Due to their high water, lipid, and protein content, meat and meat products are highly perishable. The principal spoilage mechanisms involved are protein and lipid oxidation and deterioration caused by microbial growth. Therefore, efforts are ongoing to ensure food safety and increase shelf life. The development of low-cost, innovative, eco-friendly approaches, such as nanotechnology, using non-toxic, inexpensive, FDA-approved ingredients is reducing the incorporation of chemical additives while enhancing effectiveness and functionality. This review focuses on advances in the incorporation of natural additives that increase the shelf life of meat and meat products through the application of nanosystems. The main solvent-free preparation methods are reviewed, including those that involve mixing organic–inorganic or organic–organic compounds with such natural substances as essential oils and plant extracts. The performance of these additives is analyzed in terms of their antioxidant effect when applied directly to meat as edible coatings or marinades, and during manufacturing processes. The review concludes that nanotechnology represents an excellent option for the efficient design of new meat products with enhanced characteristics.

The release kinetics, stability, and antioxidant capacity of thyme essential oil polymeric nanocapsules as a function of encapsulating (poly-ε-caprolactone and ethylcellulose) and stabilizing (polyvinyl alcohol and Pluronic^® F-127) polymers were established. Samples were evaluated in terms of particle size, zeta potential, release kinetics, calorimetry, infrared spectra, antioxidant capacity, and diffuse reflectance. The particle size obtained was below 500 nm in all cases, ensuring nanometric size. Zeta potential as a function of the stabilizing polymer. Encapsulation efficiency was higher in the samples that contained ethyl cellulose (around 70%), associated with its affinity for the molecules contained in the essential oil. Differential scanning calorimetry revealed a strong dependence on the encapsulating polymers as a function of the melting temperatures obtained. Infrared spectra confirmed that the polymeric nanocapsules had the typical bands of the aromatic groups of thyme essential oil. The antioxidant capacity evaluated is a function exclusively of the active content in the nucleolus of the nanocapsules. Nanoencapsulation was not a significant factor. Diffuse reflectance revealed high physical stability of the dispersions related directly to the particle size and zeta potential obtained (either by ionic or steric effect). These findings confirm favorable characteristics that allow proposing these systems for potential applications in food processing and preservation.

Clenbuterol (Clb) can be present in Mexico often but not all over the world in animal tissues and organs, therefore, potentially is derived from animal sources as well. The aims of this study were to develop and validate a method for detecting traces of clenbuterol in beef sausages. A calibration curve showed linearity in the range of 20–500 pg ml⁻¹. The limit of detection (LOD) and lower limit of quantification (LLOQ) were 5 and 10 pg g⁻¹, respectively. The analyte recovery was from 95.70% to 100.40% with an intraday relative standard deviation (RSD%) of 0.99%–2.10% and an interday RSD% of 0.54%–2.34%, R² = 0.9998. The methodology developed was applied successfully in 15 samples of beef sausage, and 73.3% of the samples tested contained racemic clenbuterol in concentrations between 30 and 471 pg g⁻¹. The UHPLC–MS/MS method developed combines high sensitivity with good selectivity and short chromatographic run time. Additionally, the enantiomeric analysis of clenbuterol performed in beef sausages showed a 59% for R‐(−)‐Clb and 41% for S‐(+)‐Clb. The presence of clenbuterol in beef sausages could represent a risk of unintentional doping in sport field, because the clenbuterol is a banned substance included in the World Anti‐Doping Agency's (WADA) list of prohibited substances.

Several banned substances are illegally used by athletes in racemic mixtures for performance enhancement. These include clenbuterol, methyl hexaneamine, methamphetamines, and amphetamines. Clenbuterol is present in a large number of doping samples from Olympic and non‐Olympic athletes that have adverse analytical findings (AAFs). In some cases, the presence of these substances could be the result of consumption of meat contaminated with clenbuterol. In other cases, the origin is not clear. In this study, 27 products with racemic clenbuterol were evaluated using a new analytical methodology for the resolution of R‐(−) and S‐(+)‐enantiomers of clenbuterol by liquid chromatography–tandem mass spectrometry (LC–MS/MS) using a chiral column in 15 min with good separation. The method developed can also be used for the analysis of other biological matrices such as urine, serum, and meat. The resolution between two peaks' (R_s) value obtained using chromatographic data was 1.03. Both clenbuterol enantiomers were present in all products analyzed and the ratio was nearly 1. The origin of the product was not important for determining the presence of one or both enantiomers. All products displayed a 50:50 ratio of clenbuterol enantiomers. To the best of our knowledge, clenbuterol ratio determination of a large number of pharmaceutical preparations and black‐market products has not been reported previously. The information shown could be used by national anti‐doping organizations and the athletes with AAFs attributed to clenbuterol. Copyright © 2017 John Wiley & Sons, Ltd.