How to Concasse a Tomato: Professional Technique Explained

Concasse a tomato means to peel, seed, and dice it into uniform pieces—a French culinary technique essential for sauces, soups, and dishes requiring smooth texture without excess moisture. Master this method to elevate your cooking with professional results.

Ever wondered why restaurant tomato sauces taste smoother and more refined than your homemade versions? The secret often lies in a simple French technique called concasse. This precise method transforms ordinary tomatoes into a chef's secret weapon for creating restaurant-quality dishes at home. Whether you're making a classic marinara, fresh salsa, or elegant bruschetta topping, understanding how to properly concasse a tomato unlocks better texture, flavor control, and visual appeal in your cooking.

What Exactly Is Concasse and Why It Matters

The term concasse (pronounced kawn-kahs) comes from the French verb concasser, meaning "to crush" or "to chop coarsely." In culinary practice, it specifically refers to the process of peeling, seeding, and dicing tomatoes. Unlike regular chopping, concasse removes the skin and seeds—the parts that can make sauces watery or create unpleasant texture.

Professional chefs rely on this technique because it delivers three critical advantages:

• Texture perfection – Eliminates tough skins and gelatinous seeds
• Flavor concentration – Removes excess water that dilutes taste
• Visual appeal – Creates uniform pieces that distribute evenly in dishes

Preparation Method	Skin Removed	Seeds Removed	Best For
Concasse	Yes	Yes	Sauces, soups, refined dishes
Chopped	No	No	Salsas, salads, rustic dishes
Diced	Optional	No	Cold dishes, garnishes
Puréed	Yes	Yes	Smooth sauces, soups

The Evolution of Concasse in Culinary Practice

While the term entered English culinary vocabulary in the mid-20th century, the technique itself has deeper roots. French chefs adopted concasse during the 19th century as part of Escoffier's movement toward refined, consistent preparations. Before this, tomatoes were often used whole or roughly chopped in European cooking.

Key developments in the technique's history:

• 1820s – Tomatoes gain acceptance in French cuisine after being considered poisonous
• 1884 – Escoffier's Le Guide Culinaire standardizes many French techniques including tomato preparation
• 1950s – American culinary schools begin teaching French methods including concasse
• Today – Concasse remains fundamental in professional kitchens worldwide

When Concasse Is Essential (and When It's Not)

Understanding the context boundaries for this technique prevents unnecessary work. Concasse shines in specific applications but becomes counterproductive in others.

Use concasse when:

• Creating smooth tomato sauces (marinara, arrabbiata)
• Preparing cold tomato soups (gazpacho)
• Making refined dishes where texture matters (bruschetta topping, egg dishes)
• Working with large quantities where consistency is crucial

Avoid concasse when:

• Preparing rustic salsas or salads
• Cooking dishes where tomato structure should remain intact (stuffed tomatoes)
• Using cherry or grape tomatoes (too small for practical seeding)
• Creating dishes that benefit from tomato seeds' gel (some traditional Italian sauces)

Step-by-Step: Perfect Concasse Technique

Follow these professional steps for flawless results every time. The entire process takes just 5-7 minutes with practice.

What You'll Need

• Ripe but firm tomatoes (Roma/plum varieties work best)
• Sharp paring knife
• Slotted spoon
• Bowl of ice water
• Small serrated knife (optional for scoring)

The Blanching Process

Blanching loosens the skin without cooking the tomato:

1. Score an "X" on the bottom of each tomato with a small knife
2. Boil water in a medium pot (enough to cover tomatoes)
3. Prepare ice water bath in a large bowl
4. Submerge tomatoes for 30-45 seconds (timing is critical)
5. Immediately transfer to ice bath for 1 minute
6. Peel skin starting from the "X" (should slide off easily)

Seeding and Dicing

Proper seeding removes excess moisture while preserving flavor:

1. Cut tomato in half horizontally through the equator
2. Gently squeeze each half over a bowl to remove seeds and excess juice
3. Use your finger or small spoon to scrape out remaining seeds
4. Place cut-side down and slice into even strips
5. Cross-cut strips into uniform 1/4-inch cubes
6. Pat dry with paper towel if using immediately

Common Mistakes and How to Avoid Them

Even experienced home cooks make these errors that compromise results:

• Over-blanching – Tomatoes become too soft (stick to 45 seconds max)
• Under-blanching – Skin doesn't peel easily (add 5-10 seconds if needed)
• Incorrect tomato selection – Use firm, ripe Romas (avoid overripe or mealy tomatoes)
• Improper seeding – Leaving too much gel causes watery sauces
• Inconsistent dicing – Creates uneven cooking (aim for uniform 1/4-inch pieces)

Professional Applications and Storage Tips

Concassed tomatoes work magic in these professional applications:

• Tomato sauces – Creates smooth base without straining
• Cold soups – Maintains fresh flavor without seed bitterness
• Egg dishes – Prevents watery frittatas and quiches
• Garnishes – Provides clean appearance for finished dishes

Storage guidelines:

• Refrigerate in airtight container for up to 3 days
• Freeze on baking sheet then transfer to freezer bag for up to 3 months
• Never store concassed tomatoes in their own liquid (drain excess moisture)
• For sauces, freeze in ice cube trays then transfer to bags

Mastering Tomato Preparation for Culinary Excellence

Concasse represents more than just a chopping technique—it embodies the chef's attention to detail that transforms ingredients into exceptional dishes. By removing elements that compromise texture and flavor concentration, this method honors the tomato's natural qualities while adapting it to refined culinary applications. The slight extra effort pays dividends in professional-quality results that elevate everyday cooking. Whether you're preparing a simple weeknight pasta or entertaining guests, mastering concasse gives you a fundamental skill that professional chefs rely on daily.

What does concasse mean for tomatoes?

Concasse refers to the culinary technique of peeling, seeding, and dicing tomatoes into uniform pieces. This French method removes the skin and seeds to create a refined texture ideal for sauces and dishes where smooth consistency matters.

Do I need special equipment to concasse tomatoes?

No special equipment is required. You only need a sharp knife, pot for boiling water, bowl of ice water, and slotted spoon. The technique relies on proper timing and handling rather than specialized tools.

Can I skip blanching when concassing tomatoes?

Blanching is essential for easy peeling without damaging the tomato flesh. Attempting to peel unblanched tomatoes often results in torn flesh and inconsistent results. The 30-45 second blanch followed by ice bath is the professional standard for perfect skin removal.

Which tomato varieties work best for concasse?

Roma (plum) tomatoes are ideal due to their lower moisture content, fewer seed cavities, and meatier texture. Avoid overly ripe tomatoes as they become too soft during blanching. Cherry tomatoes aren't suitable as they're too small to seed effectively.

How long do concassed tomatoes last in the refrigerator?

Properly stored concassed tomatoes last 2-3 days in an airtight container in the refrigerator. For best results, drain excess liquid and store in a single layer with paper towels to absorb moisture. Never store them submerged in their own juices.