NERICA-8 brown rice: its pasting properties, nutrients and bioactive compounds as affected by milling, germination temperature and germination time

Abstract

Effects of milling, germination temperature and time on pasting properties, nutrients and bioactive compounds of NERICA-8 brown rice (UBR) were investigated. Germinated brown rice (GBR) samples were obtained by germinating UBR at 30℃ and 40℃ for 12 and 36 h. Pasting properties, bioactive compounds and nutrients of GBR, UBR and milled rice (UMR) were analyzed and compared. Results showed that setback, trough, final and peak viscosities of UBR reduced significantly (p<0.05) in GBR while breakdown viscosity increased. Antioxidant activity (1.20 µg.ml-1), γ-amino butyric acid (GABA) (1.85 mg.100g-1), protein (10.99%), total dietary fiber (8.20%), vitamins and minerals (mg.100g-1) including iron (4.65), zinc (1.70), calcium (106.00), vitamin B2 (1.66), vitamin E (1.38) contents of UBR increased in GBR up to 355.83%, 329.73%, 28.03%, 9.63%, 113.98%, 17.65%, 74.53%, 110.24%, and 41.30%, respectively at 36 h germination. Milling reduced the levels of these compounds. Total starch, total carbohydrate and amylose contents of GBR decreased as germination time increased. Proteins, amino acids and magnesium were significantly (p<0.05) increased at germination temperature of 30℃ than 40℃ while dietary fiber, vitamin E and GABA were higher at 40℃. Germination time of 36 h and temperature of 40℃ were recommended due to optimum contents of the bioactive compounds.