Effect of extraction method and thermal processing on retention of bioacvtive compounds of pomegrante (Punica granatum) (cv. Bhagwa) juice

Abstract

The effect of juice extraction methods (from arils and halved fruits), temperature (70, 80, 90 and 100̊C) and thermal processing time (2, 5 and 10 minutes) on quality of the pomegranate (Punica granatum L.) juice has been studied. The quality parameters studied included biochemical parameters such as ascorbic acid, total anthocyanin content, total phenolic compounds, antioxidant capacity, TSS, and acidity. The color, microbial, and sensory quality was also evaluated. The results revealed that thermal treatment reduces important bioactive compound with increase in temperature and time of processing. The thermal processing at 80 ̊C for 5 min. found to be suitable for reducing microbial load to below detectable limits and maintaining sensory quality up to 7.91 on ten point hedonic scale. The juice extracted from halved fruits was found to be nutritionally rich than juice extracted from arils in terms of antioxidant capacity, ascorbic acid, total phenolic compounds, total anthocyanin and color value a*. The retention of antioxidant capacity, total phenolic compounds,total anthocyanin content, ascorbic acid and color for thermal processing at 80 ̊C for 5 minutes for juice extracted from halved fruits was 22.68 mg/100ml AAE, 2189 mg/l GAE, 3.18 mg/100 ml, 18.33 mg/100 ml and 37.05 respectively.