How to Ferment Surströmming

Mastering Swedish Fermented Herring at Home

Surströmming, a traditional Swedish delicacy, is a type of fermented herring from the Baltic Sea that has been an integral part of Swedish cuisine since at least the 16th century. The distinctive taste and aroma of surströmming have been both celebrated and notoriously challenged by many, making it an iconic yet divisive element of Northern European food culture. This unique dish begins with the strömming, a type of Baltic herring smaller than the Atlantic herring, which is the only fish acceptable for authentic surströmming.

The fermentation process of surströmming is a precise and time-honored technique. After the strömming are caught in the spring, they are salted to prevent rotting. The salt initiates fermentation, a critical stage where the fish develop their characteristic sour flavor. After being sealed in cans, the herring continues to ferment, which produces the slight bulging due to gas buildup recognizable in cans of authentic surströmming.

Sweden's affinity for fermented fish is deeply rooted in its culinary traditions, and surströmming stands out as a symbol of this heritage. While the potent smell may be startling at first, the taste of surströmming when properly prepared and paired with traditional sides such as boiled potatoes, sour cream, and flatbreads, offers a complete Swedish gastronomic experience. It's a bold flavor that connects people to a part of Swedish history and continues to intrigue and challenge palates across the world.

History and Tradition

Surströmming has a storied past, deeply rooted in Swedish culture, with recorded consumption dating back to at least the 16th century. This section explores its origins and how it has come to hold a significant place in Swedish traditions.

Origins of Surströmming

Surströmming's inception is linked to Swedish innovation and preservation techniques. The early methods employed by the Swedes for preserving herring were influenced by the salting practices used by the Greeks and Romans. However, due to a salt shortage in Sweden, the locals in the coastal areas of Hälsingland began fermenting herring with just enough salt to prevent it from rotting, thereby creating surströmming. This technique allowed the fish to ferment naturally, leading to the distinct character that surströmming is known for today.

Cultural Significance in Sweden

In Sweden, surströmming is more than just a food item; it's a cornerstone of cultural identity for traditionalist Swedes. Gathering to enjoy surströmming, typically in events known as surströmmingsskiva, has become an integral part of the social fabric. These events often occur around the time of the surströmmingspremiären, the anticipated release of that year's batch of surströmming, which by custom takes place on the third Thursday of August. Feasting at a surströmmingsskiva is a festive nod to Sweden's history and an enactment of community spirit where the pungent aroma of surströmming fills the air as Swedes revel in this long-standing tradition.

The Science of Fermentation

In the production of Surströmming, the fermentation process is essential. It transforms Baltic Sea herring into the distinctive Swedish delicacy. Central to this transformation are specific enzymes and conditions, including the lactic acid bacteria, salinity levels, and temperature control, which together craft the unique flavor and texture of the final product.

Role of Lactic Acid in Fermentation

Fermentation is driven by lactic acid bacteria, which metabolize sugars in the absence of oxygen to produce lactic acid. This acidification preserves the herring by lowering the pH, effectively preventing the growth of spoilage organisms and pathogens. The enzymes from these bacteria are pivotal; they not only safeguard the fish but also contribute to its characteristic tangy taste.

• Lactic acid bacteria: Converts sugars into lactic acid.

• pH reduction: Creates an inhospitable environment for harmful bacteria.

• Flavor development: A tangy taste unique to Surströmming.

Salt Concentration and Its Effects

Salt plays a multifaceted role in the fermentation of Surströmming. It must be carefully managed to avoid an environment that is either too hospitable for unwanted microbes or too inhibitory for the necessary fermentation process. A moderate salt concentration ensures the lactic acid bacteria can thrive while inhibiting unwanted microorganisms.

• Optimal concentration: A delicate balance that permits the growth of desirable lactic acid bacteria while inhibiting spoilage agents.

• Salt shortage: Inadequate salt can lead to spoilage and off-flavors.

• Temperature control: Temperature works in concert with salt concentration, influencing the rate of fermentation and enzyme activity.

By maintaining these specific conditions, Surströmming producers are able to consistently create a product that is not only edible but celebrated for its unique qualities.

Preparing Surströmming

Surströmming, a traditional Swedish delicacy, requires meticulous preparation to achieve its distinctive taste. The process involves careful selection of ingredients and proper canning techniques to avoid any potential hazards.

Selecting the Right Ingredients

One must select the proper type of herring to make authentic surströmming. The Baltic herring, or strömming, is smaller than the Atlantic herring and is the only fish suitable for this dish. The timing of the catch is also crucial; the Baltic herring should be fished in the spring when they are in prime condition for fermentation.

