Bioactive ingredients encapsulation

This chapter considers the issues relating to the delivery of bioactives through foods. The choice of materials for encapsulation of bioactives, the formulation of the encapsulated delivery system and the processes used for their manufacture are discussed. Examples of materials and processes used for the manufacture of encapsulated fat-soluble and water-soluble bioactives and encapsulated probiotics are given. The effectiveness of various encapsulated delivery systems for protection of bioactive ingredients and new trends in encapsulation technology are covered. The... 

Spray drying is the most commonly used method in the food industry. Bioactive ingredients microencapsulated by this method include fats and oils, flavours, essential oils and other oil-soluble bioactives. Water-soluble bioactives can also be encapsulated by spray drying, where the encapsulant forms a matrix structure rather than a film surrounding the core. This process typically involves the dispersion of the core material into a solution of the encapsulant (e.g., protein, carbohydrate) and atomization of the mixture into the drying chamber. This leads to evaporation of the solvent... 

In summary, it can be concluded that it is possible to produce peptides from P-lactoglobulin through enzymatic hydrolysis, which keep the encapsulation properties of p-lactoglobulin, but significantly reduce autoxidation of the encapsulated bioactive ingredient (Fig. 2.18). It is well documented for liquid emulsions that... 

In the spray-dried particles, microencapsulation efficiency was increased in bilayer emulsions (Fig. 2.23) and when using low-methoxylated pectin, oxidative stability of the encapsulated bioactive ingredient was decreased (Fig. 2.24). The process-induced shift in the oil droplet size was more pronounced in bilayer emulsions based on high methoxylated pectin than in bilayer emulsions based on low-methoxlyated pectin (Fig. 2.25). However, both emulsions were more stable than the protein-stabilised emulsions. Data from dilatational rheology show an... 

Microencapsulation technology has been traditionally used in the food industry for flavour encapsulation where flavours are stabilized and their release controlled (Madene et al. 2006). Microencapsulation has also been used to enable the incorporation of sensitive bioactive component in fortified foods, while ensuring that the taste, aroma, or texture of food is not adversely affected (Pszczola 1998 Brazel 1999 Augustin et al. 2001). Microencapsulation can reduce off-flavours contributed by certain vitamins and minerals, permit time-release of the nutrients, enhance stability to extremes in temperature and moisture, and reduce undesirable chemical interactions with other ingredients. 

Encapsulated delivery systems are developed with a specific purpose for each target application. To date, most research has been directed at stabilizing extracted bioactives and delivering the required levels in food. Their ultimate delivery to a target site depends on the core, the material and the methods used for encapsulation as well as the food vehicle used for delivery. Although there have been many technological advances there are still limitations to the use of microencapsulated ingredients in some applications. 

The characterization of the particles in terms of size and shape is essential and has a direct impact on the behavior of this particulate system. These data may be correlated with encapsulation efficiency, the form of release of the active ingredient from the matrix, and the efficiency in protecting the bioactive. 

Bioencapsulation is a technology, being used since three decades, which uses bioactive molecules to be inserted and immobilized on specific supports (matrices). Encapsulation technology is now well developed and accepted within the pharmaceutical, chemical, cosmetic, foods, and printing industries. The encapsulation of active components has become very attractive being adequate for food ingredients as well as for chanicals, drugs, or cosmetics to be released in a controlled way. 

The bioactive substance that is encapsulated is called the core material, active ingredient or agent, or internal phase. The material encapsulating the core is referred to be a matrix, as support material, coating, shell, or wall material. 

The encapsulation of bioactive compounds represents an efficient approach of wide use in the food and nutraceutical industry to promote homogeneous dispersion of bioactive compounds in the end product, to protect them from interaction with other ingredients and from degradation during end product transformation, storage, and preparation, as well as to control their release where needed. 

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