Portuguese researchers have demonstrated how natural flavour compounds can significantly reduce salt levels in popular table sauces while preserving much of their familiar taste and texture.

Originally published research: 19 September 2024

Ketchup, mayonnaise and mustard are among the most familiar products in the global food industry. They accompany everything from hamburgers and French fries to sandwiches, salads and prepared meals. Yet these everyday condiments present a technological challenge for food manufacturers: how can they reduce salt without changing the qualities that consumers expect?

Researchers in Portugal believe they have found a promising answer.

In a study published in Frontiers in Nutrition on 19 September 2024, scientists demonstrated that specially formulated ingredients derived from aromatic plants and spices could reduce salt content by up to 52% in ketchup, 50% in mayonnaise and 45% in mustard.

The findings suggest that substantial reductions in sodium may be technologically feasible without fundamentally compromising the sensory characteristics of these products.

The challenge of removing salt

Salt is much more than a seasoning in processed foods. It contributes to flavour, influences product characteristics and can play a role in preservation.

Reducing its concentration is therefore not always as straightforward as removing an ingredient from a recipe.

Consumers have developed strong expectations about how familiar sauces should taste, look and feel. A mayonnaise that loses its characteristic texture or a ketchup that tastes noticeably different may struggle to gain acceptance, regardless of its nutritional advantages.

The researchers sought to address this challenge through a combination of food chemistry and ingredient technology.

Their work involved Portuguese research institutions, including the National Institute for Agricultural and Veterinary Research and the University of Lisbon, alongside other scientific partners and the food manufacturer Mendes Gonçalves.

The science of microencapsulation

The central innovation involved microencapsulated oleoresins.

Oleoresins are concentrated extracts from plants and spices containing compounds responsible for flavour and aroma.

Although these extracts can enhance the sensory characteristics of food, they also present technical difficulties. Some are sensitive to oxidation, have limited solubility in water or may affect the appearance of the finished product.

Microencapsulation offers a potential solution.

The technology surrounds selected ingredients with a protective carrier material, helping them remain stable and making them easier to incorporate into food formulations.

In this study, the researchers investigated several formulations using microencapsulated oleoresins, with inulin serving as a carrier.

The objective was to determine whether these ingredients could compensate for some of the flavour changes associated with reducing salt.

Testing three familiar sauces

The research team developed experimental versions of mayonnaise, mustard and ketchup.

These formulations were compared with conventional control products.

The scientists examined several characteristics, including mineral composition, acidity, oxidation, viscosity, colour and sensory properties.

The results were encouraging.

The reformulated products achieved salt reductions of up to 50% in mayonnaise, 45% in mustard and 52% in ketchup.

Importantly, the experimental formulations generally maintained sensory profiles similar to those of the control products.

Mayonnaise showed particularly close resemblance to its conventional counterpart.

Mustard displayed some differences in flavour and perceived saltiness, while ketchup retained a broadly comparable sensory profile despite certain changes in colour and consistency.

These findings indicate that salt reduction does not necessarily require a dramatic alteration of the eating experience.

However, the results do not establish that every reduced-salt sauce will perform equally well, or that the tested formulations will automatically succeed in commercial production.

Why texture and colour matter

The researchers also investigated physical and chemical properties that are essential to the quality of commercial sauces.

In many formulations, changes in acidity, lipid oxidation and viscosity were relatively limited.

The use of inulin helped preserve important textural properties.

Nevertheless, not every characteristic remained unchanged.

Certain ketchup formulations exhibited noticeable colour differences, while some products showed changes in consistency.

Such findings are important because the commercial success of a food product depends on more than flavour alone.

Consumers evaluate food through appearance, smell, texture and taste. A sauce that is chemically successful but visually unfamiliar may still face difficulties in the marketplace.

The research therefore illustrates both the opportunities and the limitations of ingredient reformulation.

A potential development for the food industry

The study has implications beyond the three sauces examined.

Food manufacturers face increasing pressure to improve the nutritional composition of processed foods while maintaining consumer acceptance.

Salt reduction is particularly relevant because excessive sodium consumption is associated with elevated blood pressure and increased cardiovascular risk.

Technologies that allow manufacturers to reduce sodium without substantially altering established products could contribute to broader public-health objectives.

The Portuguese findings provide a practical example of how food chemistry can support this process.

They also demonstrate the importance of collaboration between scientific institutions and manufacturers.

The research included employees of Mendes Gonçalves, a Portuguese food company, among its authors. This industry involvement is relevant to understanding the commercial context of the work.

What the research does not yet prove

The study demonstrates that substantial salt reductions can be achieved in the tested formulations.

It does not establish that consumers would purchase these products at the same rate as conventional sauces, nor does it demonstrate long-term health benefits from consuming the reformulated products.

Further research would be needed to evaluate commercial-scale performance, extended storage conditions, manufacturing economics and acceptance among larger and more diverse consumer populations.

Nevertheless, the findings point towards an important development in food science.

Instead of simply removing salt and accepting a loss of flavour, manufacturers may be able to redesign the way flavour is delivered.

For an industry built around familiar tastes, that could become an important technological advantage.

Scientific source

Original study: Serrano, C., Sapata, M., Castelo-Branco, D., Tasso, A., Marques, A., Viegas, C., Figueira, D. & Komora, N. (2024).

Title: The influence of salt reduction with encapsulated oleoresins on the quality of mayonnaise, mustard, and ketchup.

Journal: Frontiers in Nutrition, Volume 11, Article 1456319.

Original publication date: 19 September 2024.

DOI: https://doi.org/10.3389/fnut.2024.1456319

Research institutions: INIAV, University of Lisbon and collaborating Portuguese institutions and industry researchers.

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Image: Scientists are exploring new ways to reduce salt in everyday condiments without compromising their familiar sensory characteristics.