An odor recorder for recording recipe of smell as well as reproducing it has been developed. It includes an array of sensors with partially overlapping specificities, odor blender and its recipe modification algorithm implemented in a computer. In the odor recorder, the recipe of the blended odor is iteratively modified so that the output pattern of the blended odor can agree with that of the target odor. The real-time reference method was developed to suppress the influence of the environmental change and to record the dynamical change of the odor. The target and blended odors are alternately supplied to the sensors and the recipe of the blended odor is adjusted so that the difference of the sensor responses between the two can be minimized. The dynamical change of the recipe of the four component odors in the apple flavor was successfully recorded without the influence of the environmental disturbance such as temperature and humidity changes.