University of Copenhagen uses fermentation to tackle faba beans’ unwanted flavors

Researchers at the University of Copenhagen have used bacterial fermentation to reduce unwanted flavors in faba bean protein extracts, offering food manufacturers a way to improve an ingredient that is rich in protein but can struggle to appeal to consumers.

• University of Copenhagen researchers used selected bacteria to reduce green, beany off-flavors in faba bean protein extracts.
• Fermentation also developed nutty and umami-like flavors, with different bacteria producing different flavor profiles.
• The team sees potential to apply dairy fermentation expertise to a broader range of foods made from beans and peas.

The study examined how selected bacteria changed the extracts’ flavor chemistry. The researchers identified microorganisms that reduced the characteristic 'beany' notes while producing new flavor compounds, including those associated with nutty and umami-like flavors.

Faba beans can be grown readily in Denmark, yet they are more commonly used for animal feed than for human food. According to the researchers, one reason is that their flavor does not meet consumers’ expectations when compared with familiar animal proteins such as beef, pork and chicken.

For manufacturers developing foods with plant proteins, that creates a practical problem. An ingredient’s protein content and local availability can make it attractive to work with, but neither guarantees that people will enjoy eating the finished product.

“Consumers want food that resembles what they already know. A plant-based alternative to meat should not taste like beans. With natural fermentation, we have managed to reduce off-flavors in faba beans that give them a distinctive 'green' taste, while at the same time improving the overall flavor,” said senior author Lene Jespersen, a professor in the Department of Food Science.

The team fermented protein extracts from faba beans using selected bacteria and then analyzed changes in the chemical profile of flavor compounds. Comparing those changes allowed the researchers to identify which bacteria were most effective at removing unwanted notes and which generated new aromas.

That distinction matters for product development. Reducing an ingredient’s characteristic flavor addresses one problem, while developing flavors that suit the intended food gives manufacturers another reason to consider fermentation.

The findings concern fermented protein extracts, rather than a finished meat alternative or a consumer-tested food product. They identify changes in flavor chemistry that could inform subsequent development, while consumer acceptance of foods made with those ingredients remains a separate question.

“We can see that the plant protein from faba beans can develop nutty and umami-like flavors during fermentation. These are flavors that consumers generally appreciate, and this may make beans more attractive as a food ingredient,” said Jespersen.

The researchers also see fermentation as a potential alternative to using additives to improve plant-based foods. The process is already familiar from bread, yogurt and beer, where microorganisms help determine the characteristics of the finished product.

Applying that approach to faba bean protein could give manufacturers another tool when formulating foods for consumers seeking shorter ingredient lists. Whether it can replace a particular additive would depend on the product and the function that additive performs.

“We want to support industry efforts toward what is known as clean labeling—meaning products without additives or E-numbers. This is something many consumers are increasingly looking for,” said Jespersen.

Fermentation can also extend shelf life and, in some cases, contribute beneficial microorganisms. Those are broader possibilities associated with the process, however, rather than outcomes established for a commercial faba bean food in the account of this study.

The work draws on an approach that has long been central to Denmark’s dairy industry. In cheese and other dairy products, manufacturers use microorganisms to develop different flavors and textures. Selecting cultures is part of determining what a product will taste like and how it will behave.

Jespersen and her colleagues are interested in applying similar principles to plant proteins. Instead of treating beans and peas as ingredients whose existing flavors must simply be accommodated, they are investigating how specific microorganisms can help develop different flavor profiles.

The potential applications therefore extend beyond making faba bean protein suitable for foods designed to resemble meat. Fermentation could also support a wider selection of plant-based products with distinct tastes of their own.

For that approach, the choice of bacteria becomes a product development decision: different microorganisms may be useful for different flavor objectives. The study’s comparison of bacterial effects provides a basis for investigating those choices, although it does not establish a single culture or process suitable for every application.

The ambition is to develop more variety in how beans and peas are used as high-protein foods, taking inspiration from the diversity already achieved in dairy fermentation.

“Imagine being able to serve a plant-based platter in the same way we serve a cheese platter today—with a variety of products that taste good, offer diversity and have a high protein content,” said Jespersen.

If you liked this, check these out...‍

• DTU fermentation method triples lysine levels in faba beans

• Ohio State Researchers cut plant-protein odors by up to 99% with two-step fermentation breakthrough

• NTU mushroom fermentation gives soy by-product a protein and flavor boost