Abstract:
Probiotics are microorganisms that offer a wide array of health benefits to the consumer,
thus its extensive applications in the food industry. Recent innovations in probiotic food
science include the formulation of Lactiplantibacillus-supplemented functional food. In
functional food development, optimizing process conditions to maintain probiotic
efficiency while minimizing economic costs are of central importance. Currently, the
optimization of the freeze-drying procedure of Lactiplantibacillus plantarum BS25, a
novel lactic acid bacteria strain isolated in the Philippines, is yet to be explored. On this
basis, the optimization of L. plantarum BS25 freeze-drying time and cryoprotectant
inulin concentration was done. The Central Composite Design was used to establish the
experimental design with 13 points. Freeze-drying yield and storage viability data
obtained from experimental runs with different levels of the process variables were
subjected to response surface methodology. Freeze-drying time has a significant
quadratic effect on freeze-drying yield, and significant quadratic and linear effects on
storage viability. Meanwhile, inulin concentration has a significant quadratic effect for
both freeze-drying yield and storage viability. Optimal values of the process variables
that result in a desirability of 0.949 were determined: (1) freeze-drying time of 6.793
hours and (2) inulin concentration of 0.763 % (w/v). Such process conditions result in a
freeze-drying yield and storage viability of 91.58% and 70.41%, respectively.
Optimization of other parameters involved in the lyophilization of L. plantarum BS25
should be done in future studies for the successful application of the novel strain as a
probiotic. The findings of this study provide information on the application of RSM for the optimization of the freeze-drying procedure of L. plantarum BS25, a novel LAB
strain, to maximize its industrial potential.
