Refining grains removes varying proportions of the bran and germ. Because micronutrients are generally present in higher concentrations in these outer layers of the grain, refined grain products are lower in vitamins and minerals than whole grains.
The nutrient content of refined flour is determined by the ‘extraction rate’ (the proportion of the grain retained after milling). Refined flour produced in Australia is milled to an extraction rate of 78-80% resulting in a higher nutrient content (prior to fortification) than flour produced in countries using a lower extraction rate (e.g. 73-75% in the USA).
While whole grain foods may be nutritionally preferable overall, refined grain-based foods generally have a lower phytate content, which can improve mineral bioavailability, and they contribute valuable nutrients and fibre to a balanced diet. Refined grain-based foods such as white bread, white rice, corn tortillas, pasta and couscous, can be important elements in the traditional cuisines of many of the cultures represented in Australia.
Consuming up to half of all grain foods as refined core foods is not linked to increased disease risk. So while it is recommended to choose whole grain or high fibre grain foods most of the time, you can still include white rice, pasta, lower fibre breakfast cereals or white bread once a day as part of a balanced diet.
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