To reduce imported products dependency, we need to concern the substitution of wheat to alternative carbohydrates sources, in particular cassava starch is considerable. Cassava starch has low expansion ability in baking process and produce rough texture at the end result. Regarding to these, it is considerable to modify cassava starch to raise its expansion ability for baking process. One of common way to modify cassava starch is by using UV irradiation.
Modification using UV were arranged in constant state along the irradiation. In this research we use UV-A. with temperature 30,5 oC and light intensity 3500 lm/m2. Submersion of the starch in 1% lactic acid for 30 minutes were conducted prior to the UV-A irradiation. The research were done with varying UV-A irradiation time and water content of the starch along the irradiation. The UV-A irradiation time varied in 7, 8, 9, 10, and 11 hours. The water content variation used are 12,5%, 20%, 30%, 40%, and 53%.
The result shows that the best modification for cassava starch by using UV-A irradiation was reached after irradiation for 10 hours after the starch were submersed in 1% lactic acid for 30 minutes and the water content along the irradiation was 40%. This best result was reached for UVAL 1040 starch. The baking expansion ability value of UVAL starch 1040 is 10.20 ml/g, the force needed to crush the end product is 22.29 N, amilose content is 29.77%, and pH 2.41. UVAL 1040 starch has paste viscosity of 371 centipoise, from FTIR result shows that starch UVAL 1040 are having carbonil compound and carboxil compound in wave number 1651 cm-1 with transmittance of 16%, and observation of starch granular structure shows that UVAL 1040 starch were having size reduction prior to the UV modification if we compare it to manufactured starch.
