2. Materials and Methods
2.1. Production of pre-gelatinized rice and black bean flours
The peeled bean grains were obtained by soaking in hot water (40ºC) during 4 hours and drying at
80ºC in the oven during 3 hours, approximately. A soya bean dehuller was applied for mechanical peeling
of bean. The samples were then milled using a knife and hammer mill until it reached the granulometry of
40 mesh. Mixtures of rice and peeled black bean (70:30) or whole black bean (60:40) were extruded on
INBRAMAQ RX-50 extruder in order to produce pre-gelatinized flour (PBF and WBF respectively).
Priscila Z. Bassinello et al. / Procedia Food Science 1 (2011) 1645 – 1652 1647
The extrusion parameters were set using temperatures between 120 and 125ºC; mixture moisture
during processing set at 13.58% (WBF) and 16% (PBF); motor rotation speed set at 378 rpm; feeding rate
of 33g/minute and circular matrix of 4mm.