Microencapsulation of Natural Antioxidant Compounds Obtained from Biomass Wastes: A Review

Abstract

Growing interest in biomass valorisation in recent years has led to an increasing research focusing on its high content in phytochemicals showing high potential health benefits related to their antioxidant, anti-inflammatory and antibacterial properties, among others. On the other hand, the demand for natural antioxidants in industry is continuously increasing to avoid the harmless character of some chemical additives and, also, to limit oxidation processes in the final material, such as in food and cosmetics; increasing consumer acceptance. However, the majority of them are usually sensitive to several factors such as oxygen, light, heat, enzymes, salts, and acid or alkali mediums which lead to losses of their activity and beneficial effects. As a consequence, microencapsulation technique has been proposed in last years as a way to enhance the stability, solubility and bioavailability of these compounds. In this chapter, phytochemical compounds classification followed by their main characteristics and properties are summarized. Also, microencapsulation techniques for phytochemicals are reviewed including processes for preparing microparticles, mainly focused on spray-drying method, for industry applications.

Novel Approaches in the Valorization of Agricultural Wastes and Their Applications

“…The valorization of biomass by conventional methods such as solid–liquid extraction after maceration and novel and green methods such as extraction with sonication, supercritical fluids, microwaves, and pulsed electric fields recently attracted attention, because of their high phytochemical content, which provides antioxidant, anti-inflammatory, and antibacterial properties leading to potential health benefits. , For instance, these health-promoting bioactive compounds in fruit and vegetable wastes play an essential role in their anticancer, antimutagenic, antiviral, antioxidant, antitumor activities and their ability to reduce the risks of cardiometabolic diseases. Also, recent studies focusing on phytochemicals state that the high antioxidant properties of polyphenols from plant sources, including skins, seeds, pulp, or pomace, make polyphenols one of the primary phytochemicals important for health aspects …”

“…Although the demand and consumer acceptance for natural antioxidants in the food industry are constantly increasing to prevent harmful chemical additives and inhibit the oxidation processes in the final product, there are several problems with the utilization of natural antioxidants in various food products. , Most of them are challenged by chemical degradation in foods and the gastrointestinal tract (GIT), reducing their bioavailability and bioactivity . In addition, many of them have a poor solubility problem, leading to a restriction of their direct incorporation in some foods, and many of them struggle with sensitivity to oxygen, light, heat, enzymes, salts, and acid or alkaline media, causing losses in their beneficial effects and activity . In recent years, scientists have performed extensive research to increase the amount and bioavailability of the components obtained from food wastes/byproducts and improve their stability during food processing and gastrointestinal digestion.…”

“…Nanotechnology can be defined as a technique developed to study, design, create, synthesize, apply and manipulate materials, devices, and functional systems by using nanoscale control of materials . Recently, microencapsulation and nanoencapsulation techniques have been applied for biomass wastes to find solutions to previously explained problems by increasing their stability, solubility, and bioavailability. , Within the scope of nanoencapsulation, edible nanoparticles, with a maximum particle size of 500 nm and composed of proteins, carbohydrates, lipids, phospholipids, or surfactants, trap the phytochemicals inside with different applications like spray drying, freeze-drying, coacervation, crystallization, molecular encapsulation, extrusion, and electrostatic extrusion to increase the efficiency and management of the phytochemicals by enhancing their stability, bioavailability, bioactivity, and dispersibility. , …”

“…87 In addition, many of them have a poor solubility problem, leading to a restriction of their direct incorporation in some foods, and many of them struggle with sensitivity to oxygen, light, heat, enzymes, salts, and acid or alkaline media, causing losses in their beneficial effects and activity. 88 In recent years, scientists have performed extensive research to increase the amount and bioavailability of the components obtained from food wastes/ byproducts and improve their stability during food processing and gastrointestinal digestion. The most common novel techniques to overcome these limitations are applied by nanotechnological approaches such as encapsulation, nanoemulsion, and biotechnological processes such as fermentation and enzyme use.…”

“…90 Recently, microencapsulation and nanoencapsulation techniques have been applied for biomass wastes to find solutions to previously explained problems by increasing their stability, solubility, and bioavailability. 87,88 Within the scope of nanoencapsulation, edible nanoparticles, with a maximum particle size of 500 nm and composed of proteins, carbohydrates, lipids, phospholipids, or surfactants, trap the phytochemicals inside with different applications like spray drying, freeze-drying, coacervation, crystallization, molecular encapsulation, extrusion, and electrostatic extrusion to increase the efficiency and management of the phytochemicals by enhancing their stability, bioavailability, bioactivity, and dispersibility. 87,89 Since nanotechnological approaches provide higher stability, bioaccessibility, and bioavailability for bioactive compounds, they can potentially lead to innovative and functional products, especially in the food and pharmaceutical industries.…”