Production of natural colorant from peach pomace by eco-friendly methods

Within the scope of the thesis; The aim of this study was to investigate the possibilities of using carotenoids in peach pomace as natural food colorants and optimization of carotenoid extraction conditions by enzyme assisted ultrasonic extraction using the response surface method (RSM). For this purpose, in the optimization of extraction conditions, the sample amount (1-3 g), enzyme rate (0-10%), temperature (20-60°C) and time (10-60 min) were optimized using the independent variables. Response selection was determined according to the maximum total carotenoid content and the maximum b* (yellowness) color value. The optimum point determined as suitable extraction conditions; It was carried out in 1.00 g sample, 8.50% enzyme, 45.18 ºC temperature, 50.36 minutes and it was determined that the highest value in terms of carotenoid amount was obtained by ultrasonic method (0.241±0.00 mg/kg β-carotene). Also, peach pulp extracts were produced in one step by conventional (enzymatic extraction without ultrasound) and ultrasonic methods and some physical and chemical properties of the extracts; total carotenoid, carotenoid distribution, total phenolic substance, antioxidant capacity (ABTS and FRAP), pH, total acidity, water-soluble dry matter and color values were compared. In addition, the possibilities of using the extracts produced under the specified conditions as natural colorants in lemonade drinks were investigated. The extracts were added to the prepared lemonades at specific concentrations (0.1%; 0.2%; 0.3%; 0.4%); evaluated by physical and chemical analysis. In the study, it was determined that the ultrasonic method in peach pulp extraction is faster and more effective than the traditional method, and the extracts obtained can be used in foods such as lemonade with their natural coloring and natural preservative properties.