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Complex coacervation between gelatin type B (GE) and chia mucilage (ChM) was studied. GE‐ChM were mixed at mass ratios of 1:1, 2:1, 3:1, 4:1, and 1:2 in a pH range of 1.50 to 5.00, maintaining a total solid concentration of 0.2% (w/w), using turbidity and viscosity tests to obtain the highest yield of complex coacervates. To characterize the complex coacervates, morphology and Fourier‐transform infrared spectroscopy (FTIR) were determined. The optimum yield for complex coacervation was achieved with a GE‐ChM mass ratio of 2:1 and pH value of 3.6. The critical pH values associated with the formation of soluble (pHc) and insoluble (pHɸ1) complexes, and complete dissociation (pHɸ2) at the optimum GE‐ChM ratio were found to be 4.50, 4.10, and 2.00, respectively. It was observed that increasing the mass ratio of GE or ChM, the yield of complex coacervates decreased; the higher yields were obtained with the proportions of 2:1 and 1:1 with values of 68.25 ± 0.05% and 61.04 ± 0.05%, respectively. Capsules formed at mass ratios of 1:1, 2:1, and 3:1, had the characteristic grape agglomerate shape for complex coacervates. Further characterization with scanning electron microscopy (SEM) showed a spherical shape for capsules. FTIR spectrum of complex coacervates at optimum conditions had a combination of bands corresponding to GE and ChM, suggesting an interaction between GE‐ChM during the formation of complex coacervates. Therefore, complex coacervates between GE‐ChM can be formed, and could be used as an alternative as encapsulating agents to be applied in the food industry. Practical Application Complex coacervation is a technique that is being studied in several applications in the food industry. However, studies are still being made to explore different possibilities of natural sources to be used in complex coacervation. This study showed that the combination of gelatin and chia mucilage may be an alternative as encapsulating agents for complex coacervation to be applied in the food industry.

Several in vitro studies of Mexican oregano essential oil (MOEO) have demonstrated its effectiveness as an antimicrobial. On the other hand, the encapsulation technique of emulsification could be used to mask the intense flavor of MOEO, protect it from physicochemical degradation, and release gradually its antimicrobial components. In the present study, emulsions were elaborated with two encapsulating agents, pectin or Arabic gum, with five concentrations of MOEO (0%, 5%, 7.5%, 10%, or 15% w/w). Emulsions were characterized by density, viscosity, particle size distribution, creaming index, and peroxide index. Emulsions were applied, in a 3:1 ratio, on the surface of two formulations of bagel, one with wheat flour (BW) and another with wheat flour and oats (BWO). Bagels were characterized by water activity, moisture content, and hardness. The antimicrobial activity of MOEO encapsulated by emulsification on Penicillium expansum on the surface of the bagels was determined. In addition, a sensory analysis of the bagels was carried out using a hedonic scale. All physicochemical properties of the emulsions had a significant difference (p < 0.05) because of the encapsulating agent used (pectin or Arabic gum). Emulsions stabilized with Arabic gum were more stable over time than the ones with pectin. The application of the emulsions on the surface of the bagels did not show a statistical difference (p > 0.05) in the physicochemical properties of the breads. The growth of P. expansum was delayed for up to 5 or 6 days in bagels with wheat flour and Arabic gum as encapsulating agent. Both systems, BW and BWO, atomized with MOEO emulsions at high concentrations (MOEO 15% w/w) were well accepted by the panel of judges when these were evaluated on day 0 (freshly baked bread) but not after 6 days of their elaboration.

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