Department of Agro Industrial Technology, Faculty of Agricultural Technology, Rajamangala University of Technology Thanyaburi. (RMUTT) Phaholyothin Soi Phaholyothin Road, Thanyaburi, Pathum Thani, Thailand.
Corresponding Author E-mail: wattana@rmutt.ac.th
One useful economic crop which is utilized worldwide is Chinese jujube. It offers both nutritional and therapeutic benefits. Meanwhile, Oolong tea is a semi-oxidized form of tea which has a flavour that falls somewhere between black tea and green tea. Finally, spray-drying is an important technique used in food preservation. This current study sought to assess the most suitable use of Chinese jujube along with appropriate levels of maltodextrin when creating a mixed Oolong tea which incorporates Chinese jujube and is subsequently processed via spray-drying. Oolong tea served as the control sample, while evaluations were carried out on 60%, 70% and 80% blends of Chinese jujube with maltodextrin which served as a carrier agent at concentrations of 20 g, 30 g, 40 g and 50 g. These solutions underwent spray-drying where the respective inlet and outlet temperatures were 190°C and 80°C. An evaluation of the physico chemical, microbiological and sensory evaluation were performed. There was evidence of an increase in the total phenolic compounds, whereas in contrast there was a decline in antioxidant activity. L* and +a* showed no statistically significant difference, although for +b* a statistically significant difference was found. For products with mixed Chinese jujube and Oolong tea, the moisture, water activity and pH values were shown to be lower, although there was an increase in total soluble solids. In the evaluation, flavour and overall acceptability for Treatment 4 (80% Chinese jujube) achieved the highest respective ratings at 8.17 and 8.13 on the 9-point scale. This demonstrates that spray-drying can be beneficial in the context of powdered particles. The combination of Chinese jujube and powdered Oolong tea provides good antioxidant properties and offers strong potential for applications in the food sector.
Chinese jube; Maltodextrin; Oolong tea; Spray drying; Ziziphus jujuba Mill