Optimization of mucilage extraction from Sepestan fruit and evaluation of its physicochemical and antioxidant activity

In general, hydrocolloids are a group of additives that play many roles in the food industry such as thickening, gelation and stabilization. Optimization of mucilage extraction from Sepestan fruit was performed using response surface methodology and Box–Benken statistical design. Extraction temperature in the range of 45–85 °C, pH in the range of 4–7, and liquid to solid ratio in the range of 5–15 ml/g as experimental variables were optimized base on different parameters including extraction yield, solubility, water absorption capacity, foam stability, oil absorption capacity, heat emulsion stability, turbidity and free radical scavenging. Results showed that the quadratic polynomial model was the most appropriate model for all the factors studied. Optimized conditions for extraction of Sepestan fruit mucilage (SFM) were determined as extraction temperature 57.49 °C, pH 4 and liquid to solid ratio 6.27 ml/g. In optimum conditions, the values of yield, solubility, water absorption capacity, foam stability, oil absorption capacity, heat emulsion stability, turbidity and antioxidant activity of SFM were determined as 8.83%, 27.30%, 28%, 0.04%, 28%, 443.4%, 0.13% and 36.83%, respectively. In a general conclusion, due to the reasonable yield of mucilage extraction and its pragmatic properties such as proper oil absorption, heat emulsion stability and antioxidant potential, its utilization may be recommended in food and pharmaceutical industry.