Utilization of Sorrel/Roselle (Hibiscus sabdariffa L.) Nectar in Stirred Yoghurts: Physicochemical and Sensory Quality

摘要

This first study investigated the effects of sorrel/roselle (Hibiscus sabdariffa L.) nectar on physicochemical and sensory quality of stirred yoghurts. Sorrel calyces were hot-water processed at 60°C for 3.5 h, cooled treated with pectolase for puree and processed into nectar. To plain yoghurt, nectar of 60°Brix or 67°Brix was added at 27 and 33% level (v/v). Focus groups guided product development. Yoghurt with 33% of sorrel 60°Brix nectar with 0.6% sorrel flavor extract was rated as liked moderately to very much in overall acceptability. This hedonic scoring of yoghurt with 33% of sorrel was not influenced by the reading of an extract on the nutritional and health benefits of sorrel by panelists. Yoghurt had ?L? 59.00, ?C? 10.56, hue° 14.24, pH 3.81, 23.00°Brix, 0.19% lactic acid and consistency 0.56 mm sec 1. On storage at 4°C for 4 weeks, yoghurt became less red and chromatic, more viscous and acidic and had higher microbial growth. A yoghurt serving was a good source of protein.