## 2 Materials and Methods
### Chemical Analysis  
#### 2.3.1 Nutritional Profile  
The nutritional profile of the biju bread was analyzed following the official AOAC methodology [9] unless otherwise stated.  
Moisture: The moisture content was analyzed following AOAC method 925.09 [9], in which 2 g of the sample was placed in a metal dish that was closed and weighed. The dish was placed in an oven (Scientific Series, Contherm, Lower Hutt, New Zealand) at 100 \({}^{\circ}\)C for five hours, and after cooling down, it was weighed again. The moisture was calculated by subtracting the final weight from the initial one.  
Crude protein: Protein content was calculated using the Macro-Kjeldahl method, following the AOAC 920.87 method [9], using a conversion factor of 5.8. Briefly, 0.5 g of samples were digested in a K\({}_{2}\)SO\({}_{4}\)/CuSO\({}_{4}\) catalyst and sulphuric acid at 400 \({}^{\circ}\)C for three h. Then, an integrated alkaline stead distillation and titration took place in a [PERSON] distiller (model Pro-Nitro-A, JP Selecta, Barcelona, Spain). The crude proteins were expressed as g/100 g of fresh weight (fw).  
Crude fat: A Soxhlet apparatus was used to extract and quantify the crude fat, using 3 g of a sample and petroleum ether as an extracting medium. Crude fat was expressed as g/100 g of fresh weight.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Chemical Composition** & **DW** & **TW** & **BMW** \\ \hline Calcium (Ca) & 9.8 & 23 & 102 \\ Magnesium (Mg) & \textless{}1.0 & 5.0 & 24 \\ Silica (SiO\({}_{2}\)) & - & 70 & 62 \\ Nitrate (NO\({}_{3}\)) & \textless{}2.0 & \textless{}0.30 & \textless{}0.25 \\ Sodium (Na) & 2.8 & 511 & 577 \\ Potassium (K) & \textless{}1- & 56 & 28 \\ Lithium (Li) & \textless{}0.1 & 2.3 & 1.9 \\ Iron (Fe) & \textless{}0.05 & 0.23 & \textless{}0.01 \\ Manganese (Mn) & \textless{}0.015 & 0.05 & 0.20 \\ Lead (Pb) & \textless{}0.003 & \textless{}0.003 & \textless{}0.003 \\ Cadmium (Cd) & \textless{}0.0005 & \textless{}0.0004 & \textless{}0.0004 \\ Aluminum (Al) & 0.032 & \textless{}0.003 & 0.021 \\ Copper (Cu) & \textless{}0.020 & \textless{}0.002 & \textless{}0.002 \\ Chromium (Cr) & \textless{}0.002 & \textless{}0.001 & 0.0022 \\ Nickel (Ni) & \textless{}0.005 & \textless{}0.005 & \textless{}0.005 \\ Selenium (Se) & \textless{}0.0005 & \textless{}0.0004 & \textless{}0.0004 \\ Arsenic (As) & \textless{}0.00059 & 0.119 & 0.0011 \\ Zinc (Zn) & - & \textless{}0.05 & 0.0028 \\ \hline Total & 12.63 & 667.70 & 795.13 \\ \hline BMW had higher levels of Ca (102 mg/L), Mg (24 mg/L), Na (577 mg/L), Mn (0.20 mg/L), and Cr (0.0022 mg/L) compared to DW and TW. On the other hand, TW had higher levels of silica (70 mg/L), potassium (56 mg/L), lithium (2.3 mg/L), iron (0.23 mg/L), and arsenic (0.119 mg/L) than DW and BMW. & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Mineral composition (mg/L) of drinking water (DW), thermal water (TW), and bottled mineral water (BMW).  
Ash: Ash content was calculated following the AOAC 923.03 [9], in which 0.5 g of the sample was incinerated in a muffle (Lenton ECF 12/22, Hope Valley, UK) at 550 \({}^{\circ}\)C. The ash content was expressed as g/100 g of fresh weight.  
Total carbohydrates were calculated by difference. The energy value was calculated using the European Parliament and Council Regulation No. 1169/2011 [10]. Energy (Kcal/100 g fw) = 4 \(\times\) (g crude protein + g total carbohydrates) + 9 \(\times\) (g crude fat).