Peanut milk was prepared as previously described (Salunkhe and
Kadam, 1989) with minor modifications. The seeds were sorted to
remove discolored grains and any foreign material. Selected peanut
seeds were roasted at 130 °C for 20 min in a forced air circulation
oven. The seeds were peeled and weighed before being soaked in
0.5 g/100 mL NaHCO3 for at least 12 h. The shelled seeds were then
washed with running water and mixed with distilled water in a ratio
of 1:5 [peanuts (g):water (mL)] and transferred to a stainless steel
blender (Cemaf, São Paulo, Brazil) for 5 min. The resulting paste was filtered
through a double-layered cheese cloth.
For the soymilk preparation, 250 g of selected beans was initially
soaked in 1 L of distilled water for 16 h at 25 °C. Subsequently, 190 g
of these moistened beans was soaked in 500 mL water in a stainless
steel blender and mixed for 3 min. Then, the resulting slurry was
filtered through double-layered cheese cloth and boiled for 5 min
(Champagne et al., 2009).
The peanut and soybean milk were mixed in the 2:1–peanut milk:
soymilk ratio. The heat treatment was carried out by pasteurization at
90 °C/20 min, followed by immediate cooling to 4 °C.