What Does It Mean When Tannins Are High?

December 5, 2025 •

4 min read

Tannins are astringent plant compounds found in many foods and beverages, including wine, tea, and dark chocolate. For enthusiasts and consumers, understanding what does it mean when tannins are high is crucial for deciphering a product's body, texture, and aging potential.

Quick Summary

A high tannin level imparts a dry, bitter, or astringent mouthfeel and adds body and structure to foods and beverages like red wine. The concentration is influenced by the plant source, ripeness, and processing methods used during production.

Key Points

Astringency: High tannins cause a dry, puckering sensation by binding with saliva proteins.
Structure: They provide a robust body and structure to beverages, especially red wines.
Aging Potential: High tannin levels enable certain wines to age for decades, softening and becoming more complex over time.
Origin: Tannins in wine come from grape skins, seeds, stems, and oak barrels.
Food Pairing: Tannic beverages are often paired with rich, fatty foods to balance the flavor profile.
Sources: Beyond wine, tannins are found in black tea, nuts, dark chocolate, and unripe fruits.

The Science Behind High Tannins

Tannins are a class of polyphenolic biomolecules naturally found in the seeds, skins, and stems of plants, as well as in wood. Their primary function in nature is to serve as a defense mechanism, discouraging animals from eating unripe fruit by making it taste bitter and astringent. On a molecular level, tannins achieve this by binding to and precipitating proteins. This is the very same reaction that causes the distinctive dry, puckering sensation in your mouth when you consume a high-tannin product. The higher the concentration of these molecules, the more pronounced this astringent effect will be.

The Role of Tannins in Wine

When it comes to wine, particularly red wine, high tannin levels are a hallmark of specific styles and varieties. Winemakers can influence tannin extraction by controlling the length of 'maceration,' or the time the grape juice spends in contact with the skins, seeds, and stems. Aging wine in new oak barrels can also introduce wood-derived tannins, adding flavor complexity.

Common high-tannin wines include:

Cabernet Sauvignon
Nebbiolo
Tannat
Syrah/Shiraz
Bordeaux blends
Traditional Sangiovese

How to Identify High Tannins in Wine

Identifying high tannins is a sensory experience that combines taste and mouthfeel. It's not just about flavor; it's about texture. While a low-tannin wine might feel soft and smooth on the palate, a high-tannin wine will have a firmer, more intense, and structured texture.

Astringency: This is the most telling sign. You'll feel a drying, slightly rough sensation on your gums, tongue, and the inside of your cheeks. The higher the tannins, the more intense and persistent this sensation will be.
Bitterness: While not always present, a distinct bitterness can accompany the astringency, especially in young wines with 'green' or unripe tannins.
Body and Structure: Tannins contribute to a wine's 'body' or 'structure'. High-tannin wines often feel heavier and more full-bodied in the mouth.

Tannins in Other Foods and Beverages

Beyond wine, high levels of tannins are responsible for the characteristic flavors and sensations in many other parts of our diet. Knowing these sources can help you better understand and appreciate the impact of tannins.

Black Tea: The strong, bracing, and slightly drying effect of black tea is due to its high tannin content. The longer it steeps, the more tannins are released, increasing its bitterness and astringency.
Dark Chocolate: Unsweetened or high-cacao chocolate contains polyphenols, including tannins, which contribute to its characteristic bitterness.
Nuts: Walnuts, almonds, and other nuts, especially with the skins on, contain tannins that add a dry, slightly bitter element.
Legumes: Red beans and lentils contain tannins that can affect their digestibility and flavor.

The Effect on Aging and Food Pairing

High tannin content is a key factor for the aging potential of certain red wines. The initial harshness of tannins in young wine mellows over time as the tannin molecules polymerize, or join together into longer chains. This process results in a smoother, more refined mouthfeel and allows the wine's complex flavors to develop over decades.

When it comes to food pairing, the astringency of high-tannin beverages is not a flaw but a feature. The tannins bind with the proteins and fats in food, which softens the tannins and enhances the flavor of both the food and the drink. This is why a rich, fatty marbled steak is a classic pairing for a bold Cabernet Sauvignon.

High Tannin vs. Low Tannin


Characteristic	High Tannin	Low Tannin
Mouthfeel	Dry, astringent, textured, puckering	Smooth, silky, softer, less textured
Body	Full-bodied, robust, heavy	Light-bodied, delicate, softer
Aging Potential	High, develops complexity over time	Low to moderate, best consumed young
Texture	Gritty, firm, intense	Gentle, rounded, integrated
Taste	Can be bitter, structured, complex	Often fruit-forward, softer, less aggressive
Food Pairing	Rich, fatty, protein-heavy foods	Lighter fare, poultry, fish, cheeses

Conclusion: Embracing the Astringency

Ultimately, understanding what high tannins mean helps you appreciate the full spectrum of sensory experiences in your food and drink. They are not inherently good or bad, but rather a structural component that defines character. In a young, bold red wine, they contribute a firm, grippy texture that signals aging potential. In black tea, they provide the bracing backbone that complements milk and sugar. By learning to identify and appreciate the presence of high tannins, you can better navigate your preferences and make more informed choices, whether selecting a fine bottle for your cellar or simply brewing a cup of tea. For a deep dive into how wine tannins specifically behave over time, Wine Folly offers an excellent resource.

Frequently Asked Questions

The primary sign is a dry, astringent, and puckering sensation on the tongue and gums, similar to drinking strong black tea.

In moderate amounts, tannins are not bad and can even act as antioxidants. However, excessive consumption can cause stomach irritation or headaches in sensitive individuals.

High tannins act as a natural preservative and antioxidant, allowing certain wines to age and develop complexity for many years as the tannins soften and mellow over time.

The proteins and fats in food bind to the tannins, which softens the wine's astringency and cleanses the palate, creating a more balanced and harmonious taste experience.

High levels of tannins are found in black tea, dark chocolate, unripe fruit, nuts like walnuts, and certain legumes.

Bitterness is a flavor perceived on the palate, while astringency is a textural or tactile sensation of dryness and roughness in the mouth.

No. While most red wines have some level of tannins, the concentration varies widely based on the grape variety and winemaking process. Varieties like Cabernet Sauvignon are higher in tannins than thinner-skinned grapes like Pinot Noir.

Winemakers can increase tannins by extending the maceration period (time juice spends with grape skins), using thick-skinned grape varieties, and aging the wine in new oak barrels.