Effect of processing techniques on biochemical, mineral, heavy metal and microbial load in edible seaweeds and seawater parameters of western Bay of Bengal

Abstract

Seaweeds are promising resources of the coastal zone and can serve as an effective breakthrough in seafood owing to the causes of food security. Hence, challenges in its processing are of utmost importance with respect to its consumption. The present study aims to investigate the effects of various food processing methods (unwashed, washed, soaked, and boiled) on biochemical, mineral, and microbial loads on two selected seaweeds (Ulva lactuca and Gracilaria corticata) sampled seasonally from the Visakhapatnam coast of Andhra Pradesh during 2018–19. The analyzed seawater parameters, nutritive and anti‐nutritive values, were at their maximum during the monsoon, followed by the post‐monsoon and the pre‐monsoon. Biochemical parameters showed an increased concentration in boiled U. lactuca and G. corticata. Minerals, heavy metals, and microbial load results have shown a decreased concentration in the order of unwashed > washed > soaked > boiled in both species. This has been proven through the bioconcentration factor for both species seasonally. All the results are well within the Recommended Dietary Intake as per FAO/WHO. Pearson's correlation coefficient has proven post‐monsoon to be the best season for the harvest of seaweeds. Principle component analysis biplots computed for unwashed, washed, soaked, and boiled seaweeds have shown a positive relationship with mineral and toxic metals in unwashed and washed G. corticata in contrast to U. lactuca. This study ascertains the fact of using boiled and soaked G. corticata and U. lactuca (in all forms except unwashed) for the development of new healthy seaweed‐based foods in changing climate scenarios.