ABSTRACT GALICIA, ALOJA D., Department of Resource Engincering and Agricultural Mechanization, College of Engineering and Computer Studies, Pampanga State Agricultural University, PAC Magalang, Pampanga. June 2023. "Optimization of Spray-Dried Tamarind (Tamarindus indica L) Leaves as a Food Additive" Adviser: Dr. Mari Rowena C. Tanquilut This study was conducted to optimize the spray drying of tamarind leaves using response surface methodology. The effect of the factors such as inlet temperature of 89 °C, 94°C, and 99C; concentration ratio of 1:3,1:4, and 1:5; and maltodextrin percentage of 9%, 14%, and 19% by weight on the response variables such as moisture content, drying capacity, and recovery rate of the product were evaluated. The experimental test consisted of 17 runs and 3 validation runs. The results showed the Box-Behnken three- level three-factor fractional design with response surface methodology was found to be efficient for optimizing the operational parameters of the spray drying process for tamarind leaves at inlet temperature of 90 C, concentration ratio of 1 :3.33 (leaves:water), and maltodextrin percentage of 11.54 having a moisture content of 4.90%, drying capacity of 6.61 kg/hr, and recovery rate of 0. 16 kg/hr. Phytochemical screening analysis was done using Ferric chloride reagent (FeCl;) and Dragendorff's reagent and revealed that the ethanolic leaf extract of tamarind was proven to have flavonoids, phenols, and alkaloids. A toxicity test was done on six ICR mice by subjecting the product orally and was found to be non-toxic, safe to consume, and potential to be developed as a food. Additionally, one hundred grams of sample was used in determining the nutrient composition of spray-dried tamarind leaf powder and the results showed that about 4.94% moisture, 1.01% ash, 0.24% fat, 91.30% carbohydrates, and 2.50% of protein were present. Moreover, sensory evaluation showed that the spray- dried tamarind leaf powder was generally acceptable and was preferred by the panelists as a flavor enhancer. Furthermore, a shelf-life analysis was also done by storing the product for 30 days. It was revealed that there was no difference in the color, texture, aroma, and smell from day l up to day 30 and it could be stored for longer than 30 days. Lastly, the product was found to be economically viable from the results of the cost and return analysis as the product could be sold at P120 per 50g of powder. Based on the results, spray drying of tamarind leaves could be optimized at an inlet temperature of 90 C, concentration ratio of 1:3.33 (leaves:water), and 11.54% of maltodextrin and could be utilized as a food additive. Further studies may be done on the nutraceutical properties of spray-dried tamarind leaf powder.