Seaweeds, spices, condiments and other foods: composition, uses, quality, safety and storage.
Raw ginger is almost 79% water. Per 100 g it provides about 80 calories, 17.8 g carbohydrate, 2 g fiber and 1.8 g protein, but a realistic 10 g piece is only about 8 calories. Ground ginger is concentrated at roughly 335 calories and 14.1 g fiber per 100 g, yet a teaspoon weighs only a few grams.
Nutritional yeast is yeast that has been grown, inactivated and dried for use as food, usually as flakes or powder with a savory, umami flavor. It is not active baker’s yeast and will not make dough rise. A USDA survey reference provides about 40.4 g protein and 26.9 g fiber per 100 g, but a 10 g sprinkle is only about 4.0 g protein and 2.7 g fiber. Vitamin content varies dramatically depending on fortification.
Nutritional yeast is protein-dense, but vitamin B12 should never be assumed from the product name alone. A USDA survey reference provides about 40.4 g protein per 100 g, roughly 4 g in a 10 g serving. For B12, NIH lists several fortified brands at about 8.3–24 mcg per roughly 1/4 cup, while unfortified products may provide no reliable B12. Check the Nutrition Facts label every time.
Maca is the enlarged underground hypocotyl/root of an Andean Brassicaceae plant, usually sold dried and powdered. Analyses of dry maca commonly find roughly 55–73% carbohydrate, 9–21% protein, 8–26% fiber and under 3% fat, but a 5 g spoonful contains only a small fraction of those per-100-g amounts.
Spirulina is a cultivated cyanobacterium, not a marine macroalga, and dried powder is especially concentrated in protein. Seaweeds such as nori, wakame, and kombu are richer in structural fiber and marine minerals, with iodine ranging from modest in nori to extremely high in some kombu.
Edible seaweeds include red, brown, and green species with very different profiles. Dried seaweeds are generally low in fat and rich in fiber and minerals; red nori can be relatively high in protein, while brown wakame and especially kombu tend to contain more iodine. The species name matters far more than the word “seaweed.”
Nori is a red seaweed and wakame is a brown seaweed. In one dry-matter study, nori contained about 32% protein versus 10% in wakame, while wakame had more fiber. Iodine also tends to be higher in wakame: one commercial survey measured 94–185 mcg/g versus 29–46 mcg/g in nori.
Seaweed has no single iodine value. One commercial analysis found 29–46 mcg/g in dried nori, 94–185 mcg/g in wakame, and 241–4,921 mcg/g in kombu. Species, location, growth stage, season, and processing all matter; some brown kelps can exceed the U.S. adult upper limit with less than a gram.
Commercial spirulina is dried biomass from Limnospira/Arthrospira cyanobacteria, not a marine seaweed. USDA reference data provide about 57.5 g protein and 28.5 mg iron per 100 g, but a 7 g tablespoon-sized amount gives roughly 4 g protein and 2 mg iron. It is not a reliable vitamin B12 source.
Dried spirulina is highly concentrated in protein: the USDA reference contains 57.5 g per 100 g and reviews often report roughly 50–70% dry weight. A 7 g serving, however, provides only about 4 g protein; reaching 20 g would require about 35 g of the reference powder.
Spirulina contains all nine essential amino acids, so it is commonly called a complete protein. That label does not mean its protein is identical in quality to egg, dairy, or soy, or that a spoonful meets protein needs: amino-acid proportions, digestibility, and the amount eaten still matter.
Dried spirulina can contribute iron: the USDA reference contains 28.5 mg per 100 g, about 2 mg in 7 g. Its B12 story is very different. Chemical studies show inactive pseudovitamin B12 predominates, so spirulina is not a reliable source for preventing B12 deficiency.