Potential of microalgae as flavoring agents for plant-based seafood alternatives

Use of algae as food ingredient: sensory acceptance and commercial products

“…One of the main important aspects of using algae in food systems are related to the palatability of algal biomass in terms of sensory input induced by aroma, color, taste (salty, sweet, sour, bitter, and umami) and textural mouthfeel (Isleten Hosoglu, 2018). The main characteristics of aroma in algae biomass is derived from a complex mixture of different odor-active volatile chemical compounds as stated by Coleman et al (2022). In particular, four classes of typical odor-active volatile chemicals in algae are known: 1) fatty acid-derived volatiles compounds (aldehydes, alcohols and ketones) originated from the lypoxygenase activity or autoxidation of polyunsaturated fatty acids; 2) sulfuric compounds such as dimethyl sulfuric (DMS, C 2 H 6 O 4 S), dimethyl disulfide (DMDS, C 2 H 6 S 2 ) and methanethiol (CH 4 S); 3) nitrogen-containing compounds such as trimethylamine (TMA, C 3 H 9 N) originated from the action of microbial activity that reduces osmolyte trimethylamine oxide (TMAO) into TMA; and 4) umami taste compounds related to the presence of specific free amino acids such as glutamate (Glu) and aspartate (Asp) as well as nucleotides, notably inosine monophosphate (IMP), guanosine monophosphate (GMP) and adenosine monophosphate (AMP).…”

“…In contrast to seaweeds, there is little knowledge about the contribution of flavor in microalgae biomass, despite the ample attention received by these microorganisms in the past decade as a novel source of food. For this reason, the aroma and taste of eight different phototrophic microalage species were investigated and compared with five seaweeds to evaluate their potential as flavor ingredients in plantbased seafood alternatives (Coleman et al, 2022). According to the results, microalgae Rhodomonas salina, Tetraselmis chui, and Phaeodactylum tricornutum have a stronger seafood odor and taste features compared to seaweeds.…”

“…It is important to highlight that high protein content (28%-71% dry weight) of certain microalgae (Becker, 2007) could result in a high amount of free amino acids notably glutamic acid and aspartate, causing high umami taste desirable for the imparting flavor in plant-based seafood alternative (Coleman et al, 2022), whereas fishy off-flavors of microalgal biomass may be unwanted for certain food products (dairy foods, cookies, pasta, beverages, among others). In this way, advanced studies and investigations on the phytochemical compounds in microalgae are important to reveal the presence of volatile organic compounds that directly affect the sensorial properties of algal-based food products as well as its acceptance (Francezon et al, 2021).…”

“…Disguising ingredients may increases familiarity with algae biomass due to its potential ability to mimic certain food ingredients such as seafood (Francezon et al, 2021). For example, the microalgae R. salina has the potential ability to act as flavoring agent in plant-based seafood because of its crab aroma, while Tetraselmis chui and Phaeodactylum tricornutum have strong seafood odor and a taste characterized by high umami and crab/shellfish flavor, which can be used to disguise flavor of animalbased seafood products (Coleman et al, 2022).…”

“…Microalgae are also increasingly used as ingredient for foods as a flavor active, texture enhancer or nutrients source (Coleman et al, 2022). Among the best-known microalgae species are Arthrospira platensis (Spirulina) and Chlorella vulgaris, which can act as a vegan protein source due to their high protein content (50%-60% of dry weight) with a complementary roll of essential amino acids and vitamin B 12 (Figure 1) (Matos, 2019).…”