Current Advantages in the Application of Microencapsulation in Functional Bread Development

Bread is one of the most widely embraced food products and is highly accepted by consumers. Despite being rich in complex carbohydrates (i.e., starch), bread is generally poor in other micro- and macronutrients. Rising consumer demand for healthier food has resulted in the growth of studies focused on bread fortification with bioactive ingredients (i.e., vitamins, prebiotics, and vegetable extracts). However, the baking process leads to the reduction (or even lessening) of the added substance. In addition, the direct inclusion of bioactive compounds and additives in bread has other limitations, such as adverse effects on sensory characteristics and undesirable interaction with other food ingredients. Encapsulation allows for overcoming these drawbacks and at the same time improves the overall quality and shelf-life of bread by controlling the release, protection, and uniform distribution of these compounds. In the last ten years, several studies have shown that including micro/nano-encapsulated bioactive substances instead of free compounds allows for the enrichment or fortification of bread, which can be achieved without negatively impacting its physicochemical and textural properties. This review aims to identify and highlight useful applications in the production of new functional bread through encapsulation technology, summarizing the heath benefit and the effect of microcapsule inclusion in dough and bread from a technological and sensory point of view.

Micromolding of Thermoplastic Polymers for Direct Fabrication of Discrete, Multilayered Microparticles

Soft lithography provides a convenient and effective method for the fabrication of microdevices with uniform size and shape. However, formation of an embossed, connective film as opposed to discrete features has been an enduring shortcoming associated with soft lithography. Removing this residual layer requires additional postprocessing steps that are often incompatible with organic materials. This limits adaptation and widespread realization of soft lithography for broader applications particularly in drug discovery and drug delivery fields. A novel and versatile approach is demonstrated that enables fabrication of discrete, multilayered, fillable, and harvestable microparticles directly from any thermoplastic polymer, even at very high molecular weights. The approach, isolated microparticle replication via surface-segregating polymer blend mold, utilizes a random copolymer additive, designed with a highly fluorinated segment that, when blended with the mold's matrix, spontaneously orients to the surface conferring an extremely low surface energy and nonwetting properties to the template. The extremely nonwetting properties of the mold are further utilized to load soluble biologics directly into the built-in microwells in a rapid and efficient manner using an innovative screen-printing approach. It is believed that this approach holds promise for fabrication of large-array, 3D, complex microstructures, and is a significant step toward clinical translation of microfabrication technologies.

The Role of Multiply-Fortified Table Salt and Bouillon in Food Systems Transformation

Our global food system lacks the critically needed micronutrients to meet the daily requirements of the most at-risk populations. Diets also continue to shift toward unhealthy foods, including the increased intake of salt. While most countries exceed the WHO’s recommended levels, sodium does play an essential physiological role. Table salt and other salt-containing condiments, such as bouillon, also have cultural importance, as they are used to enhance the flavor of foods cooked at home. Given their universal consumption across income classes and both urban and rural populations, these condiments are an integral part of the food system and should, therefore, be part of its transformation. Fortification of salt and salt-containing condiments can play a catalytic role in the delivery of population-wide nutritional and health benefits. With relatively consistent levels of intake across the population, these condiments hold high potential for delivering micronutrients beyond iodine while also reducing concerns related to high micronutrient intake, particularly so in countries where the industries are relatively consolidated. As a flexible and complementary strategy to an evolving food system, fortification levels can also be adjusted over time to ensure micronutrient delivery targets continue to be achieved as the system improves, whether through lower intakes of sodium in line with WHO recommendations, enhanced consumption of nutrient-dense foods, and/or broader adoption of biofortified crops. Future areas of innovation are required to realize this vision, including developing affordable salt substitutes to meet cost requirements of consumers in low-and middle-income countries, improving the stability and bioavailability of the micronutrients in condiments so that delivery targets can be reached without affecting sensory attributes, and the development of efficient systems for monitoring population intake and micronutrient status to inform fortification program design and management. Rather than being considered antithetical to the transformation, multiply-fortified salt and bouillon can strengthen our ability to meet the cultural, sensory, nutritional, and health needs of an evolving food system.

