Edible foam based on Pickering effect of probiotic bacteria and milk proteins

Pickering emulsion stabilized by casein-caffeic acid covalent nanoparticles to enhance the bioavailability of curcumin in vitro and in vivo

BACKGROUND

In recent years, the design of food-grade Pickering emulsion delivery systems has become an effective strategy for improving the low bioavailability of bioactive substances. Protein-based Pickering emulsions have received extensive attention because of a high biocompatibility and loading capacity. The bioavailability of active substances is mainly evaluated by simulating in vitro gastrointestinal digestion. As a model organism for antioxidation and anti-aging, Caenorhabditis elegans can provide additional biological information for the in vivo utilization of active substances.

RESULTS

After the introduction of caffeic acid, the average particle size and Zeta potential of the casein-caffeic acid covalent complex nanoparticles (CCP) were 171.11 nm and - 37.73 mV, respectively. The three-phase contact angle was also increased to 89.8°. By using CCP to stabilize Pickering emulsion (CCE), the retention quantity of the embedded curcumin increased by 2.19-fold after 28 days. In the simulated gastric digestion, curcumin degradation in CCE was reduced by 61.84%, released slowly in the intestinal environment, and the final bioaccessibility was increased by 1.90-fold. In C. elegans, CCE significantly reduced ROS accumulation, increased SOD activity by 2.01-fold and CAT activity by 2.30-fold, decreased MDA content by 36.76%, prolonging the lifespan of nematodes by 13.33% under H₂ O₂ stimulation and improving bioavailability in vivo.

CONCLUSION

The results indictae that CCP-stabilized Pickering emulsion can efficiently implement the physiological activities of bioactive compounds in vitro digestion and C. elegans, and thus it can be regarded as a reliable delivery system for food and medicine. © 2023 Society of Chemical Industry.

Bacterial Cellulose Nanofibril-Based Pickering Emulsions: Recent Trends and Applications in the Food Industry

The Pickering emulsion stabilized by food-grade colloidal particles has developed rapidly in recent decades and attracts extensive attention for potential applications in the food industry. Bacterial cellulose nanofibrils (BCNFs), as green and sustainable colloidal nanoparticles derived from bacterial cellulose, have various advantages for Pickering emulsion stabilization and applications due to their unique properties, such as good amphiphilicity, a nanoscale fibrous network, a high aspect ratio, low toxicity, excellent biocompatibility, and sustainability. This review provides a comprehensive overview of the recent advances in the Pickering emulsion stabilized by BCNF particles, including the classification, preparation method, and physicochemical properties of diverse BCNF-based particles as Pickering stabilizers, as well as surface modifications with other substances to improve their emulsifying performance and functionality. Additionally, this paper highlights the stabilization mechanisms and provides potential food applications of BCNF-based Pickering emulsions, such as nutrient encapsulation and delivery, edible coatings and films, fat substitutes, etc. Furthermore, the safety issues and future challenges for the development and food-related applications of BCNFs-based Pickering emulsions are also outlined. This work will provide new insights and more ideas on the development and application of nanofibril-based Pickering emulsions for researchers.

Effect of Mixed Particulate Emulsifiers on Spray-Dried Avocado Oil-in-Water Pickering Emulsions

Avocado oil is a very valuable agro-industrial product which can be perishable in a short time if it is not stored in the right conditions. The encapsulation of the oils through the spray drying technique protects them from oxidation and facilitates their incorporation into different pharmaceutical products and food matrices; however, the selection of environmentally friendly emulsifiers is a great challenge. Four formulations of the following solid particles: Gum Arabic, HI-CAP^®100 starch, and phosphorylated waxy maize starch, were selected to prepare avocado oil Pickering emulsions. Two of the formulations have the same composition, but one of them was emulsified by rotor-stator homogenization. The rest of the emulsions were emulsified by combining rotor-stator plus ultrasound methods. The protective effect of mixed particle emulsifiers in avocado oil encapsulated by spray drying was based on the efficiency of encapsulation. The best results were achieved when avocado oil was emulsified with a mixture of phosphorylated starch/HI-CAP^®100, where it presented the highest encapsulation efficiency.

Application of Pickering emulsions in probiotic encapsulation- A review

Probiotics are live microorganisms that confer health benefits to host organisms when consumed in adequate amounts and are often incorporated into foods for human consumption. However, this has negative implications on their viability as large numbers of these beneficial bacteria are deactivated when subjected to harsh conditions during processing, storage, and passage through the gastrointestinal tract. To address these issues, numerous studies on encapsulation techniques to protect probiotics have been conducted. This review focuses on emulsion technology for probiotic encapsulation, with a special focus on Pickering emulsions. Pickering emulsions are stabilized by solid particles, which adsorb strongly onto the liquid-liquid interfaces to prevent aggregation. Pickering emulsions have demonstrated enhanced stability, high encapsulation efficiency, and cost-effectiveness compared to other encapsulation techniques. Additionally, Pickering emulsions are regarded as safe and biocompatible and utilize natural materials, such as cellulose and chitosan derived from plants, shellfish, and fungi, which may also be viewed as more acceptable in food systems than common synthetic and natural molecular surfactants. This article reviews the current status of Pickering emulsion use for probiotic delivery and explores the potential of this technique for application in other fields, such as livestock farming, pet food, and aquaculture.

