Effect of Milk Thistle and Red Sage Addition on the Acceptability and Flavonoid Content of "THISAME" Yoghurt as a Functional Food
Year: 2026
Type: article
Abstract: Background: Non-alcoholic fatty liver disease (NAFLD) is closely associated with dietary patterns and metabolic health. Yoghurt containing probiotics may represent a potential functional food approach because probiotic consumption has been associated with improvements in liver-related biomarkers and metabolic parameters. Milk thistle (Silybum marianum), a source of silymarin, and sage (Salvia spp.) contain bioactive compounds with antioxidant properties and therefore have potential for incorporation into functional food products. Objective: This study aimed to develop "THISAME" yoghurt containing milk thistle and red sage, evaluate its sensory characteristics and acceptability, and determine the nutritional composition and antioxidant activity of the selected formulation. Methods: An experimental study was conducted using a Completely Randomized Design with three formulations and three replications. "THISAME" yoghurt was prepared using milk, yoghurt starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricus), milk thistle extract, and red sage extract. The three formulations consisted of milk thistle and red sage at concentrations of T1 (1.9% and 1.0%), T2 (2.3% and 1.2%), and T3 (2.7% and 1.4%), respectively. Sensory evaluation was performed by 30 semi-trained panelists using colour, aroma, taste, texture, and overall acceptability as evaluation parameters. Data were analysed using the Friedman test followed by the Wilcoxon signed-rank test at a significance level of 5%. The selected formulation was further analysed for nutritional composition, pH, total soluble solids, and antioxidant activity using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Results: Significant differences were observed among formulations for colour (p = 0.007), aroma (p < 0.001), texture (p = 0.009), and overall acceptability (p < 0.001). T2, containing 2.3% milk thistle and 1.2% red sage, showed the highest overall acceptability, with 56.7% of panelists rating it as liked or very much liked. The selected formulation had a creamy-white colour, no noticeable herbal aroma, a slightly perceptible sage and silymarin aftertaste, and a moderately thick and smooth texture. Laboratory analysis showed protein, fat, and carbohydrate contents of 2.02, 3.20, and 19.30 g/100 g, respectively, with a pH of 5.0 and total soluble solids of 17 °Brix. The DPPH assay demonstrated a visible colour change from purple toward yellow, providing qualitative evidence of radical-scavenging activity. Conclusion: "THISAME" yoghurt containing 2.3% milk thistle and 1.2% red sage was the most acceptable formulation among the treatments evaluated and demonstrated measurable nutritional value and qualitative antioxidant activity. The product shows potential as an antioxidant-containing functional yoghurt; however, further studies should quantify silymarin and flavonoid concentrations and antioxidant capacity and evaluate the product's biological effects before specific health claims related to liver protection can be made.
Language: English
Subfield: Food Science
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7204256463