Parametric Study on the Viability of Freeze Dried Lactobacillus plantarum BS as Starter Culture for Cream Cheese Production
Author : Yap, Judith Asada
Major Adviser : Arocena, Rhebner E.
Major Co-Adviser : Mercado, Susana M.
Committee Members : Movillon, Jovita A.; Valencia, Jeanne Michelle T.
Year : 2016
Month : December
Type : Thesis
This manuscript can be accessed: Only after the consultation with author or adviser
This study focused on the incorporation of freeze-dried Lactobacillus plantarum BS in cream cheese. The effects of inoculum size, inoculation temperature and salt concentration on the viability of the L. plantarum BS cells in cream cheese were determined using a two level factorial experimental design. Lactobacillus plantarum BS was grown in cheese whey and soy bean meal extract and was freeze-dried to prolong its shelf life. Freeze-dried cells was reactivated prior to inoculation. From the analysis of variance, increasing the inoculum size increased the viability L. plantarum BS cells while decreasing the inoculation temperature decreased the same response. The salt concentration and all the interaction effects were not significant to the response. The best parameter combination (10% v/v inoculum size, 30°C inoculation temperature and 0.5% w/v salt concentration) that gave the highest viability was used to construct a time profile of pH, TTA and VCC in cream cheese. After 24 hours, viability increased exponentially from 10⁶ to 10⁹. TTA and pH were unstable which could be accounted from instrumental inaccuracies and bacterial adaptations. TTA and pH were fluctuating within 0.5 to 1.2% and 5.00 to 5.33 respectively.
Go back to Research Abstracts