Study on the processing technology for purple potato granules

Purposes: This study aimed at developing production process of purple potato granules and improving the qualities of purple potato granules.Methods: The influences of factors on qualities of purple potato granules and the change of anthocyanidin during process were studied. The quality of production was also evaluated. Results:Drying temperature, drying time and comminution granularity were optimized through orthogonal experiments.Purple potatoes were processed through sorting and cleaning, peeling, color- protection, cooking and blanching, 10h drying under 60℃ and grinding to 60⁸0 mesh to get granules of high sensory quality and the yield rate was20.69%.The starch accounted for 54.50% and the protein was 7.30% in granules and the contents of polyphenol and anthocyanidin were 466.40mg /100g and 348.03mg /100g respectively.The cooking and drying processes were key processes which were most influential to the change of anthocyanidin.Conclusions: Purple potato granules of high quality can be obtained using the optimized process.Drying temperature and drying time should be carefully controlled to improve the quality of purple potato granules.