Discrimination of spoiled beef and salmon stored under different atmospheres by an optoelectronic nose. Comparison with GC-MS measurements

Abstract

The aim of this study was to evaluate the capacity of an electronic nose, the NeOse Pro, to assess the alteration of two food matrixes of animal origin, beef and salmon. For each matrix, two types of samples were analyzed, natural samples and simplified “diluted” samples based on meat juice and agar. Samples were inoculated with specific spoilage organisms and stored for 6 days at 8°C under different conditions: air, modified atmosphere packaging, and vacuum packaging. A non-inoculated control sample was stored at -80°C under vacuum packaging. Results of the NeOse Pro were compared with gas chromatography coupled to mass spectrophotometry analysis. For this purpose, heatmaps, principal component analysis and discriminant analysis were used. GC-MS results show that the major detected volatile organic compounds for beef stored under air are dimethyl disulfide and ethyl acetate. For salmon stored under air, it was mainly dimethyl disulfide, methyl thioacetate, acetoin and ethyl acetate that were produced. For beef and salmon NeOse Pro and GC-MS results are consistent; samples stored under air are separated from other samples.