Qualitative Analysis of Dairy and Powder Milk Using Laser-Induced Breakdown Spectroscopy (LIBS)

Abstract

Laser-induced breakdown spectroscopy (LIBS) technique was used to compare various types of commercial milk products. Laser-induced breakdown spectroscopy spectra were investigated for the determination of the elemental composition of soy and rice milk powder, dairy milk, and lactose-free dairy milk. The analysis was performed using radiative transitions. Atomic emissions from Ca, K, Na, and Mg lines observed in LIBS spectra of dairy milk were compared. In addition, proteins and fat level in milks can be determined using molecular emissions such as CN bands. Ca concentrations were calculated to be 2.165 ± 0.203 g/L in 1% of dairy milk fat samples and 2.809 ± 0.172 g/L in 2% of dairy milk fat samples using the standard addition method (SAM) with LIBS spectra. Univariate and multivariate statistical analysis methods showed that the contents of major mineral elements were higher in lactose-free dairy milk than those in dairy milk. The principal component analysis (PCA) method was used to discriminate four milk samples depending on their mineral elements concentration. In addition, proteins and fat level in dairy milks were determined using molecular emissions such as CN band. We applied partial least squares regression (PLSR) and simple linear regression (SLR) models to predict levels of milk fat in dairy milk samples. The PLSR model was successfully used to predict levels of milk fat in dairy milk sample with the relative accuracy (RA%) less than 6.62% using CN (0,0) band.

Qualitative and semi-quantitative analysis of health-care pharmaceutical products using laser-induced breakdown spectroscopy

“…The resulting spectral lines are recorded by this instrument, which is typically connected to a PC. When a typical measurement is performed, the observed spectral lines are compared with those in the database of the National Institute of Standards and Technology (NIST) to facilitate the identification of the elements [4], [5]. LIBS is widely applied in numerous areas including process monitoring due to its rapidity, ability to perform noncontact optical measurement, minimal sample preparation requirement, and potential to perform real-time in-situ measurements for laboratory or industrial use.…”

Signal Enhancement Evaluation of Laser-Induced Breakdown Spectroscopy of Extracted Animal Fats Using Principal Component Analysis Approach

“…successfully able to separate different types of milks in the score plot by applying PCA method on the obtained LIBS emission signals. 22…”

“…20 For instance, PCA has been applied to discriminate the similar LIBS spectra of various types of pig head tissues which are fat, muscle, nerve, and skin into four clusters in the score plot, 21 while Alfarraj et al successfully able to separate different types of milks in the score plot by applying PCA method on the obtained LIBS emission signals. 22 Since LIBS on liquid sample produced weak signals, 17 this study aims to improve the LIBS emission signals of extracted animal fats which in liquid formed by transformed into solid phase using freezing methods. Here, the samples consisted of the extracted chicken fat, lamb fat, beef fat, and lard frozen using freezer and LN 2 methods.…”

Detection of Pistacia vera adulteration by using laser induced breakdown spectroscopy

“…In this way, LIBS provides multi‐elemental analysis of samples at the same time as requiring minimal/no sample preparation. There are several LIBS applications in food analysis . The focus of the present study is to evaluate the potential of LIBS combined with chemometric data analysis, namely principal component analysis (PCA) and partial least squares (PLS), as a rapid method for determining pistachio adulteration with spinach and green pea.…”