Effect of rice bran protein concentrate as wall material adjunct on selected physicochemical and release properties of microencapsulated β-carotene

Rice bran protein is an emerging protein source from rice milling that possesses health benefits and emulsifying capacity suitable for hypoallergenic encapsulation applications, especially for lipophilic compounds such as β-carotene. The purpose of this study is to develop and characterize β-carotene encapsulates with maltodextrin and rice bran protein. Rice bran protein was prepared using conventional alkali extraction. β-carotene was added to the composite wall materials (50:50 of 4%, 8%, 12%, and 16% solids content) and spray-dried. Encapsulation efficiency (85-98%) and radical scavenging activity (11-43%) varied proportionally with rice bran protein. Across increasing maltodextrin and rice bran protein content of the feed, carbohydrate content of the microcapsules varied proportionally (50-66%) but protein content was uniform (10-13%). Scanning electron microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy data suggested successful encapsulation. Release profiles showed decreasing trend with increasing rice bran protein content; co-digestion with rice mitigated negative impacts of rice bran protein. Microcapsules with nutritive potential and health-promoting properties were developed as potential carotenoid delivery systems.

Enhanced Storage of Anaerobic Bacteria through Polymeric Encapsulation

Live microbes such as lactobacilli have long been used as probiotic supplements and, more recently, have been explored as live biotherapeutic products with the potential to treat a range of conditions. Among these microbes is a category of anaerobes that possess therapeutic potential while exhibiting unique oxygen sensitivity and thus requiring careful considerations in the formulation and storage processes. Existing microbial formulation development has focused on facultative anaerobes with natural oxygen tolerance; a few strategies have been reported for anaerobes with demonstrated oxygen intolerance, warranting novel approaches toward addressing the challenges for these oxygen-sensitive anaerobes. Here, we develop a polymeric encapsulation system for the formulation and storage of Bifidobacterium adolescentis (B. adolescentis), a model anaerobe that loses viability in aerobic incubation at 37 °C within 1 day. We discover that this strain remains viable under aerobic conditions for 14 days at 4 °C, enabling formulation development such as solution casting and air drying in an aerobic environment. Next, through a systematic selection of polymer encapsulants and excipients, we show that encapsulation with poly(vinyl alcohol) (PVA) acts as an oxygen barrier and facilitates long-term storage of B. adolescentis, which is partially attributed to reduced generation of reactive oxygen species. Lastly, PVA-based formulations can produce oral capsule-loaded films and edible gummy bears, demonstrating its compatibility with both pharmaceutical and food dosage forms.

Hazard Analysis and Risk-Based Preventive Controls (HARPC): Current Food Safety and Quality Standards for Complementary Foods

Food safety is imperative, especially for infants and young children because of their underdeveloped immune systems. This requires adequate nutritious food with appropriate amounts of macro- and micronutrients. Currently, a well-established system for infant food is enforced by the regulatory bodies, but no clear system exists for complementary food, which is consumed by children from the age of 6 month to 24 months. As the child grows beyond 6 months, the need for nutrients increases, and if the nutritional needs are not fulfilled, it can lead to health problems, such as stunted growth, weak immune system, and cardiovascular diseases. Hence, it is important to have regulatory bodies monitoring complementary food in a similar capacity as is required for infant formula. The objective of this review is to provide an overview of the existing regulatory bodies, such as the Codex Alimentarius, International Standard Organization (ISO), Food and Drug Administration (FDA), etc., and their regulations specifically for infant formula that can be adopted for complementary foods. This study focuses on the development of a hazard analysis and risk-based preventive controls (HARPC)-based food safety plan to ensure safe food processing and prevent any possible outbreaks.

Carbohydrate-Based Macromolecular Biomaterials

Carbohydrates are the most abundant and one of the most important biomacromolecules in Nature. Except for energy-related compounds, carbohydrates can be roughly divided into two categories: Carbohydrates as matter and carbohydrates as information. As matter, carbohydrates are abundantly present in the extracellular matrix of animals and cell walls of various plants, bacteria, fungi, etc., serving as scaffolds. Some commonly found polysaccharides are featured as biocompatible materials with controllable rigidity and functionality, forming polymeric biomaterials which are widely used in drug delivery, tissue engineering, etc. As information, carbohydrates are usually referred to the glycans from glycoproteins, glycolipids, and proteoglycans, which bind to proteins or other carbohydrates, thereby meditating the cell-cell and cell-matrix interactions. These glycans could be simplified as synthetic glycopolymers, glycolipids, and glycoproteins, which could be afforded through polymerization, multistep synthesis, or a semisynthetic strategy. The information role of carbohydrates can be demonstrated not only as targeting reagents but also as immune antigens and adjuvants. The latter are also included in this review as they are always in a macromolecular formulation. In this review, we intend to provide a relatively comprehensive summary of carbohydrate-based macromolecular biomaterials since 2010 while emphasizing the fundamental understanding to guide the rational design of biomaterials. Carbohydrate-based macromolecules on the basis of their resources and chemical structures will be discussed, including naturally occurring polysaccharides, naturally derived synthetic polysaccharides, glycopolymers/glycodendrimers, supramolecular glycopolymers, and synthetic glycolipids/glycoproteins. Multiscale structure-function relationships in several major application areas, including delivery systems, tissue engineering, and immunology, will be detailed. We hope this review will provide valuable information for the development of carbohydrate-based macromolecular biomaterials and build a bridge between the carbohydrates as matter and the carbohydrates as information to promote new biomaterial design in the near future.

