Microbial and Heavy Metal Analyses of Commercially Available Sea Moss and Sea Moss Products

Sea moss has gained popularity as a functional food, yet information on the microbial quality, physicochemical characteristics, and heavy metal concentrations of commercially available products remains limited. This study evaluated 66 sea moss products purchased from major online retailers in the United States, including 53 dried sea moss products and 13 sea moss gels. Water activity ranged from 0.33 to 0.76 (0.59 ± 0.11) in dried sea moss and from 0.74 to 1.00 (0.98 ± 0.07) in gels. Sea moss gels exhibited substantial variability in pH (2.71-7.05) and °Brix (0.80-46.10). Mean total plate counts were 4.30 and 3.92 log CFU/g in dried sea moss and gels, respectively, while mean yeast and mold counts were 3.23 and 3.60 log CFU/g. Presumptive Bacillus and Staphylococcus spp. were recovered from both product types, while presumptive Escherichia, Salmonella, Listeria, and Vibrio spp. were detected less frequently. Molecular characterization of selected isolates identified Bhargavaea, Exiguobacterium, Staphylococcus, Salmonella, Cronobacter, Bacillus, and Escherichia spp.; Listeria and Vibrio spp. were not identified among isolates yielding interpretable sequence results. Arsenic, cobalt, and mercury were detected in dried sea moss, whereas arsenic and cobalt were below the limits of detection in the gels and mercury was detected at trace concentrations. Substantial variability in microbial and physicochemical characteristics among commercial sea moss products highlights the need for additional research and evidence-based guidance to support appropriate processing, storage, and handling practices.