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Probiotics play an important role in maintaining the health of humans and animals.

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Encapsulation improves probiotic viability in harsh environments.

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Probiotics can be encapsulated by many techniques such as emulsification.

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Pickering emulsions use particles instead of molecules to stabilize emulsions.

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Natural particles are more acceptable to some consumers than synthetic emulsifiers.

Shrinkage in frozen desserts

Shrinkage is a well-documented defect in frozen desserts, yet the root causes and mechanisms remain unknown. Characterized by the loss of volume during storage, shrinkage arose during the mid-twentieth century as production of frozen desserts grew to accommodate a larger market. Early research found that shrinkage was promoted by high protein, solids, and overrun, as well as postproduction factors such as fluctuations in external temperature and pressure. Rather than approaching shrinkage as a cause-and-effect defect as previous approaches have, we employ a physicochemical approach to characterize and understand shrinkage as collapse of the frozen foam caused by destabilization of the dispersed air phase. The interfacial composition and physical properties, as well as the kinetic stability of air cells within the frozen matrix ultimately affect product susceptibility to shrinkage. The mechanism of shrinkage remains unknown, as frozen desserts are highly complex, but is rooted in the physicochemical properties of the frozen foam. Functional ingredients and processing methods that optimize the formation and stabilization of the frozen foam are essential to preventing shrinkage in frozen desserts.

Efficient chemical hydrophobization of lactic acid bacteria - One-step formation of double emulsion

A novel concept of stabilizing multiple-phase food structure such as emulsion using solely the constitutional bacteria enables an all-natural food grade formulation and thus a clean label declaration. In this paper, we propose an efficient approach to hydrophobically modifying the surface of lactic acid bacteria Lactobacillus rhamnosus (LGG) using lauroyl ahloride (LC) in non-aqueous media. Compared to the unmodified bacteria, cell hydrophobicity was dramatically altered upon modification, according to the higher percentages of microbial adhesion to hexadecane (MATH) and water contact angles (WCA) of LC-modified bacteria. No evident changes were found in bacterial surface charge before and after LC modification. By using one-step homogenization, all the modified bacteria were able to generate stabile water-in-oil-in-water (W/O/W) double emulsions where bacteria were observed on oil-water interfaces of the primary and secondary droplets. Modification using high LC concentrations (10 and 20 w/w%) led to rapid autoaggregation of bacteria in aqueous solution. A long-term lethal effect of modification primarily came from lyophilization and no apparent impact was detected on the instantaneous culturability of modified bacteria.

The Concept of Microwave Foam Drying Under Vacuum: A Gentle Preservation Method for Sensitive Biological Material

Microwave vacuum drying as compared to conventional vacuum drying has evinced advantages regarding drying time, while comparable product characteristics were achieved when drying sensitive biological material. Due to the volumetric microwave input, a time reduction of up to 90% is possible. When drying viscous liquids, a foamed structure that remains stable during drying exhibits further advantages as the diffusion-limited third drying step is enhanced by the porous structure. As foams not only have to be thermally resistant during microwave vacuum processing, but also withstand the vacuum, a specific process for foam drying by microwaves under low pressure conditions was developed. Foam formation and stabilization was achieved by using a synergistic mixture of proteins and carbohydrates; Lactobacillus paracasei ssp. paracasei F19 (L. paracasei) served as a model sensitive substance. Investigation of surface activity and foaming properties as a function of L. paracasei concentration revealed a significant positive contribution of the bacterial cells. It was shown that L. paracasei directly adsorbed at the air-water interface. Besides, a structuring of the liquid lamellae was assumed. Moreover, drying time was reduced to at least 50% compared to microwave vacuum drying without foaming. It was further observed that the slight loss in survival was mainly due to the relatively high moisture content and high vacuum levels at the beginning of the process. However, foaming, vacuum application, and final drying, respectively, did not affect viability of the bacterial cells. Thus, by incorporation of lactic acid bacteria into foam structures, drying can be carried out in a fraction of time, and further results in high-product quality. PRACTICAL APPLICATION: The application of continuous foam drying offers an efficient and energy-saving alternative to the currently applied techniques for the processing of sensitive material. The process could be applied for the preservation of starter cultures and probiotics as well as in the pharmaceutical industry, when sensitive material such as therapeutic proteins is dried. This process is especially suitable for freezing-sensitive and thermolabile substances.