real separation between the two regions has not been fully demonstrated except for Italian wines 4I and 5I on the right side of the graph. The wines on the left were described by a range of freshness, for which varietal aromas were noticeable in some samples, while in those on the right, they were masked by aromas typical of a fully developed wine.

Figure 1. Principal component analysis (PCA) scores (a) and loadings (b) plots of eligibility profile (blue) and identity (red) (sensory attributes QDA) for Sangiovese wines from Italy (coded with I) and California (coded with C) from Harvest 2017.

When the Tuscan experts evaluated the wines, the results were different because with the Napping test, the Californian and Italian wines (evaluated globally except for the color) were clearly separated, which proved that the two types of wines were perceived differently for the taste and smell characteristics. Despite this, the results of the typicity assessment did not show the same clear distinction between wines from the two regions (Figure 2) and the average score of all wines was very similar with slightly higher California wines but not significantly different.

Figure 2. Representation of Italian and Californian wines by multiple factor analysis according to the X and Y coordinates of Napping, the quality of the color and the typicity scores provided by the panel of experts. a) Distribution of wines (I: Italy; C: California); (b) distribution of color quality (j1 - j11 in red) and typicity scores (G1 - G11 in blue) (developed as additional data).

This result can be explained by the fact that, even if the experts perceived the differences between the wines, they did not only associate them with the typicity. Considering the extensive training and experience of the experts, the lack of agreement between them can be interpreted not only as a variability of their opinion but also as an indication that from the point of view of the perceived quality in terms of typicality Sangiovese wine, experts considered all wines to be part of the identity profile. At the same time, the distribution of the highest mean scores indicates that typicity was correlated with fruity and floral attributes, unlike the descriptors of pepper, backyard, rubber, and earth (data not shown, from a PLS elaboration). In other words, the typicity of Sangiovese was linked to the perception of varietal characteristics which in this wine were generally linked to the fruity and secondly to the floral.

figure 3. Samples of Californian and Italian wines.

In the case of the color assessment, the experts separated the wines more clearly (Figure 2) and overall Italian wines scored significantly higher. In fact, these samples, reflecting the chemical parameters, had a more intense color and overall a lower tint than the Californians.

Figure 4. Sensory laboratory at UCDavis.

Finally, the results of this study confirm that the perceived quality in terms of typicality of Sangiovese was still linked not only to fruity and floral aromas but also to lightness and freshness, despite the intrinsic qualitative aspect of the "structure" of the. wine and is considered a "good" color. In addition, the results confirm that Sangiovese shows flexibility in terms of chemical and sensory modification, depending on the production area and that it can be considered as typical even if it comes from an area far from traditional areas.

From research papers:

  • Canuti, V., Cantu, A., Picchi, M., Lerno, LA, Tanabe, CK, Zanoni, B., Heymann, H and Ebeler, SE (2020). Assessment of the intrinsic and perceived quality of Sangiovese wines from California and Italy. Foods, 9 (8), 1088.
  • Canuti, V., Frost, S., Lerno, LA, Tanabe, CK, Zweigenbaum, J., Zanoni, B., and Ebeler, SE (2019). Chemical characteristics of Sangiovese wines from California and Italy of the 2016 vintage. Journal of agricultural and food chemistry, 67 (9), 2647-2659.

Valentina canuti, oenologist, PhD. Researcher at the Department of Agricultural, Food, Environmental and Forestry Sciences and Technologies (DAGRI), University of Florence. His research themes focus on the influence of winemaking practices on the composition and quality of wines. This includes studies to determine the influences of different winemaking techniques, the use of coadjuvants for coloring and tartaric stabilization of wines. Sustainability is recently studied as the impact of different vinification protocols in the organic, biodynamic and conventional cellar on the quality of the grape and wine from a chemical and sensory point of view. Most of the research is done on grape and Sangiovese wine.

We would recommend either Wineworks Premium or Wineworks Superior as your first 30 Bottle Kit Wine. Both of these ranges are designed to produce a good quality wine that is ready to drink within 2-4 weeks but will benefit if left up to 6-8 weeks. Furthermore, they also have a great selection of wines to choose from.

If you’ve never made wine before or you simply don’t have any of the equipment or ingredients any longer then you could purchase one of our bundles. These bundles combine all the required equipment along with your prefered wine pack so that you can have everything delivered to your door and just get started. The Wineworks Superior Starter Bundles are a great choice if you want to keep the equipment budget down but still choose the quality of wine you’d like to go for. Whereas, the Wineworks Luxury Starter Bundles offer a better quality equipment pack and still let you choose from a great choice of wine kits.

The two most important critères of making wine are Cleanliness and Temperature. Firstly remember everything that comes into contact with the wine should be cleaned and sterilised ( see below ). Secondly maintain a constant temperature between 21-26°C ( 69-79°F ). It is much better to be on the cool side and constant than hot one minute and cold the next. Airing cupboards are definitely no, no’s. ( See below )

Clean and sterilise all equipment. Here’s a selection of Sterilisers you can use and if you not quite sure which steriliser to go for then you can take a look at our Beginners Wine Making Part 1 - Cleaning, Sterlising

Wineworks Superior wines : These usually take 10-15 days to ferment, and a further week to clear. Again the wine can be drunk immediately but we recommend ageing it 4 weeks but you can leave it up to 12 months. The time you will leave it will depend very much on your stocks. So get plenty built up. The reds benefit more than the whites with ageing. Certain packs ( see the list below ) are suited more to the experienced wine maker and take around 4 weeks to ferment and then left for a further 2 weeks. These products does really benefit from ageing. All the kits we list in this section require little ageing.

As it’s new to you it will probably take in all 2 hours for your first batch. However, once you are used to it 1 hour is about the maximum amount of time needed. We would also point out bar the bottling side; it takes just as long to make 6 bottles as it does to make 30 bottles, so we strongly recommend you make the larger quantity. After all 6 bottles doesn’t go very far as we said before !

From our experience it is much better to maintain a constant temperature than a fluctuating one. We suggest 21-26°C ( 69-79°F ), although if it is cooler than this, it is not a problem, it just takes slightly longer to ferment. If you can’t maintain this then we supply three different forms of heating equipment : Brew Belt / Heat BeltThis is a simple insulated electric cable that wraps round your container and provides a gentle heat. It is very souple and extremely easy to use. Heat Tray ( 4 demi/5 Gallon Fermenter ) This is like a flat tray that provides a gentle continuous heat that goes under the fermenter. Immersion HeaterThis drops into the container, through the bung and can be thermostatically controlled to maintain the juste temperature. Similar to a fish tank heater. All these can be added to our starter kit packages. See our scène showing the genres of heating equipment available for your fermentation.

It is important to clean

If you’ve made it this far, hopefully understanding a bit of what we’ve said, then you’ll want to know how much it will cost to get started ! As you may have noticed, we’ve put together a couple of equipment packs which include everything you need, and take the confusion out of buying. You can make your first 30 bottles of Wine for approximately £65. 00. That’s all in ( Equipment


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