Abstract:

In order to determine the optimum conditions for producing iron-biofortified germinated brown rice, the effect
of rice varieties, iron nutrition fortifiers, iron concentration, soaking temperature soaking time, germination temperature, and
germination time on the contents of organic iron and γ-aminobutyric acid (GABA) were investigated. Results showed that
the contents of organic iron and GABA were significantly increased in the “Lühan No. 1” cultivar of germinated brown rice
after being treated with 0.005 mol/L FeSO4. The optimal conditions for iron biofortification of brown rice during germination
were obtained as follows: iron concentration, 0.005 mol/L; soaking temperature, 30 ℃; soaking time, 10 h; germination
temperature, 32 ℃; and germination time, 44 h. Under these conditions, the content of organic iron was (405.48 ± 9.18) mg/kg,
a 51-fold increase over that of ordinary germinated brown rice. The majority of organic iron in the germinated brown rice
was bound to proteins, accounting for 53.74% of the total iron. The GABA content was (508.04 ± 13.50) mg/kg, which was
14 times higher than that of ordinary germinated brown rice.

Key words: brown rice, germination, organic iron, γ-aminobutyric acid