High‐intensity ultrasound is widely used to modify the functional properties of macromolecules (proteins, polysaccharides, etc.) and to expand their range of potential applications. This work is aimed at studying the effects of ultrasound treatments on the composition of different soybean okara samples and their potential as an emulsifying agent. Defatted solvent‐free soybean flour (DSF) was extracted by adjusting dispersion to pH 9.0. Insoluble residues obtained after centrifugation were dried, and an unsonicated okara sample (UOK) was obtained. Furthermore, the soybean flour dispersion was subjected to treatment in a probe‐type ultrasonic homogeniser before or after the alkaline extraction process, thus producing SOK and OKS samples, respectively. The sonication process generated compositional and structural changes in okara soybeans. SOK had higher yield and protein content than UOK and OKS due to the insolubilisation of the glycinin (11S) fraction of soybean storage proteins. Due to these characteristics, the SOK sample showed the best emulsifying activity.

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The production of soybean protein isolates generates an insoluble residue called okara that is rich in proteins and dietary fibre. These macromolecules have functional properties that can be modified and improved by emerging technologies, such as high-intensity ultrasound. The objectives of this work were to analyse the ability of soybean okara (UOK) to act as a gluten-free bread improver and to evaluate the effect of a sonication process on this property (OKS). Both okaras were assayed at two percentages (2% and 3%) leading to a reinforcement of interactions in the matrix of batters, producing bread of better technological and sensorial quality. The addition of OKS 3%, improved specific volume (20%), reduced the hardness (30%) and increased the cohesiveness of the crumb and improved the air inclusion. These results demonstrated the efficiency of the sonication process to obtain a gluten-free bread improver from a bulky by-product of the soybean industry.

The optimization of the process parameters was the aim of this study to obtain a powder from the pumpkin juice (Cucúrbita moschata) using the spray drying method. For the optimization of spray drying a surface response methodology was used, considering a central design composed of three factors: Maltodextrin concentration (10-25%), the temperature of the air inlet (150-170°C) and feed flow rate (4000-5000 mL/h) and the response variables evaluated to determine the optimal conditions of the process were: powder yield, humidity, hygroscopicity and solubility of the powder. The results of the statistical analysis indicate that all factors significantly affected the response variables, an increase in the addition of maltodextrin concentration to the pumpkin juice flow, generates an increase in yield, solubility and lower hygroscopicity values, the increase of the inlet temperature and the feed flow rate produced a decrease in the moisture content of the obtained powder. The optimal conditions of the process were reached with a 25% of maltodextrin concentration, 170°C for the air inlet and a flow rate of 4000 mL/h. These process parameters, allow obtaining a powder with a yield of 62.70%, humidity 3.40%, hygroscopicity 28.70% and solubility 71.5%, indicating a technological opportunity to generate and economic value to the pumpkin fruit, which allows improving the life quality of the country's farmers.