Another key ingredient is salt. It's essential for the fermentation process, inhibiting the growth of unwanted bacteria and promoting the development of desired fermentation agents.

Canning and Storage Methods

Canning is a critical step in creating surströmming. Once the herring has been cleaned and gutted—heads and innards removed—the fish are layered with salt in barrels. These barrels are then tightly sealed and left to ferment, allowing gases to build up. This step requires precision, as improper canning can lead to too much pressure build-up, potentially causing the cans to expand or, in rare cases, explode.

After initial fermentation in the barrels, the herring is transferred to cans. Fermentation continues inside the cans, which are equipped to handle the pressure of the gases. Nevertheless, handlers must store the cans in a cool place and routinely monitor them to prevent any risk of exploding, ensuring the final product is safe for consumption.

Serving Suggestions

When enjoying Surströmming, the serving method significantly enhances the experience. The strong flavor and aroma of this Swedish delicacy are traditionally balanced with specific accompaniments.

Traditional Accompaniments

Tunnbröd, a soft flatbread, typically serves as the base for creating a dish known as surströmmingsklämma. This includes layers of mandelpotatis, a variety of almond-shaped potatoes recognized for their nutty flavor, and finely chopped onions or red onions to add a fresh and sharp contrast to the rich fish. Crispbread is another common base alternative to tunnbröd, delivering a pleasant crunch. Swedes often complement the meal with a selection of beverages, including beer, specifically lager, and snaps—a spiced and flavored spirit. Akvavit or vodka can also accompany the meal, balancing the strong tastes with their potent clean flavors.

• Base: Tunnbröd or crispbread

• Toppings: Mandelpotatis, onions or red onions

• Beverages: Lager, snaps, akvavit, or vodka

Modern Serving Ideas

Modern interpretations of Surströmming servings play with a variety of textures and flavors to suit contemporary palates. Some enthusiasts recommend a less traditional approach, like dicing the Surströmming and incorporating it into a salad served with a robust dressing to counteract its potency. Progressive Swedish chefs might pair the fermented herring with puréed potatoes for a smoother mouthfeel or present it atop canapés for a bite-sized treat at gastronomic events. The key to modern serving ideas is to respect the powerful essence of Surströmming while introducing elements that invite curiosity and palatability.

• Salad inclusion: Diced Surströmming with a balancing dressing

• Puréed partner: Smooth potato purée

• Canapé options: Small, elegant bites with Surströmming as the centerpiece

Safety and Storage Guidelines

When dealing with surströmming, safety and storage are paramount to prevent injury and spoilage. The can contains fermented herring, and incorrect handling or storage can lead to issues like bursting from built-up pressure.

Handling The Can Safely

One must exercise caution when handling surströmming cans. As the fermentation process continues inside the sealed container, gases can accumulate, increasing internal pressure which may lead to exploding cans if not treated carefully. Individuals should:

• Open cans outdoors: Due to potential pressure and the strong odor, always opt to open surströmming cans outside.

• Use proper tools: Employ a can opener and wear safety gear, such as gloves and eye protection.

Storing Surströmming Properly

Proper storage of surströmming is essential to maintain its quality and avoid accidents. It is advised to keep the cans in a cool environment such as a fridge to reduce gas buildup and control fermentation. Here's how to store surströmming:

• Refrigeration: Always store unopened cans in the refrigerator. This limits fermentation activity and pressure build-up, making it safer to handle the cans.

  • Temperature: Below 8°C (46°F)

    • Storage Location: Fridge

• After Opening: Once opened, surströmming should be consumed quickly. Any leftovers should be transferred to a sealed container and kept in the fridge for no more than a few days.

Surströmming Events and Experiences

Surströmming events offer a unique way for people to come together and share their appreciation for this distinctive part of Swedish culinary tradition. These events range from the first taste of the season to challenging festivals celebrating this audacious delicacy.

The Surströmmingspremiär

The Surströmmingspremiär, or 'surströmming premiere', marks the start of the surströmming season which typically occurs on the third Thursday of August. This event is a cultural highlight in Sweden and involves the first opening of the surströmming cans of the season, often accompanied by social gatherings and traditional festivities. Surströmming aficionados celebrate with friends and family, enjoying the fermented herring with accompaniments like flatbreads, potatoes, and a cold beverage, usually milk or beer.

• Date: Third Thursday of August

• Key Components:

  • Opening of the cans

  • Social gatherings

  • Traditional food accompaniments

Surströmming Challenge and Festivals

Surströmming challenges have become increasingly popular, especially with the rise of social media where participants attempt to withstand the strong odor and taste of surströmming. These challenges often occur at festivals or as standalone events, drawing both locals and tourists eager to test their limits. These events are not only about the challenge but also serve as a celebration of this historic Swedish dish and an opportunity for cultural exchange.

