Abstract

       This research was conducted to optimize the formula to produce pineapple paste and gluten-free pie products. The seven formulas of the pineapple paste consisting of pineapple residue (70-100%), pineapple juice (0-30%) and sugar (0-30%) were studied using Mixture Design. The properties and sensory evaluation by untrained panelists were investigated. The results showed that the pH of pineapple paste tended to decrease when the amount of pineapple juice increased. Apparently, the total soluble solid and brightness of pineapple paste varied directly as the amount of sugar. An appropriate formula of pineapple paste was 75% pineapple residue, 5% pineapple juice and 20% sugar, respectively. This formula had the highest score for all attributes. Next, the nine formulas of gluten-free pie products consisting of mixed flour (60-70%), salted butter (20-40%) and pineapple residue (0-10%) were studied using Mixture Design. The properties and sensory evaluation by untrained panelists were investigated. The results indicated that weight loss of pies varied directly with the amount of butter. The hardness and the brightness of pies varied directly with the amount of mixed flour. Obviously, a suitable formula of gluten-free pie product was 70% mixed flour, 20% salted butter and 10% pineapple residues, respectively. This formula had the highest score for all attributes. In conclusion, utilization of pineapple residue helps provide value-added on agricultural by-products in gluten-free foods.

Keywords: Pineapple Residue, Pie, Gluten-free