Chemical Characterization, In Vitro Analysis of Functional Properties, and Volatile Profiling of Sixteen Nutraceuticals Marketed as “Superfood”

In recent decades, there has been an increasing consumer demand for the so-called superfoods, accompanied by a growing scientific interest. In our work, sixteen commercial nutraceuticals of different product categories, including powders of cereal grasses, vegetables, fruits, microalgae, an aquatic plant, and herbs, were analyzed to compare their nutritional properties and volatile profile. Some samples, especially spirulina, chlorella, and duckweed powders, were rich in protein; however, their amino acid composition was imbalanced. Spinach, duckweed, and moringa powders exhibited very high ash contents, while sea buckthorn powder was a relatively rich source of lipids. Acerola powder had the highest total phenolic content by far and showed exceptional antioxidant and antibacterial properties in in vitro analyses as well. Aronia and rosehip powders also had high antioxidant potential, while moringa powder exhibited remarkable antibacterial activity. The headspace volatiles of the samples showed significant variations. Terpenes were the major volatiles in herbs, especially in turmeric and ginger powders. High levels of acids were detected in fruit powders. Some compounds were only characteristic of certain products, for example, dimethyl sulfide in beetroot powder, trans-3-penten-2-one in aronia powder, hexadecane in spirulina powder, and turmerones in turmeric powder. These volatiles can be considered botanical markers, which potentially help detect the adulteration of specific nutraceuticals. Overall, this study presents the nutritional and aromatic diversity among various “superfood” powders, highlights their potential application as ingredients in functional foods, and emphasizes the need for regulatory standards to ensure product safety, quality, and consistency in the growing nutraceutical market.