Shuai Bai investigates the encapsulation capacity of freeze-dried probiotic

Could you please share some details about the focus of your research? 

"Freeze drying is a very established technique used in the pharmaceutical industry, and this technique has been adopted by the probiotics industry. I have questioned using the same methods for probiotics as for pharmaceuticals, as I suspected that there are parameters that are unique to probiotics. One of these is the encapsulation ability of the freeze-dried material. The results of this study show that a significantly thicker material provides increased protection and improves storage stability for probiotics."

In what ways has your affiliation with NextBioForm contributed to both you and your research?

“Working with a large group of different experts gives you a lot of inspiration and is a great way of acquiring new knowledge and connections. The involvement in NextBioForm expands the possibilities to solve complex problems where experts in different fields can collaborate.”

You have used advanced techniques to investigate the structural properties of the freeze-dried material. Which ones?

“We combined SEM and μCT which are complementary to each other. It is only when you combine these two techniques that you can get a full picture of your material. SEM has an incredible resolution and a fast-processing time, making it possible to screen your samples and distinguish small details, but it cannot quantify the material thickness in any meaningful way.  μCT on the other hand is a time and recourses consuming technique that can provide a 3D image of your material, which you can analyze and quantify, the drawback is limitations in resolution.”

What did they help you understand?

“SEM have contributed immensely to our understanding of the characteristics of freeze-dried structures, both regarding pore-structure as well as material thickness, (and ways to alter these factors in a controlled way). We have also done synchrotron radiation X-ray micro computed tomography (SRμCT) at MAXIV in Lund. This shortens the scan time from hours to seconds which makes it possible to monitor the dynamics of freeze-drying which will be immensely valuable for the understanding and optimization of a freeze-drying process.”

What insights from your study will be useful for the probiotic supplements industry?

“The study shows the importance of the material thickness of freeze-dried pellets for the stability of the encapsulated bacteria. Primarily, the storage stability showed a strong correlation with the material thickness. This means that we found a strong correlation between increased material thickness, so-called encapsulation capacity, and increased storage stability. This makes material thickness an important parameter for the probiotics industry. Furthermore, the study shows the negative effect of oxygen on storage stability and indicates that thicker materials made of amorphous carbohydrates can hinder the transport of oxygen.”