Dietary Fiber Characteristics and Mineral Availability from Treated and Non-Treated Brown Rice

Abstract

Background: Brown rice has greater mineral content than milled rice. However, due to high dietary fiber and phytic acid content, mineral absorption may be suppressed. Objective: To determine the dietary fiber characteristics and mineral availability from treated and non-treated brown rice. Materials and Methods: Four varieties of cooked brown rice were used in the study and the same treated to extend the shelf-life of brown rice. Freeze-dried samples were analysed for proximate composition, dietary fiber, phytic acid, iron, zinc and calcium content using standard methods. Mineral availability and dietary fiber fermentation were determined in vitro. Results: The dietary fiber content of treated brown rice (11.0±0.6 – 11.7±0.1) was significantly greater than that of non-treated brown rice (5.5±0.5 -6.4±0.2; P<0.05). The mineral content and availability from treated and non-treated brown rice did not differ significantly except for mineral availability. Dietary fiber and phytic acid did not show inhibitory effect on mineral availability from both brown rices. The dietary fiber content from both brown rices was fermentable producing short chain fatty acids with greater amounts of propionate. Conclusion: Treated and non-treated brown rice are good sources of minerals and dietary fiber, found to be fermentable, and did not inhibit mineral availability.