Nontargeted Analysis of Lipid Extracts Using ¹H NMR Spectroscopy Combined with Multivariate Statistical Analysis to Discriminate between the Animal Species of Raw and Processed Meat

Abstract

The animal species of raw meat and processed meat products was determined by 1 H NMR spectroscopy with subsequent multivariate data analysis. Sample preparation was based on comprehensive lipid extraction to capture nonpolar and polar (amphiphilic) fat components of meat. A nontargeted approach was used to analyze the 1 H NMR data, followed by a principal component analysis, linear discrimination analysis, and cross-validation embedded in a Monte Carlo re-sampling approach. A total of 437 raw meat samples (pork, beef, poultry, and lamb) and 81 processed meat samples (pork, beef, and poultry) were collected to build and/or test the classification model. On average, 98% of the analyzed raw meat samples and 97% of the processed meat products were correctly classified with respect to meat species. Furthermore, relevant spectral regions to identify potential chemical markers such as linoleic acids, trans-fatty acids, and cholesterol for the meat species classification were described.

1H NMR metabolic profiling for the differentiation of fish species

“…[17][18][19] High recognition rates have already been described for the differentiation of meat species. 20,21 We demonstrate the benefit of 1 H NMR spectroscopy for fish species discrimination using five different sample groups and prove the robustness of this method in the presence of typical additives such as citrate, even when their signals stay are included in the data analysis.…”

Differentiation of meat species of raw and processed meat based on polar metabolites using 1H NMR spectroscopy combined with multivariate data analysis

“…In a previously published paper, an attempt was made to build a classification model based on non-polar metabolites of meat (21). By combining data on polar and non-polar metabolites, a mid-level data fusion was used to establish a new classification model that contains maximum metabolite information.…”

“…The samples 1, 2, 3, and 4 were not assigned to any of the groups in the model that is based on non-polar metabolites. However, in these samples the composition of the two meat sources was more balanced than in sample 5 (21). By using the model that is based on polar metabolites, samples 1 and 2 were assigned within the 95% confidence interval of the beef group (Figure 8A).…”

“…In contrast, the accuracy for the pork based products was high, 98.4%, and acceptable for the poultry-based products, 93.3%, too. The model of the non-polar metabolites can be seen in previously published study (21). For the PCA/LDA, the scores of the first 14 dimensions of the PCA, which describe 99.4% of the variance in the data, were used.…”

“…In a previously published paper we were able to demonstrate that analysis of the non-polar metabolites of meat by 1 H NMR in combination with multivariate statistics allows for a differentiation of the meat species (21). Here, we combine a non-targeted 1 H NMR based analysis of polar meat metabolites with a multivariate statistical approach to differentiate between various meat species.…”