Ketchup might soon offer more than just its classic sweet and tangy taste. Researchers have crafted a protein-enhanced version of this popular condiment using extracts from microalgae, presenting a potentially more sustainable way to boost nutrition in everyday foods.
Published in ACS Food Science & Technology, the study explored whether protein derived from the microalga Chlorella vulgaris could be incorporated into tomato ketchup without altering its flavor, color, or overall attractiveness.
As protein-enriched foods become increasingly common—appearing in items like breakfast cereals, pasta, and snacks—most brands tend to rely on familiar sources such as whey, soy, or peas. The researchers aimed to explore algae as an alternative protein source. According to lead researcher Parise Adadi, the goal was to enhance the nutritional profile of a widely consumed condiment using a sustainable protein source.
Microalgae like Chlorella vulgaris offer several environmental benefits. It grows rapidly throughout the year and can be cultivated using relatively little land and freshwater compared to traditional crops. Naturally rich in protein, it presents an eco-friendly option for food production.
However, there’s an obvious challenge: taste. Algae often have a distinctive flavor that can be overpowering in certain applications. While this flavor can complement some foods—such as plant-based seafood, where a slight fishiness can be beneficial—it could negatively impact ketchup’s familiar taste.
To address this, the researchers extracted protein from C. vulgaris and experimented with various ketchup formulations containing between 1% and 13% of algal protein. These versions still included traditional ingredients like plum tomatoes, sugar, vinegar, salt, spices, and citric acid. A control batch of regular ketchup without algae was also prepared for comparison.
After bottling and pasteurizing the products, a panel of 15 taste testers evaluated their flavor and appearance. The results showed that lower concentrations of algae—specifically 1% and 3%—kept the taste close to the original, with only a slight algal flavor detectable and the usual sweet, tangy, and mildly spicy profile intact. These versions maintained consumer appeal.
Higher concentrations, however, posed problems. At 5% and 13%, the ketchup developed a stronger algal taste and a greenish hue, which decreased its overall attractiveness for most testers.
Despite these sensory challenges, the nutritional gains were substantial. Ketchup with 3% and 5% algal extract contained about two to three times more protein than plain ketchup. They also provided more essential amino acids, minerals like iron and sodium, and antioxidants—making them a healthier option.
The study suggests that incorporating a moderate amount of algal protein can enhance ketchup’s nutritional value without sacrificing its familiar qualities. However, further research is needed before algae-enriched ketchup hits store shelves. Future plans include larger consumer testing, examining how well the product maintains quality during storage, and determining whether it can be produced on a commercial scale successfully.
