Proximate composition and nutritional profile of by‐products from green urchin and Atlantic sea cucumber processing plants

Summary Proximate composition, amino acid and fatty acid profiles, and mineral and vitamin contents of by‐products from Atlantic sea cucumber ( Cucumaria frondosa ) and green urchin ( Strongylocentrotus droebachiensis ) processing plants were investigated. Results showed that sea cucumber viscera, urchin digestive tract (UDT) and non‐commercial grade gonads contained 4.5–14.4% total proteins and 1.9–4.6% lipids (wet weight basis). They were rich in essential amino acids with values of about 36% of total amino acids. Samples were also rich in polyunsaturated fatty acids (44% of total fatty acids) and showed high content in EPA (∼17% of total fatty acids), but low DHA level (0.2%) was observed. In terms of vitamins content, UDT showed highest retinol and alpha‐tocopherol contents when compared to other marine samples. Results showed that by‐products from echinoderm processing plants contain various nutritious components with levels generally comparable even better than their edible counterparts, and efforts should be invested to valorise these biological wastes in a world context of rarefaction of nutritional marine resources.