Preparation of Saccharomyces boulardii powder by spray drying: thermoprotectants optimization and stability evaluation

Abstract

Saccharomyces boulardii as the probiotic yeast was widely used in the pharmaceutical, feed and food industries. The influence of skim milk, gelatin, and carbohydrates on the heat resistance of S. boulardii is explored in the article. Response surface methodology was effectively applied to optimize the thermoprotectant composition for S. boulardii during spray-drying. The accelerated test is applied to evaluate its the subsequent storage stability. The results show that the thermoprotectants composition was comprehensively optimized such as: 15.12% skim milk, 1.81% gelatin, and 9.73% trehalose. The highest viability was 17.77%, which was basically the same as the predicted value of 18.21%. The inactivation rate constant of spray-dried powder was k_-18 = 1.04 × 10⁻⁵ h⁻¹, the quantity of viable cells stored at this temperature for 1 and 10 years was 8.25 × 10⁸ CFU/g and 1.25 × 10⁸ CFU/g, separately. This work provides a thermoprotectants formula for the S. boulardii during the spray drying process.

Keywords:

• Box–Behnken design
• probiotics
• Saccharomyces boulardii
• storage stability
• thermoprotectant

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was supported by Key Special Project of "Technology Boosts Economy 2020," National Nature Science Foundation of China [32101908], Key R&D Projects in Shaanxi Province [No. 2020NY-185 and 2020KW-031], Science and Technology Project of Yulin [No. CXY-2020-088], the Science and Technology Project of Xianyang City [Grant No. 2017k02-24], and Technology Project of Weiyang District, Xi'an City [No. 201941].