## 3 Results and Discussion  
### Viability Rate of Lacticaseibacillus rhamnus After Spray Drying and During Powder Storage  
Adding oil and other hydrophobic substances to the microcapsules is an effective method of protecting the lactic acid bacteria. [PERSON] et al. [28] have shown that the viability of bacteria in the soybean oil matrix is higher than that of free microorganisms [28]. [PERSON] et al. [37] spray-dried _Lactobacillus bulgaricus_ using a mixture of gum Arabic, gelatin, and coconut oil in various concentrations as protective substances. The content of individual components of the protective composition was at different levels: gum Arabic between 30-40%, gelatin at 20-25%, and coconut oil at 40-55%. The highest percentage of viability after spray drying was observed when gum Arabic and gelatin reached the maximum limit and coconut oil the minimum limit in the feed composition [37]. The most frequently used liquid oils are fish oil, sunflower oil, and soybean oil. [PERSON] et al. [27] have shown that the presence of tuna oil (15 g, 6% w/v) increases the viability of _Lacticaseibacillus casei_. They obtained 37.62% and 56.19% bacterial cell viability without and with tuna oil, respectively [27]. In our study, specially prepared emulsions with the addition of various liquid oils (in two concentrations) were spray-dried to obtain microencapsulated LGG bacteria in the form of dry powders. We showed that the addition of oils (regardless of their contentin the emulsion) increased the viability of bacteria both during the spray drying process and during storage for 4 weeks at 4 \({}^{\circ}\)C and 20 \({}^{\circ}\)C (\(\pm 1\)\({}^{\circ}\)C). In all samples, the number of probiotics before spray drying was approximately at a level of 10\({}^{9}\) CFU/mL. The results of performed tests are shown in Figure 1A-D.  
Figure 1: _Cont._  
The viability rate of LGG after spray drying in the control sample was only about 13% of the starting concentration. In the case of 20% oil content, the highest percentage  
Figure 1: The effect of the concentration of various oils on the viability of LGG bacteria after the spray-drying and during the storage of various encapsulation systems (**A**) 20% of oils stored at 4 \({}^{\circ}\)C (**B**) 20% of oils stored at room temperature (**C**) 30% of oils stored at 4 \({}^{\circ}\)C (**D**) 30% of oils at room temperature. Values with different uppercase letters in the same column are significantly different at \(p<0.05\). Values with different lowercase letters in the same column are significantly different at \(p<0.05\). The statistical analyses were performed using Statistic version 10 StatSoft Poland, (Krakow, Poland). of bacterial cells that survived the drying process was observed when forage oil (83.69%) was added as a protective material, and the lowest when milk thistle oil (37.91%) was added (Figure 1A or Figure 1B). At a higher oil concentration of 30%, the best result was also obtained for forage oil (86.03%), where at the same time the lowest viability among all tested oils was observed for nigella oil (58.49%) (Figure 1C or Figure 1D). The above results show that the viability of bacteria after the drying process in the case of using each oil, regardless of its concentration, differed significantly from the control sample (\(p<0.05\)) (Figure 1A-D). The viability rate of the probiotic bacteria in final dry powders was determined after storage at 4 \({}^{\circ}\)C and 20 \({}^{\circ}\)C (\(\pm 1\)\({}^{\circ}\)C) for 4 weeks. Higher bacterial viability was noted when the powder was stored in refrigeration conditions (regardless of the concentration of added oils) (Figure 1A-D). After 4 weeks of storage of the reference sample, at a temperature of 4 \({}^{\circ}\)C 6.57% of live bacteria remained, while respectively at room temperature only 1.80%. Regardless of the type and concentration of protective substance, in each case, a better result was obtained during storage in refrigerated conditions (Figure 1A-D).