Main Article Content
This study was conducted with the aim of testing the effectiveness of the Roselle flower plant as an antioxidant and as an anti-growth agent for microorganisms and its use in the manufacture of dairy products, It was bought from the local market and crushed and dried as soon as it reaches the laboratory. The content of total phenolic compounds was determined by using high-performance liquid chromatography (HPLC) device to estimate the concentration of some of the active compounds: Catechine, Gallic acid, Keamferol, Qurcetine and Rutin. A GC.MS gas chromatography-mass spectrometer was used to total diagnose the volatile active compounds. The antioxidant activity was estimated in the alcoholic extract and the aqueous extract of the samples under study. Where it is noticed that the aqueous extract of Roselle flowers has the ability to free radical scavenging and the total antioxidant capacity of the aqueous extract of Roselle flowers reached 29.39%. The aqueous and alcoholic extracts of Roselle flowers showed clear contrast in the inhibition of the pathogenic bacteria under study (S. aureus, E.coil). One of the fermented dairy products, which is yogurt, was chosen to study the effect of adding aqueous extracts to the flowers of the Roselle plant under study. The antioxidant activity of the fermented milk was estimated before and after the addition. A sensory evaluation was performed for yogurt containing 3.0% of the plant extract. The results of the evaluation showed consumer acceptance. No significant differences were showed between the manufactured product and the control treatment in terms of flavor, taste, texture, acidity and external appearance.