The aim of our research was to perform a comprehensive study of ecdysterone (ECD)-containing dietary supplements (DSs). Two analytical methods were optimised according to the expected concentration of the target compounds: quantitation of ECD by liquid chromatography (LC) coupled to diode array detector (DAD), and limit test for 47 World Anti-Doping Agency prohibited by LC coupled with tandem mass spectrometer (MS/MS). For quantitation of ECD, the method was fully validated with outstanding performance characteristics (LOD: 35 µg·g⁻¹, LOQ: 115 µg·g⁻¹, CV% < 5%), resulting in significantly lower LOD and shorter runtime than published previously. For limit tests, a chromatographic method was developed to obtain excellent separation, while MS/MS parameters were optimised to allow the lowest possible reporting limit (RL: 0.6–10 ng·g⁻¹ or mL⁻¹). Twenty-one ecdysterone-containing DSs from ten brands were analysed. In all cases, the measured ECD content was much lower than labelled, and 20% of the samples contained a prohibited substance. The concentration of ecdysterone and contaminations varied randomly from batch to batch. The developed methods help to prevent the use of contaminated or useless DSs.

This study explores the potential of some commercially available plant proteins to increase the protein content of gluten free cookies produced from green lentil flour. Isolates from hemp seed, brown rice, yellow pea, and pumpkin seed were investigated. Cookies were additionally enriched with inulin and matcha tea. Products were characterized in terms of physicochemical parameters (e.g., crude protein content, total phenolics and flavonoids, antioxidant activity, and color). Additionally, technological properties including geometry, baking loss, and texture profile were determined, and a sensory profile test was conducted. The replacement of a quarter of lentil flour with plant proteins increased the protein content (control: 12.4% vs. 15.1–20.4%), but suppressed the polyphenol content, resulting in reduced antioxidant capacity (3.13 vs. 2.14–2.69 mmol TE/100 g). The geometry, texture properties, and color of the cookies were affected by all the proteins investigated. The biggest difference was shown in the case of using yellow pea (YP) protein, which showed the highest browning index (YP: 66.36 vs. 42.63–63.45) and spread ratio (8.38 vs. 5.63–6.39) among the samples tested. The sensory attributes of the cookies, such as tea notes, surface homogeneity, crunchiness, and crumbliness, proved to be negatively affected by the plant proteins, which may be a limitation for consumer acceptance.