*4.3.1 Food applications*

For probiotic-based food products and ingredients used in the preparation of fermented foods and diet supplements, the degree of wetting needs to be at the right value for ensuring both good preparation during the hydration and high stability during the storage. Some examples of commercialized products are listed in **Table 2**. Probiotic powders are currently formulated with a mixture of components, including mono- or multistrain microorganisms and other active and functional ingredients and excipients (e.g. prebiotics, antioxidants, cryoprotectors, anti-agglomerates, diluents, lubricant, colorant, binder, coating agent, sweetening agent, anti-caking agent, binders, etc.) (**Table 3**). Binders are, for instance, adhesives that provide the cohesiveness essential for the bonding of solid particles during the process of agglomeration [88]. Consequently, their wettability is an important criterion for the powder dispersibility when rehydrate or reconstituted, and powder stability related to porosity during the storage. This also impacts the viability of probiotic strains, which are sensitive to the environmental conditions such as humidity and temperature.

The wettability of probiotic powders may vary as a function of other components within their formulations. When the latter contain prebiotics, mainly carbohydratebased compounds, the products are called synbiotics. It has been demonstrated that prebiotics can change the probiotic surface properties, and therefore would impact the wettability of whole products [89]. It is also well known that free fats in the surface reduce wettability whereas some surface-active agents, especially those exhibiting dispersing capacity commonly improve wettability in dried containing fat products [88].

*Wettability of Probiotic Powders: Fundamentals, Methodologies, and Applications DOI: http://dx.doi.org/10.5772/intechopen.106403*


#### **Table 2.**

*Some examples of commercialized products of probiotic powders.*


#### **Table 3.**

*Some excipients in probiotic powder formulations.*

#### *4.3.2 Agricultural applications*

Agricultural applications of probiotic powders include animal and plant health and growth, as illustrated with some examples in **Table 4**. Probiotics have been recognized to be benefits to the host animal as feed supplements and animal products (e.g. poultry, ruminant, pig, and aquaculture) in improving food safety. Their use aims at reducing, even substituting antibiotics to control pathogens in poultry production [90].

For probiotic-based agriproducts such as microbial feed supplements, pesticides, and anti-weeds, an optimum powder wettability is required for ensuring high dispersibility in the liquid media preparation, but also for maximizing the spreading and penetrating properties with regards to the target materials (e.g. plant leaves).

In aquaculture, probiotic activities mainly result from the production of antimicrobial metabolites and the attachment or adhesion to intestinal mucus for competing with pathogens.


#### **Table 4.**

*Applications of probiotic powders in agriculture (adapted from [39]).*

Plant health benefits and growths in using probiotics involve direct mechanisms through beneficial microbes-host plant interactions, including adherence and colonization steps, or indirect ones due to the antagonistic activity against plant pathogens. Probiotic plant antagonism includes inhibition, competition for nutrients, and degradation of pathogenicity factors [91].
