부산대학교 도서관

Microencapsulation of probiotics is an efficient way that can improve the viability rate of them in dairy products like yogurt as well as in lumen tract conditions. The viability of free and microencapsulated forms of Lactobacillus rhamnosus and Lactobacillus acidophilus were evaluated in yogurt and under simulated gastrointestinal conditions. Microencapsulation and double coating process carried out by alginate-chitosan and Eudragit S100 nanoparticles and by the extrusion method. Bacterial count (cfu g-1) of L. acidophilus reduced from 7.0x108 to 4.2x106 in day 0 and in day 42 in yogurt containing free bacteria, while the bacterial count of microencapsulated bacterium showed a reduction from 3.3x107 to 2.5x107. Microencapsulation of L. rhamnosus could also increase the viability of this bacterium; 3.2x109 to 5.8x106 bacterial count by reduction of free-form storage, and 7.6x109 to 3.4x108 bacterial count by reduction of microencapsulated form in 42 days. On day 14 (first day of bacterial count in gastrointestinal condition) L. acidophilus count was 1.3x10³ and 5.0x107 which reached 2.0x100 and 2.8x104 on day 42 in free and microencapsulated forms respectively. The bacterial count of L. rhamnosus decreased from 1.2x10³ to 5.0x100 in free form, and from 2.5x107 to 2.8x104 in microencapsulated one. The results of this study suggest that this method of microencapsulation can improve the viability of L. rhamnosus and L. acidophilus in yogurt and in the simulated human gastrointestinal tract. [ABSTRACT FROM AUTHOR]