用于乳品新鲜度快速识别的纸基渗流芯片设计与响应

目的 开发一种灵敏、快速、便捷的用于原位实时识别液态乳品新鲜度的装置和方法。方法 以超高温瞬时灭菌乳为研究对象,采用氧化铟锡（Indium Tin Oxide, ITO）导电玻璃作为装置的传感电极材料,在具有毛细管力的纸基上设计渗流通道,制备纸基渗流芯片并搭建检测装置,利用制备好的纸基渗流芯片和装置开展乳品腐败全过程的介电性能研究;同时利用pH复合电极测量乳品腐败过程的pH值。结果 在乳品腐败全过程（开封储存50 h）中,pH对乳品的质量变化不够敏感,而制备出纸基渗流芯片和检测装置能够快速测定液态乳品介电参数的微小变化,测得的介电常数随着乳品质量变化呈现3个“V”形状的波动变化,更能反映出乳品的质量变化。结论 该装置和方法可以用于开封后液态乳品质量状态的实时测定,为消费者判断液态奶的食用质量提供参考。

Design and response of paper-based seepage chip for quick identification of dairy freshness

Objective To develop a sensitive, fast and convenient device and method for real-time identification of liquid milk freshness in situ. Methods Taking ultra-high temperature instantaneously sterilized milk as the research object, ITO was used as the sensing electrode material of the device. The percolation channel was designed on the paper base with capillary force, and the paper base percolation chip was prepared and the detection device was built. The dielectric properties of the whole process of milk corruption were studied by using the prepared paper base percolation chip and device. At the same time, the pH value of milk was measured by pH composite electrode. Results In the whole process of dairy corruption (Store for 50 h after opening), pH was not sensitive to the change of milk quality. However, the paper-based percolation chip and the detection device were prepared to quickly measure the small changes of the dielectric parameters of liquid milk, and the measured dielectric constant showed three "V" shape fluctuations with the change of the quality of milk, reflecting the quality change of milk. Conclusion The device and method can be used for the real-time determination of the quality status of liquid milk products after opening, providing a reference for consumers to judge the edible quality of liquid milk.