Improving starch and fibre in wheat grain for human health

Abstract

Reducing the prevalence of diet-related diseases, including obesity and type 2 diabetes, is a major challenge for health professionals, food manufacturers and governments in both developed and developing countries. Cereals are key targets in meeting this challenge as they are staple foods throughout the world and major sources of energy (derived principally from starch) and dietary fibre. Wheat is the staple cereal in the UK and Europe, and the UK Biotechnology and Biological Sciences Research Council (BBSRC)-supported Designing Future Wheat programme is focused on manipulating the content and composition of starch and fibre to improve health impacts, including reducing the glycaemic response and improving fermentation in the colon. This work is contributing to the development of improved cultivars by breeders and foods by processors. It is also increasing our understanding of the behaviour of these components in the human gastrointestinal (GI) tract and will contribute to the establishment of targets and recommendations for regulatory authorities.

Understanding Wheat Starch Metabolism in Properties, Environmental Stress Condition, and Molecular Approaches for Value-Added Utilization

“…Wheat starch is a major storage carbohydrate and contains about 60~75% grain and 70~80% flour [3]. Starch granules located in starchy endosperm cells are composed of two polymers called amylose and amylopectin (Figure 2) [5]. Starch consists of two granules, a large A-granule (5~40 µm) and a small B-granule (<10 µm).…”

“…Recently, high amylose starch showed a positive effect on health in a study related to obesity in humans [34]. RS can generally be divided into five types [5,35]: (1) types such as seeds, legumes, and whole grains that are difficult to digest; (2) types that contain a lot of resistant starch when raw, but which disappears when ripening; (3) low resistant starch content when warm after cooking, but low in resistant starch content when cooled (higher varieties); (4) chemically manufactured starch varieties; (5) a type that combines with the type of fat to change its structure and improve digestion. Foods rich in resistant starch include oats (oatmeal flakes), cold rice, cooked legumes, cooked potatoes, and unripe bananas.…”

Gut reaction

“…Other research groups are going back to the grain itself to see whether different varieties of cereals (like wheat) can produce grains and flours with starch and fibre that foster a healthier microbiome. The Biotechnology and Biological Sciences Research Council (BBSRC) is funding the multi‐site ‘Designing Future Wheat’ programme with a focus on improving wheat quality and nutrition 6 .…”

The impact of the soluble protein fraction and kernel hardness on wheat flour starch digestibility

“…Starch is one of the most abundant sources of polysaccharides widely distributed in seeds, roots and tubers of plants, which supports about half of the carbohydrate caloric intake for much of the population of the planet (Jobling, 2004; Whistler & Daniel, 2000). Amongst starchy staple crops, one of the most widely consumed is bread wheat ( Triticum aestivum ), and understanding the factors which impact wheat starch digestion has the potential to yield nutritional benefit (Shewry, Hazard, Lovegrove, & Uauy, 2020). Starchy foods vary greatly in their digestibility in the gastrointestinal tract, and starchy foods which are rapidly digested can result in large peaks in post-prandial blood glucose concentration (Brouns et al, 2008).…”