An amperometric enzyme electrode integrated with packed-bed column reactors containing immobilised enzymes was improved to measure glucose, sucrose and lactose content of food samples with only one sampling. Performance parameters of the system were investigated on the bases of linearity, sensitivity and response time. Those values were found to be 20 mM, 24.9 nA/mM and 20 s for glucose; 20 mM, 12.0 nA/mM and 3 min for sucrose; 12 mM, 10.8 nA/mM and 4 min for lactose, respectively. Overall analysis time for three analytes with one sampling was less than 8 min without pretreatment and interference of electroactive compounds and substrates. Glucose, sucrose and lactose content of the model and food samples were measured with both the improved system and commercial enzyme kits. There was high correlation between the results. This gives us the opportunity to use the improved electrode system for determination of glucose, sucrose and lactose in food samples. Also this result was found to be very promising in extending the spectrum of detectable analytes simply by addition of new columns containing immobilised enzymes that are specific to target analytes.