Taste can be measured using a taste sensor, which shows different electrical potential patterns for each food. The sensor has eight kinds of lipid membranes. The present study is concerned with the long-term measurements of milk and sensory analysis of milk. Each membrane was preserved in standard milk, and the tastes of five kinds of commercial milk were measured using the sensor preserved for a period of one month to six months in the same manner. It was found that calibrated data was comparable with data obtained other days, and that the membranes were used reliably for six months. On the other hand, richness of sensory test showed a high correlation with the ratio of milk fat using chemical analysis, as seen from the correlation coefficient 0.829. It was also found that there is significant difference among the four samples by performing a Kramer test (α < 0.01) and F test (α < 0.05). We used multiple regression analysis on sensor responses by use of the ratio of milk fat and the heat treatment of milk, and consequently found a high correlation between channel 4 and them. The correlation coefficient was-0.986 between the sensory test and ch. 4. Therefore, it was concluded that richness, which is the main taste of milk, can be quantified using the taste sensor. © 2000, The Institute of Electrical Engineers of Japan. All rights reserved.