Effect of varied spray drying parameters on physicochemical, micrometric and microstructural characteristics of pear powder employing response surface approach

Purpose Currently, there is a great demand for those food products that are easy to prepare or ready for direct consumption. Making pear fruit/juice available round the year is desirous owing to pears' high-nutritional value and specific pleasant taste. Pear is, however, a seasonal fruit and under ambient conditions has a limited shelf life rendering it available as fresh fruit for a specific period. Design/methodology/approach The study aimed to optimize the spray drying process parameters using response surface methodology for the development of pear juice powder. The process variables included the inlet air temperature of 140-210 degrees C, maltodextrin levels of 4-25%, atomization speed of 11,400-28,000 rpm, feed flow rate of 180-630 mL/hr, and feed total soluble solids (TSS) of 13-30 degrees Brix. The dependent responses were powder yield, solubility, antioxidant activity {% 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity}, dispersibility, hygroscopicity and particle density. Findings Among independent variables, inlet air temperature showed a predominant effect. The optimum processing conditions for the development of pear juice powder with optimum quality were 163.02 degrees C inlet air temperature, 13.50% maltodextrin, 28,000 rpm atomization speed, 390.94 mL/h feed flow rate, and 25.5 degrees Brix feed TSS. Under these optimum conditions, pear powder with desirable properties could be produced. The experimental and predicted values were found to be in agreement, indicating the suitability of the model in predicting optimizing responses of pear powder. Glass transition temperature of pear powder was found to be 36.60 +/- 0.40 degrees C, which is much higher than that of ambient temperature, suggesting better shelf stability. Originality/value The processing of pear fruit has resulted in the increased demand for pear juice powder in both domestic and international markets as a primer of new food products. The optimum conditions obtained in the current study could provide a new insight to the food industry in developing spray-dried pear powder of optimum quality. This can open up a new horizon in the field of food industry for the common masses of Jammu and Kashmir, India.