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An array of ZnO thin film sensors was obtained by thermal oxidation of physical vapor deposited thin Zn films. Different conditions of the thermal treatment (duration and temperature) were applied in view of obtaining ZnO sensors with different gas sensing properties. Films having undergone a long thermal treatment exhibited high responses to low ethanol concentrations, while short thermal treatments generally led to sensors with high ethanol sensitivity. The sensor array was used to distinguish among Tequilas and Agave liquor. Linear discriminant analysis and the multilayer perceptron neural network reached 100% and 86.3% success rates in the discrimination between real Tequila and Agave liquor and in the identification of Tequila brands, respectively. These results are promising for the development of an inexpensive tool offering low complexity and cost of analysis for detecting fraud in spirits.

Casein is an abundant, cheap, and easy to modify milk protein, which is useful as a wall material to encapsulate organic and inorganic substances that can be applied to protect, load, and deliver flavorings, phenolic compounds, drugs, or inorganic substances. There are many reviews that have explored casein itself as well as the configuration of micelle structures to load substances, but there is a lack of condensed information about the physicochemical properties of casein capsules and the factors that influence them, such as the type of casein, core material and the methods used to obtain the capsules and characterize them. The aim of this review was to identify trends among the different types of casein proteins that can be used as wall materials for encapsulation, the type of core substances that are encapsulated, the reported size, the encapsulation efficiency, and the characterization methods. It can be assumed that each modification of the casein micelle such as the type of casein, active substance, the proportion of substance, and methods used to encapsulate can produce different results in terms of size, morphology and stabilization. These characterization plays a key role in understanding the physicochemical properties of casein encapsulates. In this review the factors that affect the encapsulation with casein as wall material and the characterization methods are presented.

A new biosurfactant was obtained from a moderately halophilic bacterium identified as Bacillus tequilensis ZSB10 that was isolated from a saline water pond located in Tehuacan‐Cuicatlan valley, Mexico. A kinetic analysis of the bacterial growth of the ZSB10 strain showed a maximum growth at 24 h regardless of the initial pH (5, 7.4, and 9). The best results were found at pH = 7.4 in terms of bacterial growth, besides which the produced biosurfactant showed emulsifying and surfactant properties with an emulsification index (E24) and surface tension change (ΔST) of 54 ± 0% and 26 mN m−1, respectively. Extracted ZSB10 crude biosurfactant had a yield of 106 ± 6 mg L−1, an E24 = 58.4 ± 0.2%, and a ΔST = 26 mN m−1 with a critical micelle concentration (CMC) of 44.82 mg L−1. Also, its structure was characterized by MALDI‐TOF mass spectrometry as a surfactin, iturin A, and fengycin mixture whose main isoform was leu/ile‐7 C15 surfactin [M + Na]+. Finally, the ZSB10 crude biosurfactant showed antifungal activity against Helminthosporium sp., with a 79.3% growth inhibition and an IC50 of 1.37 mg per disc. Therefore, this biosurfactant could be used as biopesticide.