Utilization of dragon fruit (Hylocereus polyrhizus) peel and passion fruit (Passiflora edulis) juice for fruit jam development

This study was conducted to utilize dragon fruit (DF) peel (100% blended, 50:50 blended and strips, 50:50 blended with fruit bits) and passion fruit (PF) juice (10, 15, 20% w/w) into dragon-passion jam. Sensory qualities (color, aroma, taste, mouthfeel and general acceptability) were evaluated using a 9-point hedonic preference score. A consumer acceptability test was done to validate the acceptance of the optimum formulation. The optimum formulation (50:50 DF blended peel and fruit bits, 15% PF juice) was bounded by an aroma and taste acceptability score of ≥7 by sensory panelist. Parameter estimates from response surface regression (RSREG) analysis indicated that the utilization of DF peel into dragon-passion jam provided a positive response to color acceptability. It was found that 20.22% PF juice was the maximum level required to attain a predicted color acceptability score of 7.12 (moderately liked) and when exceeding 20.22% the predicted color acceptability of the product decreased. Furthermore, the optimum formulation had a potential to compete in the marketplace with a consumer general acceptance score of 8.35 (liked very much) which was higher than the predicted acceptability score.