Effect of gamma irradiation on pasting characteristics and resistant starch levels of starches from locally-improved cassava accessions

摘要

The purpose of this study was to determine the effects of gamma irradiation on pasting characteristics and resistant starch (RS) levels of starches from some locally-improved cassava accessions. Three cassava accessions were collected from Ministry of Food and Agriculture-Root and Tuber Section at Pokuase, Accra, Ghana. Approximately, 10 kg of each accession was used for the starch extraction. Samples were irradiated at 0 (Control), 5, 10, 15 and 20 kGy. Pasting characteristics and RS levels of starch samples were evaluated. “Ankrah” recorded the highest RS levels (58.24 to 69.97%) amongst the three improved cassava starch accessions with TME 419 having the least RS content. Irradiation significantly (p 0.05) affected RS content, with the highest RS content obtained at 10 kGy absorbed dose. “Bosome Nsia” recorded the highest levels of non-resistant starch (NRS) content (47.56 to 63.16%) with values increasing gradually with increasing irradiation dose. Gamma irradiated modified “Ankrah” starch had the lowest gelatinization temperature, lowest maximum viscosity and highest setback and breakdown viscosities implying a good substitute to be used in food preparations.