Effect of milling and temperature of germination on nutrients, bioactive compounds and pasting properties of FARO 44, FARO 57 and NERICA-8 brown rice cultivars

Abstract

Germinated brown rice (GBR) was produced from FARO 44, FARO 57 and NERICA-8 cultivars by de-husking the paddies and germinating them at 30°C and 40°C for 24 h. Bioactive compounds, nutritional composition and pasting properties were analysed and compared to that of non-germinated parboiled milled rice (MR) and non-germinated brown rice (BR) from the same cultivars. The results showed that germination improved the bioactive compounds and nutrients. Protein, ash, total dietary fibre, calcium, iron, zinc, selenium, vitamins B2 and E, DPPH and gamma amino butyric acid (GABA) contents of BR increased significantly (p<0.05) in GBR but decreased significantly in MR. Total carbohydrates and total starch contents of BR decreased significantly in GBR. The increase in protein, total dietary fibre, vitamin E, DPPH and GABA contents of GBR were by 6.28-45.31%, 3.09-15.80%, 113.68-153.85%, 38.00-410.00% and 159.46-288.11%, respectively depending on the cultivar and the germination temperature. Increase in germination temperature from 30°C to 40°C resulted in significant increase in iron, zinc, GABA, total phelolic, total flavonoid contents, and all the pasting viscosities but it decreased the magnesium, protein and amino acid contents significantly. FARO 57 possessed improved bioactive compounds and nutrients than the other rice cultivars.