Mass spectrometry based proteomics as foodomics tool in research and assurance of food quality and safety

Peptide Selection for Accurate Targeted Protein Quantification via a Dimethylation High-Resolution Mass Spectrum Strategy with a Peptide Release Kinetic Model

“…where a equaled A, k equaled (1 + K M /A), and m equaled v max / A. For the fitting of digestion curves, the production of fully tryptic peptides from the BSA standard with and without raw milk matrix at different digestion times (2,4,6,8,10,20,40,60,80, 100, and 120 min) was determined by high-resolution mass spectrum in full MS mode and quantified by the light-toheavy isotope ratio, in which the heavy isotopic label was the heavy-labeled peptide solution of BSA standard with 120 min of digestion time. On the basis of eq 3, the digestion curves were fitted using PROC NLIN in SAS (version 9.4) and the iterative method was Gauss−Newton ( Figure S1).…”

Sample preparation in foodomic analyses

“…A sample stabilization system that uses heat for a reproducible and fast step for enzyme inactivation was introduced . However, its use for food samples is questionable, since thermal treatment can result in irreversible changes of food components and their physical and chemical properties as a consequence of possible undesirable reactions (such as Maillard reaction and other nonenzymatic changes, ) and it can further influence analytical results. Like in other “omics” strategies, standardized and validated sample handling and sample preparation protocols have to be defined, in order to enable correct data interpretation .…”

“…Like in other “omics” strategies, standardized and validated sample handling and sample preparation protocols have to be defined, in order to enable correct data interpretation . Through routinely performed checks and balances, the specialist for the MS‐based food proteomics is the key person who ensures the high fidelity of the used analytical platform . For this sake, routine use of a defined standard was recommended for control of both the purification efficiency and the efficiency of protease digestion , but the lack of standardized and validated methods is still a severe problem for the use of all “omics” strategies, and it includes the proteomics ones .…”

“…As a negative consequence of these facts, most frequently quantitative, but sometimes also qualitative information, will be compromised. Food matrix components, different additives, and food treatment during storage and processing can significantly influence protein and peptide stability and solubility, protease digestion, and treatment with other enzymes (such as glycosydases), as well as peptide detection and analysis of PTMs and other modifications during food processing in further MS or MS/MS steps (or other methods of proteomic analyses, see ). Cell sorting techniques or techniques for isolation of individual cell types from complex tissues are available, but they are not frequently used in food analyses (“for a good reason,” according to authors).…”

“…Cell sorting techniques or techniques for isolation of individual cell types from complex tissues are available, but they are not frequently used in food analyses (“for a good reason,” according to authors). Among them are laser capture microdissection, fluorescence‐activated cell sorting, gradient centrifugation, and free‐flow electrophoresis , but these methods are practically not applicable for processed food. Sample amount is usually not a problem in food analysis; however, quantification is especially vulnerable due to the possible interference of different food matrix compounds, additives, and the effects of food processing procedures.…”