Direct assessment of body iron balance in women with and without iron supplementation using a long-term isotope dilution method in Benin and Switzerland

BACKGROUND

Long-term isotopic dilution measurements of body iron may allow quantification of basal body iron balance and iron gains during an iron intervention with higher precision and accuracy than conventional iron indices.

OBJECTIVES

We compared body iron balance before, during, and after oral iron supplementation in women in Benin and in Switzerland.

METHODS

In prospective studies, Beninese (n = 11) and Swiss (n = 10) women previously labeled with stable iron isotopes were followed preintervention for 90-120 d, then received 50-mg iron daily for 90-120 d and were followed postintervention for 90-120 d. We used changes in blood isotopic composition to calculate iron absorption (Feabs), iron loss (Feloss), and net iron balance (Fegain).

RESULTS

Compliance with supplementation was >90%. In Benin, during the preintervention, intervention, and postintervention periods, Fe means ± SDs were as follows: 1) Feabs: 0.92 ± 1.05, 3.75 ± 2.07, and 0.90 ± 0.93 mg/d; 2) Feloss: 1.46 ± 1.95, 1.58 ± 1.57, and 1.84 ± 1.61 mg/d; and 3) Fegain: -0.55 ± 1.56 mg/d, 2.17 ± 1.81 mg/d, and -0.94 ± 1.13 mg/d. In Switzerland, the corresponding values were: 1) 1.51 ± 0.37, 4.09 ± 1.52, and 0.97 ± 0.41 mg/d; 2) 0.76 ± 1.37, 2.54 ± 1.43, and 2.08 ± 1.05 mg/d; and 3) 0.75 ± 1.37, 1.55 ± 1.75, and -1.11 ± 1.06 mg/d. Inflammation was low in both settings, and isotopically calculated iron balance was comparable to that calculated from changes in conventional iron indices.

CONCLUSION

Without iron supplementation, Beninese women had lower long-term dietary iron absorption and higher iron losses in the preintervention period than Swiss women. During iron supplementation, both groups had high iron absorption and similar iron gains. However, there was a 3-fold increase in iron losses in the Swiss women during the supplementation and postintervention period compared with the preintervention period. Body iron isotope dilution is a promising new method for quantifying long-term body iron balance and for assessing the impact of iron interventions. The studies were registered at clinicaltrials.gov as NCT02979080 and NCT02979132, respectively.

Insight into the structural, chemical and surface properties of proteins for the efficient ultrasound assisted co-encapsulation and delivery of micronutrients

Three different proteinaceous biopolymers, namely, egg white protein (EWP), soy protein isolate (SPI) and corn protein isolate (CPI) were used as protective shell materials to encapsulate micronutrients via an ultrasonic encapsulation technique. It was found that the physicochemical properties of the three protein-based matrices, including surface/total thiol (-SH) content, surface activity and denaturation temperature were the key factors that influenced the shell formation and stability. The EWP and CPI-shelled microcapsules reduced the degradation of the encapsulated vitamins by 20% and 40% after exposure to heating and UV-light irradiation. A double emulsion technique was further developed to co-encapsulate both oil- (vitamin A and D) and water-soluble (vitamin B, C and minerals) micronutrients. In-vitro digestion study showed that the proteinaceous microcapsules enable a sustained release of micronutrients, demonstrating their potential for food fortification applications.

Ultrasonic microencapsulation of oil-soluble vitamins by hen egg white and green tea for fortification of food

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Highly stable vitamin loaded microcapsules are synthesised by ultrasound.

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Egg white proteins provide robust shells to protect vitamins from degradation.

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External green tea/iron coating imparts UV filtering property to microcapsules.

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Microcapsules maintain structural integrity during food fortification.

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In-vitro digestion model shows the effective release of the encapsulated vitamin.

