Hydrocolloid Gel Particles: Formation, Characterization, and Application

Abstract

Hydrocolloid gel particles of micron and sub-micron size are particularly attractive for use in many applications in the food, agricultural, pharmaceutical, and chemical industries, due to their biocompatibility, perception as "natural" materials, and soft-solid texture. Industrial applications for such particles include uses as texturizers in confectionery and cosmetic products, slow-release encapsulation agents for flavors, nutrients, and pharmaceutical products, and thickeners in soups and sauces. Properties such as particle size, hardness, shape, texture, and molecular release rates can be important for individual applications. In addition, product formats will determine specific needs for physical form (e.g. dry or wet) and compatibility with other components. The diverse range of potential applications for hydrocolloid gel particles provide a driver for understanding-led tailoring of raw material and process conditions. This review introduces some of the materials that are used to form hydrocolloid gel particles and the corresponding gel formation mechanisms. One issue of importance in the production of hydrocolloid gel particles is the control of particle properties, such as release profiles, strength, and detectability within products. An alternative technique to traditional methods of hydrocolloid gel particle production is evaluated and a model for control of particle size, and subsequently other particle properties, is proposed. Key properties of hydrocolloid gel particles are identified and characterization methods for evaluating these properties are described.

Mango pulp-agar based model gel: textural characterisation

“…The main mechanisms for gelation of hydrocolloids are the ionotropic gelation, cold-set gelation and heat-set gelation (Burey et al 2008). Pappas et al (1987) investigated the development and characterization of agar gels.…”

Microencapsulation of probiotics using sodium alginate

“…The hardening of the capsules results from the addition, under magnetic agitation, of a solution of calcium chloride (HEIDEBACH et al, 2012). Subsequently, the gelation is initiated by reducing the pH by adding an acid solution, which in turn causes the release of calcium ions, allowing the complexation of calcium to the carboxylic groups of the polymer (BUREY et al, 2008).…”

“…Particles produced by extrusion typically present diameters ranging from 500μm to 3mm, and the size of the particles formed is dependent on the size of the diameter of the needle used to drip the solution, the viscosity and concentration of the alginate solution, besides the distance between the syringe and the solution of calcium chloride (BUREY et al, 2008).…”

Structured biopolymer-based delivery systems for encapsulation, protection, and release of lipophilic compounds

“…Some of the most common gelation methods include cold-setting gels and heat-setting gels (Morris, 2007). Ionotropic gelation is also another important gelling mechanism for polysaccharides (Burey et al, 2008). Some types of modified cellulose will self-associate upon heating, which has been attributed to an increase in the strength of the hydrophobic attraction between them.…”

“…These systems should be prepared from food-grade ingredients using economical and reliable processing operations. One of the most promising approaches to create food-grade colloidal particles is to use biopolymers, such as proteins and polysaccharides, as building blocks (Benichou, Aserin, & Garti, 2002;Burey, Bhandari, Howes, & Gidley, 2008;Chen, Remondetto, & Subirade, 2005;Dickinson, 2003;Malone & Appelqvist, 2003;Norton & Frith, 2001;Sundar, Kundu, & Kundu, 2010). Biopolymer colloidal particles can be assembled from proteins and polysaccharides using various bottom-up and top-down methods, including controlled biopolymer aggregation, segregation, and/or disruption (Aguilera & Stanley, 1999;Benichou et al, 2002;Tolstoguvoz, 2007;van der Goot & Manski, 2007).…”