分離自土壤、植物、發酵乳產品、動物或人類糞便中的乳酸菌，是一種具有治療及保健效果的益生菌；目前益生菌乾燥粉末的製造技術，常利用冷凍乾燥或噴霧乾燥將益生菌製成產品，然而在乾燥的過程中，菌株的存活率不佳將使益生菌的效果降低。本研究的目的即在於找尋益生菌微膠囊的保護配方，使益生菌在冷凍乾燥後仍能達高劑量的存活菌數。本研究設計乃以3%海藻膠添加3%脫脂奶粉及2%蛋白腖包埋 L. rhamnosus GG 以製備成微膠囊（A-MsP），最後測試微膠囊化製程對益生菌在冷凍乾燥時的保護效果。
實驗結果顯示，A-MsP 的微膠囊化配方可使益生菌在冷凍乾燥後的存活菌數達 1011 CFU/g 以上，且 L. rhamnosus GG 經微膠囊化後可提升其在胃酸環境下的存活菌數，而微膠囊化後的乳酸菌在腸道環境下亦可順利自微膠囊中釋出；但是，未來若要應用在噴霧乾燥的製程上則需要再改良微膠囊的配方；此外，A-MsP 的微膠囊化配方在低溫儲存六週後仍可維持乳酸菌的活性。未來，此益生菌微膠囊將可應用在發酵乳產品、健康食品或作為一個藥物傳輸系統使用的潛力。
Lactic acid bacteria isolated from soil, plants, fermented dairy products, animal feces or human feces are considered to be probiotics with therapeutic and healthy properties; however, the effectiveness of probiotics can be affected by manufacturing processes, such as freeze-drying or spray-drying. The purpose of this study was to develop a technique for microencapsulation of probiotics that can protect probiotics during the freeze-drying process. The formulations(A-MsP) of alginate (3%) with 3% skim milk powder, and 2% peptone were prepared. The effect of the cryoprotectants on cell survival during freeze-drying was investigated using a standardized amount of cells and the optimized freeze drying media.
The results showed that this formulation (A-MsP) provided sufficient protection for probiotics, resulting in probiotic counts of up to 1011 CFU/g after freeze-drying. The survival of microencapsulated L. rhamnosus was better than free cell at low pH. The release of encapsulated cells in simulated aqueous solution of colonic pH was also assessed. However, this formulation (A-MsP) needs to be improved if we want to apply microencapsulation to spray-dry. The microencapsulated lactic acid bacteria maintain their survival at 4℃ during a 6 week period. This probiotic microencapsule can potentially be used in fermented dairy products and healthy food products or as a drug delivery system in the future.
