_applied_  
_sciences_  
_Editorial_  
Analysis of Chemical Biomarkers and Contaminants in Food  
**[PERSON] \({}^{\star}\)\({}^{\copyright}\) and [PERSON] \({}^{\star}\)\({}^{\copyright}\)**  
Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52,  
10126 Torino, Italy  
\({}^{\star}\) Correspondence: [EMAIL_ADDRESS] (F.D.B. ); [EMAIL_ADDRESS] (C.M.) The quality of food has become of great importance and relevance in recent years, not only for scientific communities but also for ordinary people. Many research papers are centered around the issue of quality control with regard to the presence of contaminants in foods. Additionally, the recognition of a biomarker, intended as a biological characteristic measured and evaluated as an indicator of biological processes (normal, pathogenic, or pharmacological), plays a key role in quality control. Chemical biomarkers present in food are molecular entities of different origins. They may be present in the animal or vegetal material, exogenously, endogenously or endogenously transformed by metabolism from exogenous sources. Exogenous biomarkers can coincide with contaminants. The identification and measurement of contaminants and biomarkers are achievable with food chemical analysis based on many analytical methods, from immunoassay detection to mass spectrometry evaluation. The qualitative and, above all, quantitative chemical methods applied to food matrices are useful for determining the threshold of contaminants that could have an adverse effect on public health. Here, we propose a Special Issue of _Applied Sciences_ to present a limited but remarkable number of researches regarding the identification and quantitation of contaminants and biomarkers in food. The main technique used is mass spectrometry (MS), coupled with gas or liquid chromatography (GC or LC), respectively. This technology allows one to quantify even traces of targeted analytes and to identify and characterize untargeted molecules. Many chemical compounds could be analyzed with mass spectrometry, from volatile substances (GC-MS) to proteins (LC-MS), or from heterocyclic and organic aromatic contaminants to highly polar substances. Five out of six research papers presented in the Special Issue achieved their goals using MS, even high-resolution MS. However, MS is not the only suitable technique to perform analysis on food contaminants and biomarkers. Immunoassay-based devices take up a large part of food analysis, reaching very low limits of detection and quantitation. Several food matrices were analyzed during the studies presented in this issue: hazelnuts, meats, milk (bovine and human), and water. Summarily, this Special Issue includes six high quality research papers concerning:  
* The study of the metabolome of raw and roasted hazelnuts harvested in Italy (Piedmont) and Georgia [1]. The comparison was achieved applied an innovative analytical method based on two-dimensional gas chromatography coupled with fast-scanning quadrupole mass spectrometry (GC\(\times\)GC-qMS) in untargeted and targeted approaches. The data acquired were compared statistically with principal component analysis that highlighted the variations in the metabolome of raw and roasted hazelnuts. The validation of an analytical HPLC-UV-MS method applied to food and biological matrices for the quantitation of 16 phytoestrogens [2]. These molecules are plant metabolites and their consumption was associated with a lower probability of developing cancer or cardiovascular diseases. The method was successfully applied to highly consumed food items from North Mexico and biofluids from healthy women. The development of a new immunoassay device based on lateral flow for the detection of myoglobin as a specific biomarker of porcine muscle tissue [3]. The developedtechnology showed a very low limit of detection of 5 ng/mL, and the applications of the method concerned the possibility of controlling the quality of the meat products.