Recently, the interest of consumers regarding artisan cheeses worldwide has increased. The ability of different autochthonous and characterized lactic acid bacteria (LAB) to produce aromas and the identification of the volatile organic compounds (VOCs) responsible for flavor in cheeses are important aspects to consider when selecting strains with optimal aromatic properties, resulting in the diversification of cheese products. The objective of this work is to determine the relationship between VOCs and microorganisms isolated (Lacticaseibacillus paracasei, Lactiplantibacillus plantarum, Leuconostoc mesenteroides and Lactococcus lactis subsp. hordniae) from raw sheep milk cheeses (matured and creamy natural) using accuracy and alternative methods. On combining Sanger sequencing for LAB identification with Gas Chromatography coupled to Ion Mobility Spectrometry (GC–IMS) to determinate VOCs, we describe cheeses and differentiate the potential role of each microorganism in their volatilome. The contribution of each LAB can be described according to their different VOC profile. Differences between LAB behavior in each cheese are shown, especially between LAB involved in creamy cheeses. Only L. lactis subsp. hordniae and L. mesenteroides show the same VOC profile in de Man Rogosa and Sharpe (MRS) cultures, but for different cheeses, and show two differences in VOC production in skim milk cultures. The occurrence of Lactococcus lactis subsp. hordniae from cheese is reported for first time.

The global emission and accumulation of gases due to livestock farming is estimated to contribute to about 14.5% of the global warming effect due to greenhouse gases (GHG). Pig farming represents 9% of global livestock GHG emissions, without considering other activities of pork production process, such as feed production. Most of information about pig farms GHG emissions is based on theoretical calculations with not too much accuracy. Hence, there is a critical need to study the best sampling and analytical techniques (portable or not) that can be used to map their contribution to GHG emissions. The selection of the best analytical detection method becomes important for public policies on climate change, and in order to evaluate animal and manure handling practices to reduce GHG and to combat global warming. In this article, different techniques, which could be used to measure the emissions of GHG from livestock, are reviewed, showing the advantages and disadvantages of each technique, with special emphasis on those already used in studies about GHG from pig farms and those that allow the simultaneous determination of several species of gases. Open chambers equipped with photoacoustic multi-gas monitor have been the techniques most employed in intensive pig farms studies. Gas Chromatography coupled to different detectors has been only widely used in pig farms to monitor simultaneously several GHG species using previous sampling devices. However, there are no studies in the literature based on extensive pig farms. In these systems, micrometeorological techniques could be a promising strategy.

Disinfected water and/or disinfectants are commonly used by the freezing industry in such processes as sanitising, washing, blanching, cooling and transporting the final product. For this reason, disinfection by-products (DBPs) can be expected in frozen foods. This study focused on the presence of DBPs in a wide variety of frozen vegetables, meats and fish. For this purpose, the 14 halogenated DBPs more prevalent in disinfected water were selected (four trihalomethanes, seven haloacetic acids, two haloacetonitriles and trichloronitromethane). Up to seven DBPs were found in vegetables, whereas only four DBPs were present in meats and fish, and at lower concentrations, since their contact with disinfected water is lower than in frozen vegetables. It is important to emphasise that trichloronitromethane (the most abundant nitrogenous DBP in disinfected water) was found for the first time in foods. Finally, it was concluded that the freezing process can keep the compounds stable longer than other preservation processes (viz. sanitising, canning) and, therefore, frozen foods present higher DBP concentrations than other food categories (minimally processed vegetables, or canned vegetables and meats).