Development of purple basil ( Ocimum basilicum L.) sherbet fortified with propolis extract using response surface methodology

The aim of this study was to develop a novel purple basil sherbet fortified with propolis extract. The levels of the purple basil ( Ocimum basilicum L.) aerial parts (leaves, flowers and stems) (200–300 g/L), propolis extract (48–72 mg/100 mL) and infusion time (30–40 min) on total phenolic content (TPC), antioxidant activity (FRAP, DPPH, CUPRAC methods), color parameters ( L*, a*, b*, C*, h° ) and sensory properties were investigated by using Box-Behnken design. According to the model, the optimized values for the propolis extract concentration, purple basil concentration and infusion time were 58.66 mg/100 mL, 300 g/L and 40 min, respectively. Moreover, antimicrobial activity of the beverage samples against Bacillus subtilis , Escherichia coli , Salmonella Enteritidis, Lactiplantibacillus plantarum , Saccharomyces cerevisiae , Schizosaccharomyces pombe , Aspergillus niger and Penicillium roqueforti was also determined.