Effect of processing on potato starch: In vitro availability and glycaemicindex

The content of digestible starch (DS) and resistant starch (RS) in processe d potatoes was assessed, In addition, the effect of domestic cooking on the in vitro digestibility of starch in this tuber, which may influence the gl ycaemic response, was studied. Resistant starch in raw potato is high, howe ver different RS values were obtained when processed, ranging from 1.18% in boiled potatoes to 10.38% in retrograded flour. In general, cooked potatoe s have high levels of DS. Starch digestibility is improved after processing and it is affected by the cooking methods. Boiled and mashed potatoes show ed the highest rate of digestion, on the contrary raw potato was hardly dig ested. The estimated Glycaemic Index (GI) from the degree of starch hydroly sis within 90 min was in accordance with the reported GI values, for potato es processed in the same way.