Microencapsulation of probiotic cells

The ingestion of viable probiotic cells is associated with various well-documented health benefits, generated by providing a positive impact on the ecosystem in the human intestinal tract (Jia et al., 2008; Naidu et al., 1999; Tamime, 2005). Thus, the addition of living probiotic microorganisms to mostly fermented foods is a frequent strategy to meet the increasing demand for healthy “functional foods” (Rodgers, 2008; Stanton et al., 2001). The WHO recommends a description of probiotics as “live microorganisms which, when administered in adequate numbers, confer a health benefit on the host” (Ross et al., 2005). Therefore, maintenance of the viability and functionality of the probiotics until they reach their site of colonization in the human gut is one of the key requirements for an effective application (Mattila-Sandholm et al., 2002; Ross et al., 2005). However, a decline ofbioactivity, that is the loss of living probiotic cell numbers during processing, storage, and gastrointestinal transit has been found to be crucial for successful and effective application in functional foods (Mattila-Sandholm et al., 2002; Shah, 2000; Siuta-Cruce and Goulet, 2001). In this regard, the delivery of probiotic cells in microencapsulated form offers a promising way to enhance the survival of these sensitive bacteria by reducing the impact of detrimental factors from the outside environment, and hence protecting the cells against adverse external conditions (Augustin, 2003; Champagne et al., 2005; Ross et al., 2005).