## 3 Results and Discussion
### Bocaiiva Powder-Pulp Characterization
As expected, the addition of inulin and/or bocaiiva powder-pulp increased the soluble solid content of the kefir-fermented soymilk from ~2.3 \({}^{\circ}\)Brix for the CONT to ~5.3 \({}^{\circ}\)Brix for IN3.5, ~2.8 and ~3.4 \({}^{\circ}\)Brix for BO3.5 and BO7.0, respectively, and ~9.3 \({}^{\circ}\)Brix for BO + IN. Osmolality showed no significant difference during the storage of the CONT (~225.6 mOsmol/kg), BO3.5 (~279.3 mOsmol/kg), BO7.0 (~248.1 mOsmol/kg), and BO + IN (~292.3 mOsmol/kg) beverages. In contrast, for the IN3.5 beverage, the osmolality increased until day 11 (from 292.4 to 333.8 mOsmol/kg) and remained high until day 16 (337.4 mOsmol/kg). Based on the definitions of the European Food Safety Authority (EFSA) [55], we classified the beverage as hypotonic (<270 mOsmol/kg) before supplementation and isotonic (270-330 mOsmol/kg) after supplementation with inulin and/or bocaiiva powder-pulp (or both). Isotonic beverages can help preserve the body's hydration by being in equilibrium with body fluids and preserving water absorption [56]. Figure 2 shows the syneresis of kefir-fermented soymilk with and without inulin and/or bocaiiva powder-pulp supplementation. Syneresis data showed no significant difference in syneresis during the storage of CONT (~90.2%), BO3.5 (~71%), BO7.0 (~62.1%), \begin{table}
\begin{tabular}{l c} \hline \hline
**Analysis** & **Content** \\ \hline Moisture (g/100 g) & 6.22 \(\pm\) 0.30 \\ Ash (g/100 g) & 3.15 \(\pm\) 0.06 \\ Protein (g/100 g) & 2.94 \(\pm\) 0.30 \\ Lipids (g/100 g) & 9.15 \(\pm\) 0.35 \\ Carbohydrate & 78.54 \(\pm\) 0.25 \\ Energy & 408.27 \(\pm\) 0.20 \\ pH & 5.57 \(\pm\) 0.03 \\ Soluble solids (\({}^{\circ}\)Brix) & 3.10 \(\pm\) 0.15 \\ Acidity (mg/mL) & 0.24 \(\pm\) 0.01 \\ \hline L* parameter & 53.24 \(\pm\) 2.48 \\ a* parameter & 14.09 \(\pm\) 1.14 \\ b* parameter & 39.20\(\pm\) 2.03 \\ Chroma & 37.97 \(\pm\) 2.32 \\ Hue & 71.31 \(\pm\) 0.89 \\ Vitamin C content (mg/100 g) & 13.12 \(\pm\) 8.66 \\ Total carotenoids (\(\mu\)g/g) & 6.34 \(\pm\) 1.50 \\ Total phenolic compounds (g/100 g) & 216.58 \(\pm\) 7.12 \\ Antioxidant activity using DPPH method (\(\mu\)M TEAC/100 g) & 10.69 \(\pm\) 0.003 \\ Antioxidant activity using ABTS method (\(\mu\)M TEAC/100 g) & 557.00 \(\pm\) 36.56 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Proximate composition and properties of _Accornia aculeata_ (Jacq.) Lodd. powder-pulp. and BO + IN (~57%). In the IN3.5 beverage, there was no change in syneresis until day 11 (~75.3%), and then there was an increase on day 16 of storage to ~93.5%. Figure 1: The pH **(A)**, acidity **(B)**, soluble solid content **(C)**, and osmolality **(D)** of kefir-fermented soymilk beverages supplemented with inulin and/or bocaiiva powder-pulp at 1 (black bar), 6 (dots), 11 (gray), and 16 (white) days. CONT, without adding ingredients; IN3.5, with the addition of 3.5% inulin (\(m/v\)); BO7.0, with the addition of 7.0% bocaiiva powder-pulp (\(m/v\)); and BO + IN, with the addition of 3.5% inulin + 3.5% bocaiiva powder-pulp. Different letters indicate a statistical difference between the fermented beverages during the shelf life by the Tukey test (\(p<0.05\)). Figure 2: Syneresis (%) of kefir-fermented soymilk supplemented with inulin and/or bocaiiva powder-pulp at 1 (black bar), 6 (dots), 11 (gray), and 16 (white) days of shelf storage. CONT, without adding ingredients; IN3.5, with the addition of 3.5% inulin (\(m/v\)); BO3.5, with the addition of 3.5% inocaiva powder-pulp (\(m/v\)); BO7.0, with the addition of 7.0% bocaiiva powder-pulp (\(m/v\)); and BO + IN, addition of 3.5% inulin + 3.5% bocaiiva powder-pulp. Different letters indicate a statistical difference between the fermented beverages during the shelf life by the Tukey test (\(p<0.05\)).