Iron fortification and parboiled rice quality: appearance, cooking quality and sensory attributes

BACKGROUND: Iron (Fe) fortification of parboiled rice increases both Fe concentration and bioavailability in milled grains (i.e. white rice). The aim of the present study was to evaluate parboiled rice fortified with 250 and 450 mg Fe kg(-1) paddy rice for its pre-cooking appearance, cooking quality, basic sensory attributes and overall acceptance in comparison with unfortified parboiled rice in Thailand and local parboiled rice in Bangladesh. RESULTS: Fe fortification at 250 mg Fe kg(-1) paddy rice significantly elevated Fe concentration in white rice to as high as 19.1 mg Fe kg(-1) white rice, compared with 6.2 mg Fe kg(-1) white rice for unfortified parboiled rice, without any adverse impact on consumer acceptance based on the current preliminary assessment. The added Fe was well retained in the cooked rice, with significant residual value for human intake. Panellists in Thailand and Bangladesh did not detect significant differences in the acceptability of parboiled rice fortified at 250 mg Fe kg(-1) paddy rice compared with unfortified and local parboiled rice respectively. However, Fe fortification of parboiled rice at the higher level of 450 mg Fe kg(-1) paddy rice significantly intensified the yellow colour of the grain and changed the off-flavour, chewiness and flakiness of the cooked Fe-fortified parboiled rice. This resulted in a low acceptability ranking of parboiled rice fortified at 450 mg Fe kg(-1) paddy rice by panellists in both Thailand and Bangladesh. CONCLUSION: Fe fortification of parboiled rice at an appropriate level (e.g. 250 mg Fe kg(-1) paddy rice) is dosage-effective and acceptable to rice consumers. Consumer acceptability of Fe-fortified parboiled rice is closely related to pre-cooking appearance, cooking quality and sensory attributes. (C) 2009 Society of Chemical Industry