Accuracy and application of milk fatty acid estimation with diffuse reflectance near-infrared spectroscopy

Abstract

Near infrared spectroscopy (NIRS) has the potential to estimate contents of fatty acids (FA) in milk frequently at-farm or during daily milking routine. In this study, a total of 738 raw milk spectra collected from 33 Holstein cows over a period of 30 weeks were recorded. Reference data on FA composition in milk and in milk fat were analysed in laboratory. Calibration models were calculated for single FA and groups of FA in milk and in milk fat. Validation resulted in sufficient Ratio of Prediction to Deviation (RPD) values for some single FA and in higher RPD values for groups of FA when concentrations of FA in milk were predicted. Since the concentrations of most FA in milk are highly correlated with milk fat content, the prediction of FA contents in milk fat is more meaningful when independent predictions are intended. The accuracy of predicting single FA concentrations in milk fat is rather poor for most FA but still comparable to alternative analysing methods such as MIR analysis. The estimation of different groups of FA in milk fat resulted in an improved accuracy based on higher RPD values, which was sufficient to mirror the development in the different lactation phases. The course of cow individual long chain fatty acid (LCFA) concentration in the early lactation stage can be an indicator for body fat mobilisation. The accurate estimation of the extent and duration of body fat mobilisation in cow individuals was rather difficult with NIR predicted LCFA concentrations and would require a higher measuring frequency than applied in this study.

Multifunctional Composites

“…Initially, the ratio between NiAu alloy and Ni:Au is 1:1, as in 2048 NiAu atoms, there are 1024 Ni atoms, 1024 Au atoms (NiAu 2048 ), 2916 atoms (NiAu 2916 ), 4000 atoms (NiAu 4000 ), 5324 atoms (NiAu 5324 ), 6912 atoms (NiAu 6912 ); all samples are studied by molecular dynamics (MD) simulation method [85][86][87][88][89][90][91][92][93][94][95] with embedded Sutton-Chen (SC) interaction [39,[96][97][98][99] and boundary conditions recirculating with the Equation (1):…”

“…Different approaches and measuring schemes (Figures 5 and 6) are used for the registration of the NIR spectra of milk, including collimated transmission (CT) [84], diffuse transmission (DT) [64], diffuse reflection (DR) [85], backscattering (BS) [86].…”

Milk as a Complex Multiphase Polydisperse System: Approaches for the Quantitative and Qualitative Analysis

“…Different approaches and measuring schemes (Figures 5 and 6) are used for the registration of the NIR spectra of milk, including collimated transmission (CT) [84], diffuse transmission (DT) [64], diffuse reflection (DR) [85], backscattering (BS) [86]. size distribution which can vary in each sample of milk [50].…”

“…Different approaches and measuring schemes (Figures 5 and 6) are used for the registration of the NIR spectra of milk, including collimated transmission (CT) [84], diffuse transmission (DT) [64], diffuse reflection (DR) [85], backscattering (BS) [86]. In contrast to the off-line milk analyzers based on FTIR spectrometers working in the MIR spectral region, NIR technology allows developing portable devices for fast on-farm milk quality control [95] and analytical solutions for in-line applications in milking robots [96] and automated milking systems [97].…”

Polymorphisms and genetic effects of PRLR, MOGAT1, MINPP1 and CHUK genes on milk fatty acid traits in Chinese Holstein

“…For dairy breeding, the weight of milk components has attracted more and more attention. Fatty acids (FAs) are the important components of milk fat, and the milk fat contains 70% of saturated fatty acids (SFAs) and 30% unsaturated fatty acids (UFAs) [1]. While, the ideal nutritional milk fat contain 10% polyunsaturated fatty acids, 82% monounsaturated fatty acids and 8% SFAs, that can not be accomplished by modifying diets of lactating cows [2].…”