## 3 Results and Discussion
### Viability of Encapsulated Lacticaseibacillus rhamnus GG in Simulated Gastric Conditions  
During gastric simulation, aliquots were taken at each stage to quantify the number of viable cells available. Table 3 shows the count in each stage of the in vitro simulation. The free cells had a viability of 88.2% at the end of the gastric simulation, which was smaller than the encapsulated cells that showed 97.2% and 100% for AM and UT,  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Method** & **Initial (log CFU/mL)** & **Final (log CFU/mL)** & **Viability (\%)** \\ \hline AM & 6.01 \(\pm\) 0.60 \({}^{\text{a}}\) & 5.84 \(\pm\) 0.80 \({}^{\text{a}}\) & 97.22 \\ UT & 5.71 \(\pm\) 0.07 \({}^{\text{a}}\) & 5.72 \(\pm\) 0.06 \({}^{\text{a}}\) &  
respectively. The first two phases of the simulation (salivary and gastric) failed to degrade the capsules and produce any loss of viability in these phases. Rupture of the capsules was notorious only until the last phase (intestinal stage). This behavior was described by [PERSON] et al. [38], who explained that exposure of the capsules to neutral pH and bile salts favored the ionic exchange of the alginate's carboxyl groups, leading to destabilization in the networks that form the gel, thus deforming the matrix. [PERSON] and [PERSON] [39] reported the effect that pH could have on the carboxyl group (-COOH) present in the structure of alginates that are ionically crosslinked by divalent ions such as Ca\({}^{2+}\), being insoluble at pH values of less than 4.4; and on the other hand, allowing a swelling of the matrix caused by the relaxation of these carboxyl groups at pH close to 7.4, which is ideal for formulations intended to release compounds of interest to areas ulterior to the stomach. An occurrence that also explains the modification of the capsules is syneresis, a chemical modification of the alginate caused by the variation of the pH conditions. Syneresis causes the loss of water because of the rupture of hydrogen bonds [40]. [PERSON] et al. [30] reported viability of _Lactobacillus acidophilus_ at the end of the gastric simulation of approximately 91% for their encapsulation based on alginate, and about 95.1% for their mixture with soy protein, while the free cells had a viability below 49%. All three systems had viabilities below those obtained in our study, especially comparing their alginate-based encapsulation. The probiotic survival achieved in our study is also attributed to the emulsification process that provided additional protection to the probiotic bacteria, which derived from the fatty acids present in the encapsulating mixture such as oleic acid present in Tween(r) 80, which according to [PERSON] et al. [15] provide cellular protection when they are exposed to acidic environments. The viability of _Lacticaseobacillus rhamn_s GG in this work produced good results in both encapsulated and free cells attributed to its characteristics as a bacterium with resistance to bile acids, a quality to which its prolonged survival throughout the conditions of the digestive tract can be credited [5]. [PERSON] and [PERSON] [26] suggested that sizes in the range between 1.5 mm and 2.5 mm that were obtained in their encapsulation system based on alginate result in additional protection of cells against gastrointestinal conditions caused by the increase in distance between cells and acid, thereby increasing in diffusion time. In general, the morphology and microstructure of the capsules were not affected during the first two stages of the simulation. In contrast, the capsules were deformed in the intestinal phase and lost rigidity, mainly when taking samples for microscopy analysis. To visualize the morphology of the capsules of the intestinal phase, samples were taken as in previous phases, only adding a longer drying time in the cabinet because the capsules were in a more liquid state. Still, the same visualization conditions previously described in the methodology were maintained.