Formulation of Cookies Incorporated with Duckweed Powder and Evaluation of Its Physicochemical, Nutritional, Functional, Microbial, and Sensory Properties

Duckweed, a largely underexploited aquatic plant from the family Lemnaceae, is notable for its high protein content, encompassing all essential amino acids, and its abundance of micronutrients. This study explored the feasibility of incorporating duckweed powder into cookie formulations. Based on preliminary investigations, Lemna perpusilla and Spirodela polyrhiza were selected for the production of duckweed powder, which was subsequently assessed for its physicochemical, nutritional, and functional characteristics. Four cookie formulations were then prepared by substituting wheat flour with duckweed powder at levels of 10%, 20%, 30%, and 40%, alongside a control sample composed entirely of wheat flour. Sensory evaluation was performed using a 9-point hedonic test with 40 semi-trained panelists and identified the most preferred cookie, which was further assessed. According to proximate analysis, the selected cookie showed significant differences (p<0.05) from the control, with higher crude protein 12.25±0.02%, crude fat 21.45±0.03%, crude fiber 10.25±0.03%, crude ash 3.76±0.04%, and digestible carbohydrate 47.23±0.10%. The cookie provided 430.98±0.05 kcal/100g, with 22.43±0.04% sugar, 0.74±0.02% salt, and 1.64±0.03% total dietary fiber. Mineral content was significantly higher (p<0.05). Functional properties such as total phenolic content (1.62±0.03 mgGAE/g), flavonoid content (282.05±0.01 mgCAT/g), DPPH radical scavenging activity (212.36±1.20 mM TE/g), and α-amylase inhibition (IC₅₀ 2.26±0.02 (μg/mL) were also high (p<0.05). Microbial levels remained within safe limits for one month, and all chemical and safety standards were met. The findings suggest that duckweed powder can serve as an effective partial replacement for wheat flour, enhancing both the nutritional profile and functional characteristics of cookie formulations.