Anchovies vs. Boquerones: Real Differences That Matter

This is probably the most misunderstood question at the fish counter: "Are anchovies and boquerones the same thing?" The answer is yes and no. They are the same fish, but not the same product. The distinction between anchovies and boquerones is not in the species but in how they are prepared, and that difference completely changes the flavor, texture, color, culinary use, and price. At Bacalalo, we explain it dozens of times a month at Mercat del Ninot, so here's the full version.

Let's start with the basics: both anchovies and boquerones come from the same fish, Engraulis encrasicolus, a small oily fish between 10 and 20 centimeters long that inhabits the Mediterranean and North Atlantic. What turns them into different products is the preservation technique applied after fishing.

The same fish, two radically different preparations

The difference between anchovies and boquerones is 100% in their preparation:

Boquerones are Engraulis encrasicolus prepared in vinegar or fresh. Boquerones en vinagre are marinated in acetic acid (white wine vinegar), which denatures the proteins and "cooks" the fish without heat. The result is a white, firm product with a fresh, acidic flavor. In ceviche, the same process is called "cold cooking" with lemon.

Anchovies are the same fish cured in salt for months. The boquerón is cleaned, pressed into barrels alternating layers of salt and fish, and left to ferment for 8 to 18 months at a controlled temperature (between 18 and 25 degrees Celsius). During this time, the fish's own enzymes transform proteins into glutamate amino acids, which generates the powerful umami flavor of the anchovy. The color changes from silvery-gray to reddish-brown. The texture becomes softer and oilier.

This transformation process converts the boquerón, which fresh has between 120 and 150 kcal per 100g, into an anchovy with between 200 and 230 kcal per 100g, with a completely different nutritional and organoleptic profile.

Visual differences: how to identify each product

If you have both products in front of you, distinguishing them is immediate:

Color:

• Boquerón en vinagre: pearly white, almost opaque
• Anchovy in oil: reddish-brown, with shades ranging from cinnamon to dark brown depending on the curing

Texture:

• Boquerón: firmer, the flesh separates into thin flakes
• Anchovy: softer and more unctuous, tending to fall apart if handled too much

Flavor:

• Boquerón: acidic, fresh, with vinegar notes, almost no seafood flavor
• Anchovy: intense, salty, with a strong umami presence, long-lasting, marine aftertaste

Price:

• Boquerón en vinagre: 8-15 euros per kg, depending on size and quality
• Quality Cantabrian anchovy: 60-300 euros per kg of clean fillet (equivalent), depending on size and producer

Culinary uses: when to use each one

The confusion between anchovies and boquerones creates real problems in the kitchen when one is substituted for the other. They are not interchangeable:

Use boquerones when:

• You want a fresh, acidic appetizer
• The recipe calls for something white (it should not alter the color of the dish)
• You are looking for a mild flavor that won't overpower the dish
• The dish is not going to be cooked (salad, direct tapa)
• You are preparing fried boquerones, which are fresh boquerones breaded and fried, not boquerones in vinegar

Use anchovies when:

• You want umami flavor depth in a sauce or stew
• The recipe needs that salty and intense touch (puttanesca sauce, anchovy butter, pil-pil)
• You are preparing a Basque gilda (the correct ingredient is always salted anchovy, never boquerón in vinegar)
• You are working with pizza, pasta with anchovies, or tapenade
• You are using the "umami hack": an anchovy dissolved in sautéed oil will add depth to any meat or vegetable stew without tasting fishy

Bacalalo Products

Cantabrian Anchovies in Olive Oil - 50g

€3.95

"Cantabrian Deluxe" Assortment

€67.00

Artisanal Cantabrian Anchovy Gilda

€9.90

Northern White Tuna Belly - Olasagasti

€16.95

Refrigerated shipping 24-48h throughout the Peninsula

The curing process: why everything changes

To deeply understand the difference between anchovies and boquerones, one must understand the chemistry that occurs in each process:

In boquerones en vinagre, acetic acid (CH3COOH) at a concentration of 5-7% denatures the protein in the fish muscle. The protein chains unfold and rearrange, giving it that white, firm texture. The process is not fermentation: there is no bacterial transformation, only chemical denaturation by acidity. The boquerón loses its silvery color and becomes opaque white because the muscle myosin changes its optical structure.

In salted anchovies, the process is completely different. Salt dehydrates the fish in the first hours, creating a hypertonic environment that stops bacterial growth. Then, for weeks and months, the fish's own proteolytic enzymes (cathepsins, collagenases) break down proteins into free amino acids, including monosodium glutamate, which is the molecule responsible for the umami flavor. It is literally a process of controlled self-digestion, similar to the maturation of cheese or ham.

The oil in which the anchovy is preserved is not a minor ingredient: it protects against oxidation, carries aromatic compounds, and adds its own flavor. An anchovy in extra virgin olive oil tastes different from the same anchovy in sunflower oil.

Nutritional differences between anchovies and boquerones

The confusion between anchovies and boquerones also matters from a nutritional point of view, because their profiles are different:

Fresh boquerón (100 g):

• Calories: 130-150 kcal
• Proteins: 19-21 g
• Fat: 5-8 g
• Sodium: 80-120 mg
• Omega-3: 1-2 g

Anchovy in olive oil (100 g):

• Calories: 200-230 kcal
• Proteins: 23-27 g
• Fat: 12-16 g (partially from the preserving oil)
• Sodium: 3,000-4,500 mg (very high due to salting)
• Omega-3: 1.5-2.5 g

The difference in sodium is enormous and must be taken into account. Anchovies are a high-sodium food by definition. They are not suitable for very salt-restricted diets, although typical serving sizes (2-4 fillets, about 10-15g) reduce actual intake to manageable levels.

Confusion in restaurants and how to avoid it

In many restaurants and bars, especially mid-to-low-end ones, the terms are used inaccurately. Asking for "anchovies" and receiving boquerones en vinagre is a common occurrence. To avoid this:

• If you want salted anchovies, specify: "Cantabrian anchovies in oil, salt-cured"
• If you want boquerones en vinagre, say: "boquerones en vinagre" or "white boquerones"
• Authentic gilda uses salted anchovies, not boquerones en vinagre. If you are served gilda with white fillets, they are using boquerones

One detail worth mentioning: in southern Spain and some areas of Levante, the word "anchoa" is sometimes used to refer to small fresh boquerones. This regional ambiguity adds to the confusion surrounding anchovies and boquerones, but in the context of quality preserves and tapas, the terms are used as we have described.

Bacalalo Products

Cantabrian Anchovies AOVE - 50g

€3.95

Artisanal Cantabrian Anchovy Gilda

€9.90

"Cantabrian Deluxe" Assortment

€67.00

Northern White Tuna Belly - Olasagasti

€16.95

Refrigerated shipping 24-48h throughout the Peninsula

Frequently asked questions about anchovies and boquerones