Physical and Cooking Properties of Analog Rice Developed from Fermented Kidney Bean Flour, Sago, and Modified Cassava Flour (Mocaf)

Analog rice has been developed as a promising alternative to traditional rice and a vehicle to fulfill public nutrition needs. The characteristics of analog rice, which is manufactured from various ingredients, greatly depend on the ingredients used and their ratio in the formulation. This study aims to analyze the physical and cooking properties of analog rice developed from fermented kidney bean flour (FKBF), sago, and modified cassava flour (Mocaf). Five formulations of analog rice were produced using extrusion technology, with a constant 20% Mocaf content and varying FKBF–sago ratios (30:50, 35:45, 40:40, 45:35, 50:30). These samples were then subjected to analyses to determine their physical and cooking properties, including their yield, bulk density, water absorption, color intensity (L*, a*, b*), cooking time, cooking weight, cooking loss, rehydration, and swelling power. No significant differences were found in the physical properties, including yield (69.83-82.58%), water absorption (96-109%), L (57.32-60.02), and a* values (1.86-3.08). However, bulk density (0.58–0.63 g/mL) and b* values (10.33–11.42) showed significant variation, with lower FKBF ratios (30:50 and 35:45) exhibiting higher bulk density and b* values (indicating a more yellow hue). For cooking properties, significant differences were observed in cooking time (8.16-10.52 mins) and swelling power (12.49-20.45%) among formulations with higher FKBF ratios (45:35 and 50:30), showing shorter cooking times and greater swelling power. In contrast, cooking weight (177.14-191.28%), cooking loss (26.8-29.13%), and rehydration (77.14-91.28%) did not differ significantly. The results revealed that the increasing FKBF ratio in the formulation likely contributed to higher yield, water absorption, cooking weight, rehydration, and swelling power, while lowering the color intensity (L* and b*), cooking time, and cooking loss of analog rice.