|Free Amino Acids & 5’-Nucleotide content of Seaweeds : A Chemical Assessment of Taste|
Fremouw, R. (2018). Free Amino Acids & 5’-Nucleotide content of Seaweeds : A Chemical Assessment of Taste. Thesis. NIOZ Royal Institute for Sea Research: Yerseke. 61 pp.
In this study, various extraction methods were compared based on their ability to extract both free amino acids, and free 5’-monophosphate nucleotides from the seaweed Saccharina latissima.Based on the results, extraction at room temperature with Milli-Q over 24 hours was chosen as the method of choice, as with it the highest concentration of nucleotides was obtained, and it most closely resembles the conditions of saliva, which consists of 99% water.Milli-Q extracts of various species of seaweed were afterwards obtained using the Milli-Q extraction protocol and analysed on their free amino acids (FAAs) and 5’-monophosphate nucleotide composition.Of the investigated species, L-Glutamic acid was the most abundantly available in the investigated samples of Gracilaria, suggesting umami taste. The sweet-tasting amino acid L-Alanine was the main free amino acid found in the two investigated Saccharina, with investigated Ulva sp. containing mainly L-Asparagine, indicating sour taste. 5’-monophosphate nucleotide composition was found to have both inter- and intra-species differences, despite this, umami enhancing 5’-nucleotides were found present in all of the analysed samples.Predictions on the taste of the analysed species of seaweed were made based on their chemical composition, looking at the FAAs and 5’-monophosphate nucleotides. However, taste is complex, and it is therefore recommended to combine extensive quantitative data with physical evaluation of the seaweeds, that has been carried out by expert taste panels, so that palatability can be accurately quantified.