• Activities:

  • Surströmming Challenge: Participants open and eat surströmming, often filmed for social media.

  • Festivals: Combine music, food stalls, and surströmming tasting sessions.

During these festivals, vendors may provide surströmming samples alongside other Swedish dishes, allowing everyone to explore Sweden's gastronomy more broadly. The festivals are family-friendly, promoting a convivial atmosphere that welcomes all to partake in the spirit of the event, whether one dares to taste the surströmming or not.

Consumer Insights

When seeking to purchase and consume Surströmming, one must consider the availability of suppliers and the management of the fish's potent odor. These factors are crucial for a satisfactory experience with this traditional Swedish delicacy.

Finding Surströmming Suppliers

Swedish Surströmming Suppliers are typically specialized and may not be widely available outside of Sweden. Consumers within Sweden can often find Surströmming in local supermarkets, especially in northern regions. For those outside Sweden, it is advisable to look for Swedish or Nordic specialty stores or online vendors that can provide international shipping. It's important to check for authentic sources to ensure the product's quality and to support traditional methods of production.

• Key Suppliers:

  • Local supermarkets in Sweden

  • Specialty Nordic shops

  • Licensed online retailers

Dealing with the Strong Odor

The strong smell of Surströmming is notorious and can be overwhelming. Odor management is essential when planning to consume the fermented fish. Consumers are advised to open the can of Surströmming outdoors and to handle the product in well-ventilated areas. Some individuals prefer to open the cans submerged in a bucket of water to reduce the release of the smell. Surströmming should be stored in cool conditions and disposed of properly to avoid lingering odors.

• Odor Management Tips:

  • Open the can outside or in a ventilated space

  • Consider opening the can underwater

  • Store it in a cool area

  • Dispose of it responsibly

Culinary Controversies

Surströmming, a fermented Baltic herring, elicits strong reactions, making it a subject of debate and regulation. Its odor and taste provoke a spectrum of opinions, making it a consistent source of culinary contention.

Ban and Regulation Discussions

Rules surrounding surströmming are often centered around its potent aroma, which is strong enough to be considered a public disturbance in some situations. This has led to discussions about bans on airlines and in public spaces. In fact, several airlines have banned surströmming due to its potential to disrupt fellow passengers with its smell.

Global Perception of Surströmming

Worldwide reactions to surströmming vary, but it often finds a place in discussions of the most challenging foods to try. For instance, the Disgusting Food Museum in Malmö, Sweden, includes surströmming as an exhibit, showcasing it as a noteworthy example of divisive tastes. Despite its controversial status, it has also sparked curiosity, with food enthusiasts and cultural explorers eager to experience its unique flavor profile, further altering its perception on the global stage. Surströmming’s reputation has even reached New York City, where it has been both criticized and celebrated by those brave enough to sample it at cultural events.

Pairing and Culinary Combinations

Surströmming, a traditional Swedish delicacy, is renowned for its strong aroma and robust flavor, often leading to careful consideration when pairing with beverages and other cuisines. The right pairings can enhance the dining experience, balancing the intense character of surströmming.

Select Alcoholic Pairings

Aquavit and beer are traditional Swedish beverages commonly paired with surströmming. Aquavit, with its distinctive flavor of spices and herbs, complements the fish's fermented taste. Light-bodied and crisp beers can also counterbalance the pungency of the herring, providing a refreshing contrast.

• Aquavit Pairing: Served chilled, it contrasts surströmming's potent flavor.

• Beer Pairing: A light lager cools the palate after the herring's impact.

Integration with Other Cuisines

Incorporating surströmming into various dishes requires subtlety due to its prominent taste. Worcestershire sauce, with its tangy flavor profile, may be used sparingly to create a marinade that can soften the surströmming's sharpness. Surströmming should not overshadow the flavors of Swedish meatballs; rather, it can be presented alongside as part of a broader Swedish culinary experience.

• Marinade Suggestion: A dash of Worcestershire sauce for a nuanced flavor with surströmming.

• Swedish Meatballs: Serve separately to appreciate both traditional flavors.

The Future of Surströmming

The future of Surströmming hinges on balancing time-honored techniques with contemporary market expansion. This delicate equilibrium strives to sustain Surströmming's cultural heritage while exploring its potential beyond Swedish borders.

Conservation of Traditional Methods

The High Coast region, recognized for its pristine conditions ideal for Surströmming production, remains a bastion of tradition. Here, producers adhere to age-old methods: small Baltic herrings are caught in spring, salted, and left to ferment. Sourcing from Alfta and similar towns ensures the continuation of this culinary legacy. Authorities and artisans work together to protect these practices, possibly through geographical indication statuses akin to those in wine production.