We report the microencapsulation of oil soluble vitamins (A, D and E) using a one pot ultrasonic process and raw egg white proteins as a shell material. Green tea catechin/iron complex coating method was further developed to impart UV filtering property to the microcapsules in order to protect the encapsulated nutrients from photodegradation. The microcapsules showed antibacterial properties and long shelf-life. The encapsulated vitamins were protected from degradation upon heating, UV irradiation, simulated storage/transit and cooking processes. The in-vitro digestion study showed that functional vitamin D can be potentially released in the gastrointestinal tract improving vitamin D availability by more than 2-fold compared to the free vitamin. The vitamin D microcapsules were highly stable and maintained their microstructures once incorporated into staple food products. The low-cost egg white shell encapsulated vitamins can improve the nutritional value of staple food products to combat maternal and child malnutrition.

Nano-enabled personalized nutrition: Developing multicomponent-bioactive colloidal delivery systems

There is growing interest in the production of foods and beverages with nutrient and nutraceutical profiles tailored to an individual's specific nutritional requirements. In principle, these personalized nutrition products are formulated based on the genetics, epigenetics, metabolism, microbiome, phenotype, lifestyle, age, gender, and health status of a person. A challenge in this area is to create customized functional food and beverage products that contain the required combination of bioactive agents, such as lipids, proteins, carbohydrates, vitamins, minerals, nutraceuticals, prebiotics and probiotics. Nanotechnology may facilitate the development of these kind of products since it can be used to encapsulate one or more bioactive agent in a single colloidal delivery system. This delivery system may contain one or more different kinds of colloidal particle, specifically designed to protect each nutrient in the food, but then deliver it in a bioavailable form after ingestion. This review article provides an overview of the different kinds of bioactives that need to be delivered, as well as some of the challenges associated with incorporating them into functional foods and beverages. It then highlights how nanotech-enabled colloidal delivery systems can be developed to encapsulate multiple bioactive agents in a form suitable for functional food applications, particularly in the personalized nutrition field.

Micro and nanoscale technologies in oral drug delivery

Oral administration is a pillar of the pharmaceutical industry and yet it remains challenging to administer hydrophilic therapeutics by the oral route. Smart and controlled oral drug delivery could bypass the physiological barriers that limit the oral delivery of these therapeutics. Micro- and nanoscale technologies, with an unprecedented ability to create, control, and measure micro- or nanoenvironments, have found tremendous applications in biology and medicine. In particular, significant advances have been made in using these technologies for oral drug delivery. In this review, we briefly describe biological barriers to oral drug delivery and micro and nanoscale fabrication technologies. Micro and nanoscale drug carriers fabricated using these technologies, including bioadhesives, microparticles, micropatches, and nanoparticles, are described. Other applications of micro and nanoscale technologies are discussed, including fabrication of devices and tissue engineering models to precisely control or assess oral drug delivery in vivo and in vitro, respectively. Strategies to advance translation of micro and nanotechnologies into clinical trials for oral drug delivery are mentioned. Finally, challenges and future prospects on further integration of micro and nanoscale technologies with oral drug delivery systems are highlighted.

Parallel evolution of polymer chemistry and immunology: Integrating mechanistic biology with materials design

To develop new therapeutics involves the interaction of multiple disciplines to yield safe, functional devices and formulations. Regardless of drug function and potency, administration with controlled timing, dosing, and targeting is required to properly treat or regulate health and disease. Delivery approaches can be optimized through advances in materials science, clinical testing, and basic biology and immunology. Presently, laboratories focused on developing these technologies are composed of, or collaborate with, chemists, biologists, materials scientists, engineers, and physicians to understand the way our body interacts with drug delivery devices, and how to synthesize new, rationally designed materials to improve targeted and controlled drug delivery. In this review, we discuss both device-based and micro/nanoparticle-based materials in the clinic, our biologic understanding of how our immune system interacts with these materials, how this diverse set of immune cells has become a target and variable in drug delivery design, and new directions in polymer chemistry to address these interactions and further our advances in medical therapeutics.

Controlling the movement of molecules

The ability to control the movement of molecules is both fascinating scientifically as well as being critically important to the well-being of our planet and its people. In particular, the sustained release of molecules over prolonged periods at controlled rates has had and will continue to have enormous implications for the delivery of substances in medicine, agriculture, the environment, nutrition, aquaculture, household consumer products, and numerous other areas. This field is advancing at a rapidly accelerating pace. In this article, I largely discuss our own work, starting 45 years ago, in enabling the controlled release of macromolecules from biocompatible polymers. I also discuss the synthesis of novel materials to affect molecular movement and I then examine external approaches for controlling the movement of molecules through materials, using forces such as electric, acoustic, and magnetic fields. I further discuss approaches for controlling molecular movement through physiologic barriers, such as the skin, lung, and intestine. Finally, I outline several future areas of this field, including how it can affect the developing world, the ability to control the movement of molecules into mammalian cells, and the design of intelligent approaches to control molecular delivery.