Potential biological fate of ingested nanoemulsions: influence of particle characteristics

Edible nanoemulsions have great potential for utilization in the food and beverage industries to encapsulate, protect, and deliver lipophilic functional components claimed to have health benefits ("nutraceuticals"), such as carotenoids, flavonoids, phytosterols, polyunsaturated lipids, and oil-soluble vitamins. Nanoemulsions have a number of possible advantages over conventional emulsions for these applications, including high optical clarity, high stability to particle aggregation and gravitational separation, and increased bioavailability of lipophilic substances. Nevertheless, there are concerns about the potential risks associated with ingestion of nanoemulsions due to their ability to alter the behavior of bioactive components within the gastrointestinal tract. At present, there is still a relatively poor understanding of the biological fate of nanoemulsions in the human GI tract, which is holding back the rational design and application of nanoemulsion-based delivery systems for lipophilic bioactive components. This article provides a brief review of the current status of the formation, properties, and potential biological fate of food-grade nanoemulsions. In particular, it focuses on the influence of particle characteristics, such as size and interfacial properties, on the digestion and absorption of lipid nanoparticles.     

Recent advances on protein‐based Pickering high internal phase emulsions (Pickering HIPEs): Fabrication,characterization, and applications

Most trans fats in processed foods come from partially hydrogenated oils (PHOs). Numerous studies have shown that the excessive intake of trans fats may cause some adverse effects on human health. An effective alternative to PHOs is to construct Pickering high internal phase emulsions (HIPEs). In recent years, considerable attention has been paid to Pickering HIPEs stabilized by protein‐based particles because of their high stability and promising applications in the fields of food, cosmetics, and pharmaceutical industries. This review summarizes the recent progress of Pickering HIPEs stabilized by protein‐based particles focusing on the methods for their preparation and characterization, and discusses the applications of Pickering HIPEs in the food industry. Promising research trends in this field are also proposed, including (a) developing protein‐based antioxidant Pickering HIPEs and Pickering nanoemulsions, and (b) expanding the potential applications of protein‐based Pickering HIPEs in the fields of delivery vehicles, the template for porous materials, and biodegradable packaging films. This review will provide a theoretical basis for future technological innovation and application development of protein‐based Pickering HIPEs.     

Essential Oils: Extraction,Bioactivities, and Their Uses for Food Preservation

Essential oils are concentrated liquids of complex mixtures of volatile compounds and can be extracted from several plant organs. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties. In addition, some essential oils have been used as medicine. Furthermore, the uses of essential oils have received increasing attention as the natural additives for the shelf‐life extension of food products, due to the risk in using synthetic preservatives. Essential oils can be incorporated into packaging, in which they can provide multifunctions termed “active or smart packaging.” Those essential oils are able to modify the matrix of packaging materials, thereby rendering the improved properties. This review covers up‐to‐date literatures on essential oils including sources, chemical composition, extraction methods, bioactivities, and their applications, particularly with the emphasis on preservation and the shelf‐life extension of food products.     

Formation of Food‐Grade Nanoemulsions Using Low‐Energy Preparation Methods: A Review of Available Methods

There is considerable interest in the production of emulsions and nanoemulsions using low‐energy methods due to the fact they are simple to implement and no expensive equipment is required. In this review, the principles of isothermal (spontaneous emulsification and emulsion phase inversion) and thermal (phase inversion temperature) low‐energy methods for nanoemulsion production are presented. The major factors influencing nanoemulsion formation using low‐energy methods and food‐grade components are reviewed: preparation conditions, oil type, surfactant type, surfactant‐to‐oil ratio, and cosolvent or cosurfactant addition. The advantages and disadvantages of different low‐energy and high‐energy methods for fabricating nanoemulsions are highlighted, and potential applications for these techniques are discussed.     

