Reducing the oil absorption and tailoring starch properties in banana slices by integrated ultrasound in infrared frying

Abstract

The reduction of oil absorption and modifications of starch properties in infrared fried (IF) banana slices by integrated ultrasound was investigated with power levels ranged 600–1000 W. Results showed that the internal moisture migration in IF banana slices were enhanced by ultrasonication, the crust development was delayed and finally formed with a thinner layer and higher uniformity. Both the pore volume and the porosity of IF samples were reduced by the integrated ultrasound, while the accounts of pores with diameters 100–250 μm and 0.02–1 μm has been increased. The total oil uptake in IF samples was reduced by 1.5%–9.4% and both the surface and structural oil was decreased by the ultrasound. The order of starch in long range and short range in IF banana slices were reduced by the integrated ultrasound, while the formation of starch-lipid complex was increased, which leading to the prolonged starch digestion time.