Abstract:

The stabilization of waxy millet bran from Chongqing was conducted by microwave heating. The effects of millet
bran moisture content, microwave power and radiation time on acid value after 6-week storage were explored using an
orthogonal array design to optimize the three factors. The results indicated that a microwave power of 600 W and a radiation
time of 90 s were found to be optimal for the stabilization of a 1 cm thick layer of waxy millet bran with 27% moisture
content. After 6 weeks of storage at 37 ℃, the resulting product showed an acid value of 21.40 mg KOH/g, far lower than
that of the control group (171.00 mg KOH/g). The optimal conditions for degreasing waxy millet bran determined by
response surface methodology were 59 ℃, 17 min, 1:2.5 (g/mL) and 60 W for temperature, time, solid-to-liquid ratio and
ultrasonic power, respectively. Under these conditions, the degreasing rate of waxy millet bran was 90.89%.

Key words: millet bran, stabilization, degreasing, optimization