Prevention of fungal spoilage in food products using natural compounds: A review

The kingdom Fungi is the most important group of microorganism contaminating food commodities, and chemical additives are commonly used in the food industry to prevent fungal spoilage. However, the increasing consumer concern about synthetic additives has led to their substitution by natural compounds in foods. The current review provides an overview of using natural agents isolated from different sources (plants, animals, and microorganisms) as promising antifungal compounds, including information about their mechanism of action and their use in foods to preserve and prolong shelf life. Compounds derived from plants, chitosan, lactoferrin, and biocontrol agents (lactic acid bacteria, antagonistic yeast, and their metabolites) are able to control the decay caused by fungi in a wide variety of foods. Several strategies are employed to reduce the drawbacks of some antifungal agents, like their incorporation into oil-in-water emulsions and nanoemulsions, edible films and active packaging, and their combination with other natural preservatives. These strategies facilitate the addition of volatile agents into food products and, improve their antifungal effectiveness. Moreover, biological agents have been investigated as one of the most promising options in the control of postharvest decay. Numerous mechanisms of action have been elucidated and different approaches have been studied to enhance their antifungal effectiveness.     

Review on the Stability Mechanism and Application of Water‐in‐Oil Emulsions Encapsulating Various Additives

Water‐in‐oil (W/O) emulsions can be used to encapsulate and control the release of bioactive compounds for nutrition fortification in fat‐based food products. However, long‐term stabilization of W/O emulsions remains a challenging task in food science and thereby limits their potential application in the food industry. To develop high‐quality emulsion‐based food products, it is essential to better understand the factors that affect the emulsions’ stability. In real food system, the stability situation of W/O emulsions is more complicated by the fact that various additives are contained in the products, such as NaCl, sugar, and other large molecular additives. The potential stability issues of W/O emulsions caused by these encapsulated additives are a current concern, and special attention should be given to the relevant theoretical knowledge. This article presents several commonly used methods for the preparation of W/O emulsions, and the roles of different additives (water‐ and oil‐soluble types) in stabilizing W/O emulsions are mainly discussed and illustrated to gain new insights into the stability mechanism of emulsion systems. In addition, the review provides a comprehensive and state‐of‐art overview of the potential applications of W/O emulsions in food systems, for example, as fat replacers, controlled‐release platforms of nutrients, and delivery carrier systems of water‐soluble bioactive compounds. The information may be useful for optimizing the formulation of W/O emulsions for utilization in commercial functional food products.     

Food-grade nanoemulsions: formulation, fabrication, properties, performance, biological fate, and potential toxicity

Nanoemulsions fabricated from food-grade ingredients are being increasingly utilized in the food industry to encapsulate, protect, and deliver lipophilic functional components, such as biologically-active lipids (e.g., ω-3 fatty acids, conjugated linoleic acid) and oil-soluble flavors, vitamins, preservatives, and nutraceuticals. The small size of the particles in nanoemulsions (r<100 nm) means that they have a number of potential advantages over conventional emulsions-higher stability to droplet aggregation and gravitational separation, high optical clarity, ability to modulate product texture, and, increased bioavailability of lipophilic components. On the other hand, there may also be some risks associated with the oral ingestion of nanoemulsions, such as their ability to change the biological fate of bioactive components within the gastrointestinal tract and the potential toxicity of some of the components used in their fabrication. This review article provides an overview of the current status of nanoemulsion formulation, fabrication, properties, applications, biological fate, and potential toxicity with emphasis on systems suitable for utilization within the food and beverage industry.     

Olive byproducts and their bioactive compounds as a valuable source for food packaging applications

Among the most important agro-industrial activities in the Mediterranean basin, olive oil production has a high impact on the economy of many Mediterranean countries. However, olive oil extraction generates huge quantities of byproducts, including leaves, pomace residues, stones and wastewater, which have severe environmental impacts mainly because of their phytotoxicity and great organic content. Olive oil byproducts are regarded as inexpensive and abundant raw materials rich in bioactive compounds with high and varied health-related activities. Several phenolic compounds and terpenoids were recovered from olive byproducts using different conventional and advanced extraction methods due to their potential to be used in food, packaging, pharmaceutical, and cosmetic industries. Recently, the use of olive byproducts and their functional compounds to enhance the functional properties of packaging systems was investigated as a sustainable strategy for food preservation, fostering the sustainability of the olive-oil chain, and promoting circular economy. In this framework, the main goals of this review are to summarize the main bioactive compounds in olive byproducts, to review the main advancements in their extraction, purification, and characterization, and finally to discuss their applications in food packaging systems as well as safety-related aspects.     

