Optimization of ingredients level for developing yellow passion (passiflora edulis) fruit jam

ABSTRACT This study was carried out to investigate the optimum level of ingredients to develop an acceptable jam product from yellow passion fruit. The jam was developed from fresh yellow passion fruit using four ingredients: sugar, pectin and citric acid of different levels. The different ingredient levels were optimized using response surface methodology (RSM). A uniform precision type Box-Behnken design consisting of three variables in a three-level pattern with 17 runs (with five center points) was employed to optimize the jam to obtain a product with adequate sensory acceptability, especially, overall acceptability. Sensory analysis for appearance, color, flavor, sweetness, taste, texture and overall acceptability was performed. Jam produced under the optimum conditions was subjected to sensory evaluation, and the results were compared with the RSM predictions. Data obtained from RSM were subjected to the analysis of variance (ANOVA) using a second-order polynomial equation. Results showed that the model fit was significant (p < .05) for appearance, flavor, taste, sweetness and even highly significant (p < .01) for texture, color and overall acceptability. There was also a satisfactory correlation between actual and predicted values. Depending on the best sensory score obtained, the optimum ingredient levels were 400 g/kg, 5.24 g/kg and 1 g/kg for sugar, pectin and citric acid, respectively.