Journal of Food Processing & Technology

Abstract

Formulation of Vegetable Soup Mixture Using Physically Modified Sweet Potato Starch as a Thickener

Senanayake SA, Ranaweera KKDS, Gunaratne A and Bamunuarachchi A

Potential application of modified sweet potato starch as a substitute thickener for corn starch was studied using native starches extracted from five different cultivars of commonly available cultivars in Sri Lanka. Physicochemical properties (SP, WSI, pasting, gelatinization) and digestibility of native and modified (heat – moisture treated, 30% moisture, 85°C for 6 hrs) starches were analysed. Modified Swp3 (Wariyapola white), Swp4 (Pallepola)and Swp5 (Malaysian) starches were selected based on the favourable condition exhibited in the required physical and chemical properties and applied in the vegetable soup formula and tested against corn starch added samples for viscosity difference and sensory attributes. Viscosity of the reconstituted soup powder and sensory analysis showed that Swp4 and Swp5 had significantly high level (p<0.05) and the average rank for mouth feel (taste), texture and overall acceptability was significantly high (p<0.05) in Swp5 added samples. Shelf life studies ensured 6 months stability with negligible level of moisture increase and total plate count in air tight polypropylene packages at ambient temperatures (28-31°C). Results of this study revealed a possibility of applying physically modified Swp4 and Swp5 starches as a substituent food ingredient for corn starch to improve the thickness of food products.