Abstract:Hot air, infrared, infrared hot air and infrared spray drying techniques were used to dry fresh flowers with shell. The changes of peanut shell structure, nutritional components and energy consumption of peanut kernel during drying were investigated. The results showed that the dehydration rate of fresh peanut with shell was faster and the energy consumption was significantly reduced. Compared with hot air, infrared and infrared hot air drying, the dehydration time was shortened by 40%, 33% and 14%, and the energy consumption was reduced by 66%, 32% and 16% respectively. With the drying process going on, the reticular structure deformation of peanut shell and peanut kernel was obvious, and the porosity increased, and the maximum value was obtained under the infrared spouting condition. Under the four drying conditions, the hardness of peanut shell decreased at first and then increased, while the hardness of peanut kernel showed a trend of first increasing, then decreasing and then increasing; under the infrared spray drying mode, the decline rate of amino acid and fatty acid was 3.83% and 4.07% respectively compared with the fresh flowers without drying treatment, while the hot air drying, infrared drying and infrared hot air drying were not obvious. The degradation rates of amino acids and fatty acids were 9.53%, 7.77%, 9.06%, 9.27% and 5.83%, 4.97%, respectively. The experimental results showed that the infrared spouting drying was superior to the other three drying methods. It also provided theoretical support for the infrared spouting drying technology to be used in the drying of other shelled materials.