UC Davis

We purchased 21 California Petite Sirah wines, all from vintages 2017-2020 and from Lodi, Paso Robles, Napa Valley, Sonoma County, the Sierra Foothills, Mendocino, and California. Price ranges were High (H) more than $40 per 750 mL bottle (5 wines), Medium (M) $20-$40 per bottle (9 wines), and Low (L) less than $20 a bottle (7 wines). A trained panel of 10 judges evaluated each wine in triplicate in a balanced randomized order for 29 sensory attributes. All attributes were anchored with reference standards. Data were analyzed via XLSTAT and RStudio.

Nineteen attributes were significantly different across the wines. Most wines were quite similar with some noted exceptions. These exceptional wines tended to be very high in the following attributes: barnyard, cooked vegetable, earthy, and smoky. The effect of price was only significant for three attributes, namely acetone with the L-wines having the lower acetone scores; sweet with the H-wines being perceived as sweeter; and hot with the H- and M-wines being perceived as hotter. The sweet perception result was not supported by the glucose and fructose concentration of the wines since the L-wines had significantly more of these compounds. It is possible that the perceived sweetness was affected by the floral-fruity aromas in these wines. The hotness results were exactly in line with the alcohol concentration of the wines, and the acetone perception results were in line with the volatile acidity data.

We chose 9 wines for a consumer hedonic study and found significant differences in liking with the wine highest in barnyard odor being by far the least liked. Additionally, the internal preference map showed that the Northern Californian consumers overwhelmingly rejected wines high in the barnyard attribute.