A Vertical Wine Tasting is when wines are sampled based on their vintage year. This is an excellent way to compare a single wine type of a producer over various years. Make sure you have the same varietal (or blend), the same producer and then sample all of the various vintages/years.
Varietal or Blend: Chardonnay and Seyval
Vintage: 2014, 2015, 2016
Therefore a vertical wine tasting could be done using three wines:
Newman Chardonnay/Seyval Blend 2014
Newman Chardonnay/Seyval Blend 2015
Newman Chardonnay/Seyval Blend 2016
Note: For your Vertical Wine Tasting you can choose any number of vintages and they don’t have to be sequential.
I am going to try and break this down to what I feel you should be looking at given your experience with wine tastings.
Normally with Vertical Wine tastings, the primary goal is to try to pick out the vintage. The older wines will likely be mellower; the younger wines sharper. Old reds will be more ruby in colour; younger reds more vibrant in colour. If this is the first Vertical Wine Tasting you have done, I would really try to focus here. Try to think of everything else as constant and just try to pick out the year.
The next more advanced factor to often analyze is to think back to that growing season. This will be easier if you are drinking a local wine as you can think back to the weather at the time. If not, you will have to do a bit of research on that region. For instance, was the summer colder than usual one season? That wine might therefore be more acidic than the others. Was there a lot of rainfall one year? This will result in more plump berries and therefore the wine might be lighter in characteristics. Was the growing season very hot one year? This will result in small berries with high sugar concentrations likely resulting in a superior quality vintage.
If you can easily pick out the year in your vertical wine tasting and relate it back to the environmental factors of that growing season then you are well on your way to owning a winery!
The final thing to look at is to look at the winemaker. (Although please be nice on us!) With wine there is a human element into making wine. Let’s go back to looking at a year where the growing season was particularly rainy. The winemaker is stuck with a whole bunch of big plump berries with little to no substance in the juice. The winemaker is therefore going to look at a way to fill out this wine. The winemaker for instance might oak more heavily than normally in order to try and balance out the lighter wine. Also, in most areas, a pure varietal wine only has to be 75% of the grape on the label. If you see Chardonnay on the label, it only has to be 75% or more Chardonnay grapes. Some years it might be 75%, some years it might be 100%. The winemaker can therefore blend at a small scale to try to balance out imperfections in the juice.
What I am getting at is that just because the wine is the same producer with the same grape varietals it does not mean that everything else was constant! Hope this helps, most important of all is to have fun with your Vertical Wine Tasting!