Optimization of osmotic dehydration of shatavari roots

Abstract

Shatavari roots (Asparagus racemosus) is an indigenous traditional medicinal plant. Shatavari roots are rich in phytochemicals such as Saponins, Flavonoids, Alkaloids, Phenol and Tannin content. Osmotic dehydration is a preservative method that helps in retaining valuable phytochemicals, reducing the moisture content and inhibit the growth of microorganisms which produces shelf-stable products and can be used during off- season. The results of this study consist of osmotic dehydration of shatavari roots followed by its convective drying. The process parameters considered for the study were osmotic concentration (50-70°Brix), osmotic temperature (40-60 °C), stirring speed (0-60 rpm) at a constant immersion time (180 min) at constant syrup to shatavari root ratio (4:1) and drying temperature and evaluated their effects on mass transfer properties, drying kinetics, physical, chemical, phytochemical and sensory properties. Optimization of process parameters were done by Design Expert software 13. The optimum process parameters obtained were: 60 °Brix of sugar concentration, 50 °C of osmotic solution temperature and 60 rpm of stirring speed for water loss (42.03%), solid gain (5.77%) and mass reduction (36.27%). Drying temperature (50-70 °C) had affected significantly at 5% level the drying rate and final quality of the product.