This review compares conventional acid–alkali and solvent extraction with supercritical fluids, enzymatic hydrolysis, pulsed electric fields, ultrasound, cold plasma, microwave, high-pressure processing, and deep eutectic solvents for recovering bioactives from crustacean by-products. No technology is universally optimal: conventional methods retain advantages in simplicity and maturity, while emerging methods may reduce chemicals or better preserve product quality but face equipment, cost, energy, reproducibility, and pilot-scale constraints. The paper is therefore a map of options and evidence gaps, not proof that one technology is the ‘most sustainable.’
Key findings
- Shells, heads, exoskeletons, and processing streams can supply chitin/chitosan, proteins and peptides, EPA/DHA-rich lipids, astaxanthin, minerals, enzymes, and enzyme inhibitors, but composition and functionality vary by species, season, anatomical fraction, and processing history.
- Acid–alkali and solvent methods remain common because they are simple, high-yielding, and technologically mature, but can damage polymers, consume harsh chemicals, and generate effluent. Enzyme-assisted routes offer selectivity and product quality under mild conditions but add enzyme cost and processing time.
- The authors identify ultrasound-assisted extraction as a near-term pretreatment or process-intensification option, enzymes for higher-value products, and supercritical fluids for lipids and carotenoids. Deep eutectic solvents, pulsed electric fields, and plasma still need more pilot-scale validation.
- Applications span preservatives and functional ingredients, nutraceuticals, wound and drug-delivery materials, biodegradable packaging, wastewater adsorbents, and biostimulants. Most edible-coating and active-packaging systems remain at research or pilot stage and require controls for metals, allergens, microbes, residues, and migration.
Why this matters globally
A biorefinery that recovers several products from shrimp, crab, and lobster residues could reduce waste burdens and diversify revenue in seafood-producing economies. Sustainability, however, cannot be inferred from one reduction in solvent use. Technology choices need comparative mass and energy balances, solvent and enzyme recovery, carbon accounting, life-cycle assessment, techno-economic analysis, safety testing, product specifications, and regulatory pathways before industrial environmental benefits can be claimed.
Thai researcher contribution
Akanksha R. Gautam, Soottawat Benjakul, Rattikarn Boonchoosri, and Avtar Singh are affiliated with Prince of Songkla University’s ICE-SSI, while Nilesh Nirmal is affiliated with Mahidol University’s Institute of Nutrition. Publisher CRediT assigns Gautam original drafting, software, data curation, formal investigation, and validation; Benjakul data curation, supervision, and review/editing; Boonchoosri software, validation, and review/editing; Nirmal data curation, formal investigation, validation, and review/editing; and corresponding author Singh conceptualization, investigation, supervision, and review/editing. Thai institutions therefore anchor the conceptual, evidence-synthesis, and supervisory work.
Limitations to consider
No search or selection protocol is reported, preventing assessment of completeness, selection bias, or the quality and risk of bias of included studies. Performance estimates come from heterogeneous feedstocks, pretreatments, scales, solvents, and outcomes, so they cannot be directly compared or pooled as a single effect. Much of the evidence remains laboratory-scale and prioritizes yield or characterization over consistency, cost, energy, solvent recovery, and long-duration operation. The review conducts no new LCA, techno-economic analysis, or safety testing, so it cannot establish that methods labelled ‘green’ outperform conventional processes in real plants.
Verify the original sources
International Journal of Molecular SciencesRead the original review in the International Journal of Molecular Sciences↗DOI: 10.3390/ijms27156959