[Analysis and discrimination of infant powdered milk via FTIR spectroscopy]

Yue-e Deng1, Qun Zhou, Su-qin Sun

  • 1Department of Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, China.

Six kinds of infant powdered milk were identified by Fourier transform infrared spectra (FTIR) and their corresponding second derivative infrared spectra. The main nutritious components such as lipid (1,747, 2,854 and 2,926 cm(-1)), protein (1,658 and 1,540 cm(-1)), and carbohydrate(1,200-900 cm(-1)) of had distinct fingerprint characteristics of FTIR spectra. Maltodextrin, sucrose and lactose also had obvious spectral characteristics, which changed with different added content. For the samples from the same factory but with different sorts, there was some dissimilarity in the relative intensities of infrared absorption peaks due to the difference in fat, protein and carbohydrate. For the samples of the same sort but from different factories, there are certain similarities in the IR spectra, however, the second derivative infrared spectra present different fingerprint characteristics. This analytical method is fast and direct for evaluating the quality of infant powdered milk.

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