María del Carmen Cortez-Trejo

Electrostatic protein–polysaccharide hydrogels are attractive materials formed without thermal denaturation or chemical crosslinkers and at low biopolymer contents. Their broader application in foods, however, has been limited by slow gelation, with network development often requiring many hours (~18 h). In this study, millimeter-scale hydrogel beads were fabricated from amaranth proteins and xanthan gum by extrusion into glucono-δ-lactone (GDL) solutions (1–5 mg/mL) using hardening times of 10 or 30 min. Beads were successfully formed under all conditions (3.07–3.95 mm diameter), and their physicochemical properties, intermolecular interactions, microstructure, and gel strength were evaluated. Electrostatic attraction remained the dominant force driving gelation. Furthermore, 10 min hardening favored interpolymeric electrostatic interactions, whereas longer exposure reduced them and promoted hydrogen bonding and hydrophobic interactions. These molecular rearrangements were accompanied by a decreased size, lower water retention capacity (WRC), and higher mechanical strength. The mildest treatment (1 mg/mL GDL, 10 min) was post-loaded with a coffee pulp phenolic extract and showed reduced gel strength and electrostatic interactions, suggesting competition for binding sites within the macromolecular network. The extrusion of amaranth protein–xanthan gum mixtures into a GDL bath markedly shortens electrostatic gelation time, supporting this approach as a potential alternative to ionic gelation for the production of millimeter-scale hydrogel beads for food applications.

Buttermilk, a by‐product of butter manufacturing, is rich in proteins and milk fat globule membrane (MFGM) components with valuable techno‐functional properties; however, it remains underutilized in the dairy industry. This study investigated the impact of high‐intensity ultrasound (HIUS, 20 kHz) on the structural and functional properties of buttermilk and evaluated its application in ice cream formulation. Buttermilk solutions were subjected to HIUS at different amplitudes (20%, 40%, and 60%) and durations (5, 10, and 15 min). Protein structural changes were characterized by free sulfhydryl content and Fourier transform infrared (FTIR), while functional properties, including solubility, viscosity, fat absorption capacity (FAC), and emulsifying indices, were assessed. Moderate HIUS treatments (20‐5, 20‐10, 20‐15, and 40‐5) significantly increased thiol exposure ( p < 0.05), whereas more intense conditions appear to promote protein association. However, most functional properties showed no significant differences with the control; the only exception was FAC, which showed significant improvement in almost all cases ( p < 0.05). Accordingly, FTIR spectra confirmed rearrangements in protein secondary structure and enhanced protein–lipid and protein–lactose interactions. Compared to the control and a sample with nonsonicated buttermilk, the ice cream with HIUS‐treated buttermilk (20% amplitude for 5 min) exhibited lower overrun (~8%) and improved meltdown resistance, attributed to its denser and compact microstructure by confocal microscopy. Sensory evaluations showed that all three ice cream formulations received favorable ratings and no significant differences among them, on the 9‐point hedonic and labeled affective magnitude (LAM) scales. However, the HIUS‐treated buttermilk ice cream showed slightly lower scores, mainly for texture and overall liking, which may be associated with ultrasound‐induced changes and reduced air stabilization capacity. Overall, under the conditions studied, HIUS treatment enhances specific functionalities of buttermilk and demonstrates potential for improving frozen dairy products. Optimization of ultrasound parameters and HIUS‐treated buttermilk doses is recommended to maximize functional benefits while minimizing negative effects on product quality and consumer acceptance.

Probiotics offer significant health benefits; however, their efficacy is often compromised by low survival rates in stressful conditions. Microencapsulation using modified starches presents a promising strategy to enhance probiotic viability. This study aimed to evaluate microwave-assisted octenyl succinic anhydride (OSA) modification of faba bean starch to provide a protective matrix for the microencapsulation of Lactobacillus rhamnosus GG (LGG) through spray drying. Starch was extracted from faba beans and hydrolyzed, and a factorial design was employed for OSA esterification (3% w/w) using a conventional microwave (30 or 60 s at power levels of 2 or 10). The starches were characterized, and the most effective treatment was selected for the microencapsulation of LGG, varying the inlet temperature (120 and 140 °C) and flow rate (7 and 12 mL/min) at 30% solids content. Microwaves significantly reduced the processing time for starch esterification. Microwave-assisted OSA modification produced starches with low viscosity (<0.015 Pa·s), high amylose and resistant starch content, and good solubility, making them suitable for probiotic encapsulation. The microencapsulation of LGG resulted in a powder yield of 41–55%, with particle sizes ranging from 5 to 20 µm and survival rates of 81–90%. This study presents an effective method of producing OSA-modified starch from faba beans using microwave energy, demonstrating strong potential for probiotic delivery applications.

Traditional Mexican non-alcoholic, cocoa-based beverages are a relevant part of the gastronomy of the country. This study aimed to identify the volatile compound profile of three traditional beverages from Mexican gastronomy, including Pozol, Chilate, and Cacahuatole, and evaluate the acceptability of milks incorporating their traditional flavors. Chemical composition was determined, and volatile compounds were analyzed using gas chromatography–mass spectrometry (GC-MS). The results showed the Mexican beverages are rich in carbohydrates (70.3–78.2% d.b.), proteins (9.3–16% d.b.), and fat (8.8–11.7% d.b.) due to corn, rice, broad beans, and cocoa ingredients. GC revealed volatile profiles, with Pozol containing 148, Chilate 104, and Cacahuatole 109 compounds, mainly terpenes, pyrazines, aldehydes, and phenolics. Nixtamalization, cocoa roasting, and ingredient variations influenced the volatile composition and sensory attributes. Multivariate analysis distinguished the beverages based on their volatile composition, revealing ingredient-dependent variations. Artificial flavors replicating these profiles were developed and incorporated into milks, which were evaluated by a trained sensory panel using the Check-All-That-Apply (CATA) method. Sensory analysis confirmed that key aromatic compounds contributed to flavor perception. This work identified for the first time the volatile compounds of traditional Mexican cocoa-based beverages, namely, Pozol, Chilate, and Cacahuatole, and provides insight into the role of traditional preparation methods in the development of flavor profiles. On the other hand, this study highlights the potential for incorporating traditional Mexican beverage flavors into commercial milk for novel product development.