Determination of the physicochemical, bioactive, rheological and sensory properties of pestil produced using different flours and optimization of its formulation

In this study, a softer dried fruit roll up (pestil) was produced using different concentrations of wheat, corn and potato flours, which received high sensory acceptance scores and had low-HMF content. Simplex lattice mixture model technique with which wheat, corn and potato flours percentages (between 0-12%) were determined was used to study the some physicochemical, bioactive, rheological, nutrition and sensory properties of pestil. In addition, optimization variables of the most-liked product were determined according to the sensory scores. Corn and potato flours incorporated into the formulation along with wheat flour were found to significantly affect the physicochemical, bioactive, rheological and sensory attributes of the end product. The dry matter, protein, L*, b* values of the pestil samples were significantly reduced with increased corn and potato flour proportions (p<0.01 and p<0.05). On the other hand, a*, moisture values were significantly increased when corn and potato flour proportions were increased (p<0.01 and p<0.05). It was determined that the increased potato flour proportion resulted in the formation of more viscous herles (p<0.01) The HMF content of the samples were determined to be below 50 mg/kg. The highest HMF was observed in the 13th sample with 6.60 mg/kg; and the lowest in the 4th sample with 1.42 mg/kg. Total sugar contents were between 33.34% and 48.55%, and the most dominant sugar was found to be saccharose. It was observed that the total phenolic contents of the samples varied between 783.0-2154.8 mgGAE/kg and this variation was significant (p<0.01 and p<0.05). Significant increases in the antioxidant properties were also determined in the pestil samples (p<0.01 and p<0.05). Generally, the sensory properties of the pestil samples significantly decreased when potato flour proportion was increased (p<0.05), and corn and wheat flours exhibited similar sensory properties. The optimization of the samples was done according to the sensory analyses, and it was determined that the best pestil formulation can be produced by incorporating 4.69 g wheat flour and 7.39 g corn flour per 100 g. Moreover, the best formulation in pestil production for celiac patients was determined to be 10.69 g corn flour and 1.39 g potato flour per 100 g. In conclusion, the pestils produced using corn flour exhibit similar results with the control group (wheat flour-containing samples) and they could be conveniently used for pestil production; while potato flour should be incorporated in very small percentages.