{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T02:17:02Z","timestamp":1788229022259,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>The sustained decline in Japanese Manila clam landings has increased interest in complementary bivalve food resources. This descriptive study compared one pooled soft-tissue analytical sample from each of four sources: Ruditapes philippinarum from Akkeshi, Mangoku-ura, and a commercial Chinese-origin source, and the warm-water clam Ruditapes variegatus from Ishigaki Island. Each pooled sample comprised approximately 250 g of soft tissue from at least 40 individuals; independent lot-level biological replication was not available, so no inferential statistical comparisons were made. Proximate composition, amino acids, taurine, vitamin-related compounds, minerals, and fatty acids were analyzed, and mitochondrial cytochrome c oxidase subunit I (COI) sequencing together with morphology confirmed the Ishigaki material as R. variegatus. Wet-weight total amino acid contents were 8.670, 6.800, 6.135, and 5.555 g\/100 g in the Akkeshi, Ishigaki, Mangoku-ura, and Chinese-origin pooled samples, respectively. After normalization, total amino acid contents ranged from 507.0 to 559.4 mg\/g dry matter and from 829.1 to 850.0 mg\/g protein, indicating that much of the wet-weight contrast reflected differences in tissue moisture and protein concentration. Adult-reference amino acid scores ranged from 97.1 to 100 across the four composites. The Akkeshi pooled sample also showed comparatively high taurine and vitamin A-related values. Sea surface temperature and satellite chlorophyll-a data were used only to document source-region environmental context and were not treated as causal predictors of composition. Within the limits of this pooled-sample survey, the food-composition profile of taxonomically verified Ishigaki R. variegatus supports further replicated evaluation of this species as a complementary clam-like food resource.<\/jats:p>","DOI":"10.3390\/foods15173038","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T04:24:03Z","timestamp":1788150243000},"page":"3038","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nutritional Profiles of Ruditapes philippinarum and the Complementary Food-Resource Potential of the Warm-Water Clam Ruditapes variegatus"],"prefix":"10.3390","volume":"15","author":[{"given":"Tomoyasu","family":"Yamazaki","sequence":"first","affiliation":[{"name":"Toyo Institute of Food Technology, 23-2, 4-Chome, Minami-Hanayashiki, Kawanishi 666-0026, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0421-2812","authenticated-orcid":false,"given":"Kenji","family":"Okoshi","sequence":"additional","affiliation":[{"name":"Toyo Institute of Food Technology, 23-2, 4-Chome, Minami-Hanayashiki, Kawanishi 666-0026, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"ref_1","unstructured":"Ministry of Agriculture, Forestry and Fisheries of Japan Fisheries and Aquaculture Production Statistics Annual Report, Ministry of Agriculture, Forestry and Fisheries of Japan. 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