Tvorba a zánik komplexních molekulárních iontů v plynné fázi

Katedra fyziky povrchů a plazmatuDepartment of Surface and Plasma ScienceFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

Real Time Detection of Aroma Compounds in Meat and Meat Products by SIFT-MS and Comparison to Conventional Techniques (SPME-GC-MS)

The applicability of selected ion flow tube mass spectrometry, SIFT-MS, for the study of the quality of meat and meat products in comparison to conventional techniques (SPME-GC-MS) has been investigated. To this end, two different approaches were followed. The first was to study the release of aroma compounds after saliva addition to fermented sausages and the second, the application of SIFT-MS and SPME-GC-MS to the detection of chemical spoilage in retail meat (raw and cooked). The headspace (HS) concentration of volatile compounds was influenced by saliva addition to the fermented sausage. SIFT-MS obtained better correlations than SPME-GC-MS between compound release and their molecular weight, MW, and hydrophobicity properties. Saliva differentially affected the release of the compounds, suppressing the release of hydrophilic and low MW compounds and either having little effect or enhancing the release of hydrophobic and higher MW compounds. These results provide preliminary explanations of aroma perception during eating. In addition, SIFT-MS was able to detect differences in the same way as SPME-GC-MS in fresh beef meat during refrigerated storage, but the differences were hardly detectable in cooked meat. Therefore, SIFT-MS can be used as a fast monitor of lipid oxidation changes in retail meat packaged in high oxygen atmospheres.Financial support from MINECO (Spain) and Academy of Science of the Czech Republic for the joint project (project number 2010CZ0011) are fully acknowledged. Partial funding from AGL 2009-08787 from MINECO (Spain), PROMETEO 2012-001 (GVA, Spain) and FEDER funds and by Grant Agency of the Czech Republic (projects number 203/09/P172 and 203/09/0256) are also gratefully acknowledged.Peer Reviewe

Rapid detection of lipid oxidation in beef muscle packed under modified atmosphere by measuring volatile organic compounds using SIFT-MS

8 pages, 4 tables, 2 figures.-- Available online 29 June 2012The objective of this work was to evaluate the use of a direct analysis technique (SIFT-MS) to measure the lipid oxidation process in beef meat packed under high oxygen atmosphere and compare it to conventional techniques such as gas chromatography–mass spectrometry analysis and TBARS values. Meat samples from two suppliers were selected and packaged under the same atmosphere conditions. The fatty acid content, the physicochemical (TBARS and volatile compounds) and sensory parameters were measured. The samples from supplier 2 had a highest content of PUFA and n6 fatty acids that was related with a highest oxidation during storage. SIFT-MS and SPME-GC–MS detected a significant increase for most of the volatiles compounds analyzed during storage especially, in aldehyde compounds. High correlation coefficients between TBARS values and linear aldehydes (C3–C7) measured by both techniques were obtained and this indicates that SIFT-MS can be used to monitor lipid oxidation changes.Financial support from MINECO (Spain) and Academy of Science of the Czech Republic for the joint project (project number 2010CZ0011) are fully acknowledged. Partial funding from AGL 2009-08787 from MINECO (Spain), Prometeo 2012-001 (GVA) and FEDER funds and by Grant Agency of the Czech Republic (projects number 203/09/P172 and 203/09/0256) are also gratefully acknowledged.Peer reviewe