Innovation and New Markets

As Surströmming producers look to innovate, they consider the palate preferences of an international audience. Grocers and specialty stores may soon offer modified recipes or pairing suggestions that appeal to new consumers. While the product's presence in foreign grocery stores is nascent, online platforms emerge as a driving force for introducing Surströmming to new markets. Marketing focuses on educating consumers about the dish's unique attributes and the proper way to enjoy it, ensuring that its introduction to new palates is sophisticated and genuine.

Health Aspects and Nutritional Value

Surströmming brings a unique set of health benefits and nutritional advantages due to its fermentation process and contents. This section delves into the probiotic benefits of fermented foods like surströmming and considerations for those with specific dietary restrictions.

Probiotic Benefits of Fermented Foods

Fermented foods, including Surströmming, are known for their probiotic properties, which support gut health. The fermentation process encourages the growth of beneficial bacteria, such as lactic acid bacteria, which are crucial for maintaining a healthy digestive system. By promoting a balanced intestinal flora, these probiotics can enhance the immune system and improve digestion.

Considerations for Dietary Restrictions

When it comes to dietary restrictions, consumers should be aware of Surströmming's particularly high salt content, a result of the fermentation process intended to prevent rotting. Individuals on sodium-restricted diets or those with certain health conditions should consume it cautiously. Additionally, unlike milk-based probiotic foods, surströmming does not contain lactose, making it an option for those with lactose intolerance.

For those looking to include surströmming in a meal, it is often enjoyed in a sandwich form known as surströmmingsklämma, comprising a piece of buttered flatbread, boiled potatoes, onions, and surströmming. While this combination harmonizes flavors, the added components should be considered for their additional nutritional values and potential dietary restrictions.

Culinary Adaptations and Variations

Surströmming, the potent Swedish delicacy, can be adapted into a variety of dishes that often mellow its strong flavor while celebrating its unique character. Chefs have creatively augmented traditional recipes, ensuring this fermented herring can appeal to a wider audience and cater to different dietary restrictions.

Surströmming in Fusion Dishes

Innovative chefs incorporate Surströmming into fusion cuisines, often pairing it with components that complement the herring's robust taste.

• Sushi Rolls: Surströmming replaces traditional seafood, softened with avocado and cucumber to balance its intensity.

• Pasta: Finely chopped Surströmming is added to creamy pasta sauces, often with gräddfil or crème fraîche for a Scandinavian twist.

Key Ingredients:

• Chives: Adds a mild onion flavor without overpowering the herring.

• Dill: Offers a sweet and citrusy note that pairs well with seafood.

• Gräddfil/Crème Fraîche: Provides a creamy texture and slight tanginess to sauces.

Alternate Preparations for Dietary Needs

Surströmming can be prepared to accommodate various dietary preferences and restrictions without compromising the essence of the dish.

• Gluten-Free: Surströmming is served on a bed of lettuce instead of bread, garnished with dill and chives for flavor.

• Dairy-Free: Replace gräddfil or crème fraîche with dairy-free alternatives to make the accompanying sauces suitable for lactose intolerance.

Adaptations:

• For those avoiding gluten, using gluten-free crispbreads or potato slices as a base maintains traditional elements.

• Incorporating västerbottensost, a Swedish cheese, can add depth to the flavor profile for those without dairy allergies.

Through these adaptations, Surströmming becomes accessible to a diverse set of palates while remaining a celebrated part of Swedish culinary heritage.

Conclusion

Surströmming, a notable item in Swedish culinary tradition, is a testament to age-old food preservation methods. Through fermentation, Baltic herring is transformed into a distinctive delicacy, celebrated especially during the surströmming season from August. Food lovers and the culturally curious often gather for a surströmming party to partake in this unique experience.

It's crucial to acknowledge that enjoyment of surströmming may vary among individuals. Preparing and serving the fish requires specific steps, such as opening the can outdoors and pairing it with the appropriate accompaniments. Safety is paramount, as the can is pressurized and fermentation continues until opened.

Those interested in preparing surströmming should respect the time-honored process, understanding that taste develops over several months. Due to its potent aroma and distinctive flavor, newcomers should approach with an open mind. They can expect a culinary adventure that's deeply rooted in Swedish heritage.

In summary, surströmming stands as a cultural hallmark, calling on adventurers and food enthusiasts to explore its bold character. As with all fermented foods, it exemplifies human ingenuity in the realm of food preservation, offering a unique way to connect with Swedish customs and communal gatherings.