As an expert sommelier and brewer, I can confidently say that wine is not supposed to be sour or bitter. However, it is important to note that different wines can have varying levels of acidity and tannins, which can contribute to these taste sensations.
Let's start with sourness. Sour taste in wine is often associated with high levels of acidity. Acidity is a natural component of wine and is responsible for providing freshness, balance, and structure. When the acidity in a wine is too high, it can create a tart or sour taste sensation on the palate. This can be particularly noticeable in white wines, such as Sauvignon Blanc or Riesling, which are known for their vibrant acidity. However, it's important to remember that acidity is a desirable characteristic in wine when it is well-balanced and complements the overall flavor profile.
On the other hand, bitterness in wine is mainly attributed to the presence of tannins. Tannins are natural compounds found in the skins, stems, and seeds of grapes, and they also come from the wooden barrels used for aging wine. Tannins have a conserving function and contribute to the structure, texture, and aging potential of wine. They can create a drying and slightly bitter sensation on the back part of the tongue. Red wines, particularly those made from grape varieties like Cabernet Sauvignon or Nebbiolo, tend to have higher tannin levels compared to white wines. However, it's important to note that not all red wines are excessively bitter, and the level of bitterness can vary depending on factors such as grape variety, winemaking techniques, and age of the wine.
It's worth mentioning that taste perception can vary from person to person, and what one person may perceive as sour or bitter, another person may find perfectly balanced and enjoyable. This is why wine tasting is such a personal and subjective experience. It's always fascinating to see how different individuals can have varying preferences and perceptions of wine.
To summarize, while wine can contain elements of sourness and bitterness, these characteristics are not supposed to dominate the overall taste profile. A well-made and balanced wine should have acidity that provides freshness and liveliness without being overly sour, and tannins that contribute to structure and complexity without being excessively bitter. Ultimately, finding a wine that suits your personal taste preferences is key, and it can be a delightful journey of exploration and discovery.