In the bustling world of food technology, a quiet revolution is brewing, one that could significantly impact the way we store and preserve essential bacterial cultures. Researchers from the Key Laboratory of Dairy Biotechnology and Engineering at Inner Mongolia Agricultural University have made a groundbreaking discovery that could redefine the future of starter cultures in the food industry. Led by Hui Qiao, the team has uncovered a novel approach to enhance the freeze-drying and storage resistance of Lacticaseibacillus paracasei, a bacterium widely used in the production of fermented foods.
Freeze-drying is a common method for preserving starter cultures, but it often leads to cell instability and reduced viability over time. This poses a significant challenge for the food industry, where the consistency and quality of starter cultures are crucial. The research, published in the npj Science of Food, explores a unique solution to this problem by focusing on the adenine methylation ability of Lacticaseibacillus paracasei.
The team created a mutant strain of Lacticaseibacillus paracasei Zhang that lacks adenine-specific DNA-methyltransferase, effectively removing its ability to methylate adenine. This unmethylated mutant was then subjected to freeze-drying and stored at 30°C for periods of 30 and 60 days. The results were striking. The unmethylated mutant demonstrated superior cell viability and survival rates compared to the wild-type strain. “The unmethylated mutant not only survived the freeze-drying process better but also maintained its viability over extended storage periods,” Qiao explained.
The study delved into the metabolic pathways of the stored mutant and wild-type bacteria, revealing significant differences. These differences were consistent across transcriptomic, proteomic, and metabolomic analyses, highlighting key metabolic pathways such as the phosphotransferase system, carbohydrate and amino acid metabolism, and fatty acid biosynthesis. By modulating these pathways, the researchers were able to enhance the bacteria’s resilience to freeze-drying and storage conditions.
The implications of this research are far-reaching. For the food industry, this discovery could lead to more stable and reliable starter cultures, reducing waste and improving the consistency of fermented products. “This research opens up new avenues for developing more robust starter cultures that can withstand the rigors of industrial processing and storage,” Qiao noted.
Beyond the immediate applications, this study contributes to the broader understanding of bacterial adenine methylation and its role in industrial strain applications. As the food industry continues to evolve, the need for more resilient and efficient starter cultures will only grow. This research provides a foundation for future developments in this area, paving the way for innovations that could revolutionize the way we produce and preserve fermented foods.
The findings, published in the npj Science of Food, which translates to English as ‘npj Food Science’, mark a significant step forward in the field of food biotechnology. As we look to the future, the work of Qiao and her team offers a glimpse into a world where bacterial cultures are more resilient, more reliable, and better equipped to meet the demands of modern food production. The journey from lab to market is long, but the potential benefits are immense, promising a future where our food is not only delicious but also more sustainable and consistent.