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Non-communicable diseases such as diabetes, cardiovascular diseases and certain cancers are now the leading cause of death and disability, and their prevalence is rising worldwide. Poor diet is a major modifiable risk factor but changing eating habits has had limited success. Enhancing the nutritional quality of staple foods offers a complimentary intervention strategy for alleviating the burden of diet-related chronic disease. Wholegrain cereals, such as wheat, are prime targets. Their nutritional credentials and health-promoting potential are well established. Wheat is the major source of protein, minerals and vitamins, and dietary fibre for most people. Importantly, wheat is a versatile ingredient for producing foods that have high consumer appeal. Their popularity is expanding globally and small improvements in wheat grain composition conceivably translate to substantial dietary change across entire populations. A newly developed, high amylose wheat line illustrates the capacity for developing healthier processed staple food products with potential for remediating chronic disease risk. Dietary fibre density of this novel grain is markedly improved due to a >10 fold increase in resistant starch content. The sensory attributes of finished products are not compromised and preliminary studies demonstrate that consumption of the new wheat significantly improves indices of metabolic and digestive health.

It is well established that inulin-type fructans, such as oligofructose derived from chicory root, improve gastrointestinal health via fermentation and proliferation of desirable bacteria in the large bowel. However, differences in fructan structure may contribute significantly to different fermentation and subsequent metabolic effects. Here we ascertain the chain length of two novel cereal fructans (graminan) isolated from wheat stem and barley grain, and investigate their fermentation capacity in vitro , in comparison to inulin and oligofructose. Fractions, representing three predominant fructo-oligosaccharide (FOS) size ranges from each source, were fermented and short chain fatty acids (SCFA) production was measured after 24 h of batch culture. Graminan FOS when fermented produced similar levels of total SCFA as oligofructose and inulin. The fermentation of high DP FOS fractions of barley grain and wheat stem (DP 5–15) produced more propionate than oligofructose. Graminan fructans may provide a useful alternative source of oligofructose with potential additional health benefits.

Himalaya 292 is a novel hull-less barley cultivar with lower total starch content, a higher proportion of amylose and a substantially higher content of soluble and insoluble fibre. The high fibre content suggests that the grain may have potential as an ingredient in health promoting foods. In this study, 29 healthy volunteers consumed extruded whole grain breakfast cereal made from Himalaya 292 (123 g) or a commercial hull-less barley (cv Torrens) (76 g) each supplying 50 g carbohydrate. Glycemic indices were 77 ± 13 (SEM) and 50 ± 9 for Torrens and Himalaya 292 breakfast cereals respectively (P = 0.004). On this basis, the Himalaya 292 cereal is a low glycemic index food. The glycemic load (the product of glycemic index and the available carbohydrate content of a 60 g serve divided by 100) of the new cultivar was 10.1 ± 1.8 compared to 25.3 ± 4.3 for the Torrens breakfast cereal (P < 0.001). The plasma insulin response to the test meal was 26% lower for Himalaya 292 than for Torrens (P = 0.023). The data confirm that Himalaya 292 may be of value in foods designed to assist in the prevention and management of diabetes.

Some of the starch consumed by humans is not digested in the small intestine. Such starch, known as resistant starch, is fermented in the large intestine and leads to the production of short chain fatty acids. Increased consumption of resistant starch is associated with improved cardio-vascular health. A high proportion of amylose in the starch consumed is correlated with increased resistant starch but other unknown aspects of starch structure may also influence the digestibility of starch. Detailed investigation of the starch biosynthetic pathway has revealed that reducing the activity of specific isoforms of branching enzymes and starch synthases can lead to increased amylose. Methods to alter the expression of and detect mutations in targeted genes involved are discussed.