Electrospinning of nanofibers: Potentials and perspectives for active food packaging

Electrospun nanofibers with structural and functional advantages have drawn much attention due to their potential applications for active food packaging. The traditional role of food packaging is just storage containers for food products. The changes of retailing practice and consumer demand promote the development of active packaging to improve the safety, quality, and shelf life of the packaged foods. To develop the technique of electrospinning for active food packaging, electrospun nanofibers have been covalently or non‐covalently functionalized for loading diverse bioactive compounds including antimicrobial agents, antioxidant agents, oxygen scavengers, carbon dioxide emitters, and ethylene scavengers. The aim of this review is to present a concise but comprehensive summary on the progress of electrospinning techniques for active food packaging. Emphasis is placed on the tunability of the electrospinning technique, which achieves the modification of fiber composition, orientation, and architecture. Efforts are also made to provide functionalized strategies of electrospun polymeric nanofibers for food packaging application. Furthermore, the existing limitations and prospects for developing electrospinning in food packaging area are discussed.     

Migration of Chemical Compounds from Packaging Polymers during Microwave,Conventional Heat Treatment,and Storage

Polymeric packaging protects food during storage and transportation, and withstands mechanical and thermal stresses from high‐temperature conventional retort or microwave‐assisted food processing treatments. Chemical compounds that are incorporated within polymeric packaging materials to improve functionality, may interact with food components during processing or storage and migrate into the food. Once these compounds reach a specified limit, food quality and safety may be jeopardized. Possible chemical migrants include plasticizers, antioxidants, thermal stabilizers, slip compounds, and monomers. Chemical migration from food packaging is affected by a number of parameters including the nature and complexity of food, the contact time and temperature of the system, the type of packaging contact layer, and the properties of the migrants. Researchers study the migration of food‐packaging compounds by exposing food or food‐simulating liquids to conventional and microwave heating and storage conditions, primarily through chromatographic or spectroscopic methods; from these data, they develop kinetic and risk assessment models. This review provides a comprehensive overview of the migration of chemical compounds into food or food simulants exposed to various heat treatments and storage conditions, as well as a discussion of regulatory issues.     

A novel nanoemulsification method of stirring at the Θ-point with the tocopherol-based block co-polymer nonionic emulsifier PPG-20 Tocophereth-50

Nanoemulsions have recently become increasingly important as potential vehicles for the controlled delivery of cosmetics and for the optimized dispersion of active ingredients in particular skin layers. The preparation of conventional nanoemulsions requires mainly high‐pressure homogenization, which is unproductive and requires high energy due to its lower efficiency, limiting their practical applications. In order to solve these problems novel nanoemulsions were studied using a model system of pseudo‐ternary water/emulsifier/paraffin oil. Nanoemulsions were prepared by stirring a mixture of the tocopherol‐containing block co‐polymer emulsifier PPG‐20 Tocophereth‐50, paraffin oil, and distilled water at the Θ‐point using weight fractions of the dispersed phase (φ) of 0.31 to 0.82 and an emulsifier content of 1.0 to 9 wt.%. The emulsifying property of PPG‐20 Tocophereth‐50 in nanoemulsions was compared with that of the conventional emulsifiers Tocophereth‐43, a mixture of polysorbate 60 and sesquioleate (3/1), and phospholipids. Also the emulsifying property of PPG‐20 Tocophereth‐50 in the more hydrophilic oils caprylic/capric triglyceride and octyldodecanol was compared with that in paraffin oil. The stability and morphology of the resulting nanoemulsions were studied by visual inspection, optical microscopy, particle size analysis, and cryo‐scanning electron microscopy. In the nanoemulsion systems containing caprylic/capric triglyceride and octyldodecanol, respectively, as an oil phase PPG‐20 Tocophereth‐50 showed emulsification properties similar to those in paraffin oil. The conventional emulsifiers Tocophereth‐43, a mixture of polysorbate 60 and sesquioleate (3/1), and phospholipids did not give nanoemulsions with high‐speed stirring. The block co‐polymer nonionic emulsifier PPG‐20 Tocophereth‐50 was found to produce stable nanoemulsions of mean droplet diameters ranging from 204 to 499 nm. The emulsification method of high‐speed stirring at the Θ‐point using PPG‐20 Tocophereth‐50 was found to be very effective for the preparation of stable nanoemulsions useful for applications in skincare cosmetics, cosmeceuticals, and drugs.     

