Sensory and volatile analysis of sea urchin roe from different geographical regions in New Zealand

Roe from the sea urchin Evechinus chloroticus collected from locations in the North (Mathesons Bay) and South (Doubtful Sound) of New Zealand was characterised according to physical characteristics, sensory properties, and volatile composition. Objective assessment of roe sensory properties (appearance, odour, taste, flavour, texture, and aftertaste) was carried out by a trained sensory panel using descriptive sensory analysis. Proton transfer reaction-mass spectrometry (PTR-MS) was used for headspace analysis of roe, and data were collected over the mass range m/z 22–180. Sea urchins from the Northern population were significantly smaller, and had a lower roe index than those from the Southern population. Roe from Northern sea urchins were rated higher for the attributes of marine, seafood and sharp odour, bitter taste, herbaceous and metallic flavour, astringent texture, and metallic, bitter, and duration of aftertaste than roe from Southern sea urchins, which were rated higher for dairy odour, sweet taste, dairy flavour, moisture content and mouth coating. E. chloroticus roe was also differentiated based on gender by 26 sensory attributes. Volatile analysis significantly discriminated between roe from Northern and Southern sea urchins by 35 mass ions, and between genders of Southern sea urchins by five mass ions.