A Comprehensive Review on Seaweed Preservation Techniques: Impacts on Nutritional Quality, Safety and Shelf Life

Seaweeds are important marine resources that contain a great variety of beneficial compounds, including protein, essential fatty acids, vitamins, minerals, fibers, and bioactive compounds such as polyphenols and carotenoids. Nutritional, functional, and industrial properties of these marine algae make them highly applicable to culinary, nutraceutical, pharmaceutical, agricultural, and cosmetic sectors. Seaweeds are perishable as their quality gets highly influenced under certain conditions, such as high moisture content, enzymatic activity, and microbial presence. Parameters such as water activity, lipid indices, total volatile base nitrogen, microbial load, pathogen detection, pH, and sensory properties are used to determine the loss of quality and product stability over time, helping in the determination of the shelf life of seaweed during the post-harvest storage period. To extend the shelf life, several preservation methods have been explored. Traditional methods include sun drying, oven drying, salting, and fermentation, which provide easier and lower-cost conditions, but sometimes cause a compromise in quality. Modern techniques like high-pressure processing, pulsed electric fields, modified atmosphere packaging, and irradiation appear as solutions with lower loss of quality, higher nutrient retention, microbial safety, and sensory attributes. This review critically evaluates post-harvest deterioration mechanisms, quality assessment parameters, traditional and advanced preservation techniques, their impact on shelf life and product quality, and current consumer perceptions to promote sustainable utilization of seaweeds in response to rising global demand.