纳米粒子稳定的Pickering乳液在食品包装中的应用研究进展

Pickering乳液是以超细固体颗粒作为乳化剂制得的乳状液,具有乳化剂用量低、稳定性高、环境友好等优点,同时对活性物质具有良好的包载、缓释能力,在食品包装领域应用前景广阔。本文介绍了4种食品级天然纳米粒子（蛋白、多糖、脂质和多酚）稳定Pickering乳液的机理及其应用效果;综述了Pickering乳液在食品包装中的应用研究现状,基于机械性能、阻隔性能、抑菌和抗氧化性能等方面分析了Pickering乳液的加入对食品包装膜品质的影响;并对Pickering乳液在食品包装领域的研究方向进行了展望,以期推动Pickering乳液在食品包装领域的研究和应用。     

Study of the Emulsifying Ability of Olive Oil Endogenous Compounds in Co-surfactant Free Olive Oil w/o Nanoemulsions with Food Grade Non-ionic Surfactants

In the present work, the preparation of olive oil w/o nanoemulsions was studied using non-ionic surfactants (Tween 20, Span 20) without the addition of a co-surfactant. Different olive oil endogenous compounds with an amphiphilic character (gallic acid, apigenin, quercetin, and trans-cinnamic acid) were dispersed into the aqueous phase, and their impact on the nanoemulsions stability and properties ability was determined. The stable nanoemulsions were presented in pseudo-ternary phase diagrams (oil–aqueous phase–surfactant) for each surfactant and endogenous compound. The nanoemulsions properties were evaluated in relationship to compositional components. The results of this study concluded that stable w/o olive oil nanoemulsions without use of a co-surfactant were obtained and moreover, the most efficient type of emulsifier and its ratio of addition in the system were determined. The incorporation of olive oil endogenous compounds resulted into more stable emulsions. In particular, gallic acid was proven to be the most efficient compound since it enhanced the emulsion properties prolonging simultaneously the emulsions’ stability.     

Oxidation and oxidative stability in emulsions

Emulsions are implemented in the fabrication of a wide array of foods and therefore are of great importance in food science. However, the application of emulsions in food production is restricted by two main obstacles, that is, physical and oxidative stability. The former has been comprehensively reviewed somewhere else, but our literature review indicated that there is a prominent ground for reviewing the latter across all kinds of emulsions. Therefore, the present study was formulated in order to review oxidation and oxidative stability in emulsions. In doing so, different measures to render oxidative stability to emulsions are reviewed after introducing lipid oxidation reactions and methods to measure lipid oxidation. These strategies are scrutinized in four main categories, namely storage conditions, emulsifiers, optimization of production methods, and antioxidants. Afterward, oxidation in all types of emulsions, including conventional ones (oil-in-water and water-in-oil) and uncommon emulsions in food production (oil-in-oil), is reviewed. Furthermore, the oxidation and oxidative stability of multiple emulsions, nanoemulsions, and Pickering emulsions are taken into account. Finally, oxidative processes across different parent and food emulsions were explained taking a comparative approach.     

水包油型食品乳液中天然小分子乳化剂的功能性质及与其他乳化剂相互作用关系的研究进展

水包油型乳液是食品、保健品、药品等的重要成分,单一或复合乳化剂对水包油型乳液的形成、稳定性和功能性质有重要影响。如今消费者对健康和环境保护的关注促使食品生产者更倾向使用天然成分取代合成成分。本文综述在食品工业中具有潜在应用价值小分子天然乳化剂的理化性质,讨论其对乳液稳定性的影响以及在食品工业中的应用情况,并总结在乳液中使用复合乳化剂,尤其是磷脂与其他乳化剂相互作用的性质和机理;最后概括复合乳化剂对乳液功能性质的影响,包括抗氧化活性、抗菌活性和胃肠道消化特性。以期为开发乳液产品、选择乳化剂及其组合提供理论参考。     

