A Novel Method of Measuring Fat Content in Soybean Milk Based on Y-Type Optical Fiber Sensor

摘要

A new method of measuring fat content in soybean milk at room temperature (25℃) based on the Y-type optical fiber sensor is presented. The measurement system consists of a light source, Y-type optical fiber sensor, detector, thermoelectric cooler (TEC), preamplifier, second-level amplifier, A/D converter, and microprocessor. Based on the Mie theory, the diffuse reflection light intensity is adopted as the optical parameter representing the fat content in soybean milk. In this way the standard model of the system was established based on the diffuse reflection light intensity (the output voltage) of 40 soybean milk samples with different fat content. A prediction was also made to verify the measurement accuracy of the system (the prediction errors are within ±3 % of results). Results of this study indicate the feasibility of using this technology for soybean milk fat analysis that is suitable for the milk laboratory or field analysis.