Evaluating the palatability of Tasmania’s native sea grapes (Caulerpa spp.): a potential new seafood

Abstract

We assessed the palatability of four Tasmanian Caulerpa sea grape species: C. geminata, C. hodgkinsoniae, C. sedoides, and C. simpliciuscula, and quantitatively evaluated the palatability profiles of these species with commercially available C. lentillifera. Initial palatability was assessed through a hedonic human sensory evaluation, followed by quantitative instrumental sensory evaluation of tastes and volatile organic compounds using an electronic tongue (e-tongue) and headspace solid-phase microextraction gas chromatography–mass spectrometry (GCMS). The hedonic human sensory evaluation found three species to have a positive overall liking of approximately seven out of nine, while the fourth species, C. hodgkinsoniae, was significantly less liked overall. This initial evaluation found that the attributes of taste and texture were most influential in driving the separation in overall liking between C. hodgkinsoniae and the other, more palatable Tasmanian species. However, the e-tongue found few differences among the tastes of the five species, with most of the significant differences being small in magnitude, and as such the non-volatile component was unlikely to be the reason why C. hodgkinsoniae was disliked. Analysis with GCMS, however, found significant differences among the five species, indicating that the aroma profiles of these seaweeds play an important role in their palatability and hence potential culinary acceptance. Overall, our results highlight the potential for the Tasmanian sea grape species C. geminata, C. sedoides, and C. simpliciuscula as comparable to the benchmark for edible species of Caulerpa, C. lentillifera, given their positive hedonic human sensory evaluation in combination with comparable flavour profiles determined instrumentally by e-tongue and GCMS.