Effect of particle size reduction on physicochemical properties of ashgourd (Benincasa hispida) and radish (Raphanus sativus) fibres.

The present work was aimed at studying the effect of particle size reduction on the physicochemical properties of ashgourd and radish fibre. Both the fibres after extraction of juice were dehydrated and subjected to granulometry to obtain 30, 60 and 100 mesh particles. The yield was more for 60 mesh particles. The image analysis as well as microstructural analysis of particles by scanning electron microscopy showed distinctive properties. The 30 mesh particles of ashgourd and radish fibre contained 66.35% and 53.11% total dietary fibre while the soluble fibre content was 22.76% and 17.75%, respectively. The fibre content decreased by 7-8% with decrease in particle sizes. The values of water holding capacity, water binding capacity, oil binding capacity, swelling power and cation exchange capacity also decreased with the decrease in particle size. However, the particle density values increased with the decrease in particle size. These results underline the influence of the physical structure of the fibre on the physicochemical properties.