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Title Determination of hypochlorite in milk using a portable photometer
Type Presentation
Keywords Paired emitter-detector diode-based photometer, Miniaturization, Milk adulteration, Liquid bleach adulteration, Point-of-use testing.
Abstract The short shelf life of Milk has always been a problem. Some small business milk producers utilize various adulterations to increase the shelf life, potentially risking the health of end-users [1]. These adulterations may include the addition of hypochlorite [2]. As a result of the bleach solution's contact with the milk components, chemical reactions occur [3]. The determination of bleach solution adulteration in milk by the present methods in Iran were not applicable for this aim due to the fast reaction of ClO - anions with milk compounds and the low residual concentration of it in the milk received by the end-users. Then, the determination of bleach adulteration in milk is by a developed method critically important. Paired emitter- detector diodes (PEDD) based on photometers provide low fabrication cost, low power consumption, ease of miniaturization and a high signal-noise ratio response in a large wavelength range [4]. This paper reports on developing a cheap but efficient paired emitter- detector diode (PEDD)-based photometer. The photometer consists of a white light-emitting diode (LED) as the emitter diode, an RGB LED as the detector diode and a multimeter for recoding the signal. The developed PEDD-based photometer was used for the determination of liquid bleach adulteration in cow milk samples. N, N-Diethyl-p-phenylenediamine sulfate aqueous solution (pH=6.0) was used as a probe to monitor the presence of residual active chlorine in milk. Finally, the calibration curve for determining sodium hypochlorite by using the developed method covered a linear dynamic range, 0.5 to 20.0 ppm, with a detection limit of 0.14 ppm and quantification limit of 0.46 ppm. Real sample analysis results showed that some pasteurized milk products.
Researchers Mohsen Majidi (Not In First Six Researchers), (Fifth Researcher), Abbas Afkhami (Fourth Researcher), Tayyebeh Madrakian (Third Researcher), Mazaher Ahmadi (Second Researcher), . . (First Researcher)