Viabilitas Bakteri Asam Laktat dalam Enkapsulasi Sinbiotik terhadap Penyimpanan dan Asam Lambung Tiruan

Abstract

Probiotics are living microorganisms that provide health benefits to the host. Probiotics in the form of free-cells may decrease cell viability against environmental influences. This study aimed to get the lactic acid bacteria as probiotic potential candidate and encapsulated materials which are able to maintain cell viability during storage and in simulated gastric juice. The four isolates of lactic acid bacteria were examined using antagonist tested against Escherichia coli, Staphylococcus aureus and Salmonella typhimurium. Potential isolate obtained was AK2 with the greatest inhibition diameter 15.60 mm, 16.09 mm and 8.12 mm. AK2 has been encapsulated with 3 type materials namely alginate (AL), alginate-skim milk-inulin (ALSI) and alginate-soy flour-inulin (ALTI) by extrusion method. Characterization of synbiotic was performed by cell viability test of probiotic capsules at two different temperatures; 4 oC and 27 oC for 4 weeks of storage. Total population of bacteria after 4 weeks of storage was relatively stable at 7-10 log CFU mL-1 in all three types of capsules. Survival of free-cell and encapsulated cell against simulated gastric juice has been performed with various pH; 2, 3 and 6 for 2 hours. Free-cell and AL capsule were unable to maintain cell viability at pH 2 for 2 hours by decreasing 27.92% and 34.31% respectively while ALSI and ALTI capsules were able to maintain cell viability by reduction value of 12.70% and 9.44% respectively. Encapsulation double-layer of lactic acid bacteria and prebiotic by alginate-skim milk and alginate-soy flour were able to maintain the viability cell during storage and in simulated gastric juice.