What is one reason wines may taste harsh when enriched with too much sugar?

Wines that are enriched with too much sugar can taste harsh primarily due to insufficient flavors to balance elevated alcohol levels. When sugar is added to a wine, fermentation converts it to alcohol. An increase in alcohol content can enhance the perception of harshness, especially if the wine lacks complementary flavors such as acidity, fruitiness, or tannins.

If the inherent flavors of the wine do not sufficiently balance the increased alcohol, it creates an unappealing taste profile that may be perceived as harsh or even overwhelming. This situation highlights the delicate balance needed in winemaking between sweetness, acidity, tannin structure, and alcohol content to achieve a harmonious flavor profile.

In this context, the other options focus on different aspects. For example, overly sweet notes overpowering tannins might contribute to a different imbalance, while high aldehyde content or lack of fermentation relate to distinct chemical issues in winemaking rather than the specific impact of added sugar on flavor balance.