Advancements in liposome technology: Preparation techniques and applications in food,functional foods,and bioactive delivery: A review

Liposomes play a significant role in encapsulation of various bioactive compounds (BACs), including functional food ingredients to improve the stability of core. This technology can be used for promoting an effective application in functional food and nutraceuticals. Incorporation of traditional and emerging methods for the developments of liposome for loading BACs resulted in viable and stable liposome formulations for industrial applications. Thus, the advance technologies such as supercritical fluidic methods, microfluidization, ultrasonication with traditional methods are revisited. Liposomes loaded with plant and animal BACs have been introduced for functional food and nutraceutical applications. In general, application of liposome systems improves stability, delivery, and bioavailability of BACs in functional food systems and nutraceuticals. This review covers the current techniques and methodologies developed and practiced in liposomal preparation and application in functional foods.     

Ice Cream as a Vehicle for Incorporating Health‐Promoting Ingredients: Conceptualization and Overview of Quality and Storage Stability

Ice cream is a product with peculiar textural and organoleptic features and is highly appreciated by a very broad spectrum of consumers. Ice cream's structure and colloidal design, together with its low‐temperature storage, renders it a very promising carrier for the stabilization and in vivo delivery of bioactive compounds and beneficial microorganisms. To date, many applications related to the design and development of functional ice cream have been documented, including products containing probiotics, prebiotics, synbiotics, dietary fibers, natural antioxidants such as polyphenols, essential and polyunsaturated fatty acids, and low glycemic index blends and blends fortified with mineral or trace elements. In this review, promising strategies for the incorporation of innovative functional additives to ice cream through the use of techniques such as microencapsulation, nanoemulsions, and oleogels are discussed, and current insights into the implications of matrix, processing, and digestion on bioactive compounds in frozen dairy desserts are comprehensively reviewed, thereby providing a holistic overview of the current and emerging trends in this functional food sector.     

蛋白质基Pickering乳液的研究进展

由于Pickering乳液的优良环保性、抗聚结稳定性以及在生物活性药物输送方面的潜在应用,其在化妆品、食品等领域受到广泛关注。相比较于传统乳液,Pickering乳液不含任何表面活性剂,具有安全稳定的特性。考虑到毒性和食品安全问题,无机粒子和合成粒子的应用受到很大限制。在稳定乳液方面,Pickering粒子在界面处的吸附几乎是不可逆的,因此,有必要寻找更合适的食品级Pickering粒子。该文综述了Pickering乳液的稳定机制,包括粒子润湿性、三相接触角、粒子形成的空间位阻,以及近年来蛋白质和蛋白质基的Pickering颗粒及其稳定Pickering乳液的生产、表征及稳定性等方面的最新进展,并讨论其发展方向,为进一步扩大蛋白质纳米粒子在食品领域中的应用奠定基础。     

Food Packaging: A Comprehensive Review and Future Trends

Innovations in food packaging systems will help meet the evolving needs of the market, such as consumer preference for “healthy” and high‐quality food products and reduction of the negative environmental impacts of food packaging. Emerging concepts of active and intelligent packaging technologies provide numerous innovative solutions for prolonging shelf‐life and improving the quality and safety of food products. There are also new approaches to improving the passive characteristics of food packaging, such as mechanical strength, barrier performance, and thermal stability. The development of sustainable or green packaging has the potential to reduce the environmental impacts of food packaging through the use of edible or biodegradable materials, plant extracts, and nanomaterials. Active, intelligent, and green packaging technologies can work synergistically to yield a multipurpose food‐packaging system with no negative interactions between components, and this aim can be seen as the ultimate future goal for food packaging technology. This article reviews the principles of food packaging and recent developments in different types of food packaging technologies. Global patents and future research trends are also discussed.     

纳米纤维素在食品行业中应用研究进展

概述了纳米纤维素的种类,包括微纤化纤维素、纳米纤维素晶体和细菌纳米纤维素,以及3种纳米纤维素的特性及其主要制备方法;重点介绍了纳米纤维素在食品领域的应用,主要包括其作为食品添加剂、功能性食品成分及食品包装材料等其他用途,并对其未来发展进行展望。