Physicochemical properties of whole pumpkin (Cucurbita maxima) flour

Abstract

This study reported on the physicochemical properties of whole (innards, seeds and rinds) pumpkin flours in terms of the effect of particle size on water absorption capacity, oil absorption capacity, emulsion capacity, emulsion stability, paste density and paste viscosity of pumpkin flour. Two types of whole pumpkin flour were studied i.e. boiled pumpkin flour (BPF) and raw pumpkin flour (RWPF). Both types of flour were prepared in four different particle size i.e. 63 μm, 125 μm, 250 μm and 500 μm. Proximate analysis was also carried out on BPF with the particle size of 250 μm. Proximate analysis showed that BPF was high in carbohydrate and crude fiber content but low in crude protein and crude fat. This study found that particle size and the type of flour affected the physicochemical properties and pasting properties of whole pumpkin flour but not in emulsifying properties. It was found that both water absorption capacity and oil absorption capacity of BPF were higher than that of RWPF. For the emulsion activity and stability, BPF and RWPF were not influenced by particle size of flour. The paste density of BPF increased with an increase in flour particle size and an increase in paste concentration. The viscosity of cold paste, hot paste and hot paste after 30 minutes holding at 95° C for both BPF and RWPF increased as the particle size and the paste concentration increased. The viscosity of RWPF paste was higher than BPF paste. This study showed that whole pumpkin flour was suitable to be used as thickening agent as well as dough ingredients.