Textural Properties and Sensory Quality of Processed Sweetpotatoes as Affected by Low Temperature Blanching

Sweetpotatoes (SP) stored for 9-12 mo after harvest were cut into cylindrical pieces and, following factorial experiments and response surface design, were blanched at 50-80°C for 15-274 min. Instrumental textural properties were measured by uniaxial compression and texture profile analysis. Samples of selected blanching treatments were canned in syrup for textural and sensory evaluations. Both blanching temperature and time had significant effects on firmness. Optimal temperature for maximal firmness retention was about 62°C. For canned SP, the 62°C blanched samples were more intact (2-3-fold) and firmer (2-7-fold) than controls. Sensory texture and overall acceptability were greatest for samples blanched at 62°C for 30 or 45 min before canning.