Bulk and Surface Wettability Characteristics of Probiotic Powders in Their Compressed Disc and Packed-Bed Column Forms

Abstract

Most probiotic-based products are available in powder particles under different solid-state forms. Such diversity can affect the probiotic stability, viability, and performance at different stages of processing, storage, and use. Here, we apply complementary physical chemistry techniques to characterize the bulk and surface properties of probiotic powder particles under different forms and report quantitative results of a highly concentrated multistrain reference product. The solid particle morphology, size/shape distribution, and the powder surface wettability in the compressed disc and porous packed bed forms are successively measured by sessile drop and capillary rise techniques. A complete wettability of the disc surface is observed through equilibrium contact angle measurements for various solvents, whereas the associated capillary rise data exhibit two regimes: a power law regime for the first few moments followed by a second regime, which can be described using Darcy’s law. The use of this modeling approach shows the possibility of assessing the particle-packed bed permeability and porosity. These results open a new route of the structure–activity relationship study on the impact of probiotic solid particles on their functionalities and performance in promoting health benefits, related particularly to the human and animal gut permeability. This statement also strengthens the idea of using the compressed disc technique for easily performing probiotic wettability measurements.

Rapid Ultrasound-Assisted Starch Extraction from Sago Pith Waste (SPW) for the Fabrication of Sustainable Bioplastic Film

“…Meanwhile, ultrasound-extracted starch had 51.9% size distribution of 10.5-88.9 µm and the remaining comprised of particle size ranged from 103.6-477 µm. It is important to take note that the particle size distribution data represented the size of isolated particle, minor aggregate and/or agglomerate forms [70] which supported the scenario of particle agglomeration as observed in SEM images. It is important to take note that the particle size distribution data represented the size of isolated particle, minor aggregate and/or agglomerate forms [70] which supported the scenario of particle agglomeration as observed in SEM images.…”

Wettability of Probiotic Powders: Fundamentals, Methodologies, and Applications

“…A first approach is to prepare a compact surface by compressing the probiotic powder sample under high pressure conditions for making pellets, and then measuring the liquid contact angle by the sessile drop method. This method has been used for the first time for determining the water angle contact of the cell surface of the probiotic multistrain sample [85]. Neither visible cracks nor chemical alteration has been observed before and during the measurement of the static contact angle.…”

“…Even though the capillary rise technique is by far the popular method for determining contact angles of powders or porous materials [69], it has rarely been applied to probiotic powders. Such a method has, for instance, been used for characterizing the wettability of a multistrain powder sample of probiotics, showing two regimes of the liquid penetrating rate profile [85]. The first one is a power law regime for the first few moments while the second one can be described using Darcy's law.…”

“…The first one is a power law regime for the first few moments while the second one can be described using Darcy's law. The use of this modeling approach has led to the possibility of assessing the particle-packed bed permeability and porosity through an effective radius determined by the semi-empirical Kozeny-Carman approach [85]. These physical properties are interesting for predicting some performance of probiotic strain such as product stability and cell viability during the powder storage.…”