This essay was tough and I definitely didn’t have enough facts and understanding to the recommended 60 minutes. I definitely don’t understand this material and I guess I have to (**gulp**) teach it in order to understand it better. This essay is a mess.
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The author tells us a lot about “old-fashioned” methods of measuring grape ripeness, such as measuring sugar levels and acidity. And yet the “postmodern” way of assessing maturity takes many other considerations into the equation. Make a list of the old-fashioned benchmarks and another list of the postmodern benchmarks for grape maturity. After making your lists, compare and contrast the two lists as the topic for a 60-minute timed essay practice.
Measures of ripeness – Old fashioned
- Sugar
- Total acidity
- pH
- browning of seeds/softness of skin
Measure of ripeness – Postmodern
- Phenolics/anthocyanins
- Reductive/antioxidative strength
The old-fashioned ways of looking at ripeness were developed before sophisticated understanding of oxidative and reductive chemistry was understood.
Sugar has been historically used to measure for ripeness because it is easy to measure and there is a predictable relationship between sugar and final alcohol content of the wine. This measurement is less relevant today as, in some regions of the world, sugar can be adjusted before fermentation and in other parts of the world, sugar ripeness is achieved before phenolics and flavors have developed, so this is a less relevant measurement.
Total acidity is usually also measured historically, but different tannins impact your mouth in different ways, so a more relevant measure would be a measurement of the different types of acids (malic, acetic, etc.). Again, acidity can be adjusted before and after fermentation. While these adjustments are not ideal, ripeness measurements based on total acidity is less relevant.
Using pH as a measure of ripeness is starting to bridge the transition from old fashioned to postmodern. pH is a measure of free protons whereas total acidity measures all acidic protons (free and bound). The measure of pH is important in order to understand the effectiveness of SO2 (higher pH means more SO2 is needed and vice versa), understand color stability (less color at high pH), stability of tartrates (which can cause a haze; less stable at higher pH), and microbial stability (less stable at higher pH). Given the resources and time a winemaker has, pH is an essential measurement of ripeness, although again, this can be adjusted prior to the start of fermentation (though this is not ideal).
The last old-fashioned measurement of ripeness is to just taste the fruit! As fruit matures, the skins will soften and the seeds will brown and lignify, so while these are subjective measures, these are some of the building blocks to the ultimate texture of the wine, and is a less sophisticated way of measuring phenolics of the grapes.
The postmodern view looks at a wine’s phenolics in order to build a structure for the aromatics of a wine to reside. In the presence of oxygen, one type of phenolic, tannins, will chain together, consume the oxygen, and increase their reductive strength. They will replicate and form longer polymers. This reductive strength measures a wine’s vigor and longevity, and must be matched with the winemakers’ intended style and shelf life. Anthocyanins is a type of phenolic that will bookend the tannins polymer chains (created as the tannins consume oxygen). Shorter polymers will give a softer mouthfeel.
Measuring reductive strength, its anti-oxidative strength, is a measure of vigor and longevity to the wine. Knowing how much oxygen a wine can consume over the course of its life can tell a winemaker about the shelf life of their wine and the winemaker should match the style of wine to its reductive strength.
While the old-fashioned methods are still being taught and are essential in a winery without the equipment or means to accurately measure elements like phenolics, winemakers are just starting to better understand the role of phenolics and oxygen in determining the wine’s longevity, and these postmodern tools may become just as common as the old fashioned measurements in the future.
