Influence of cereal grain non-starch polysaccharides such as beta-glucan and arabinoxylan in their native and hydrolysed forms on starch amylolysis

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Humans evolved in the context of eating whole grain foods. Our body is designed to consume and digest starchy cereal grains that contain a variety of Non Starch Polysaccharides (NSPs) (i.e. components of dietary fibre), phytates, phenolics, etc. that confer health benefits. However, in modern times, highly refined cereal ingredients such as white wheat flour, polished rice, pearled barley, etc. are used substantially in food processing as ingredients. These refined ingredients are highly depleted in NSPs, phenolics, phytates, etc and are used in processed grain foods to improve flour functionality and facilitate high volume processing, as well as to improve the food's sensory characteristics (eg: softer, whiter baked goods or finer textured pastries). More recently, as society has become more concerned about how a refined diet can affect health negatively, it now demands a return to more nutritious and whole grain foods. The dilemma presented to the food industry is that although NSPs in whole grain foods have health benefits, they negatively impact the high volume food processing and especially the sensory qualities to which consumers have grown accustomed. In order to mitigate these negative effects of NSPs, microbial based crude enzyme preparations (eg: xylanase, beta-glucanase, etc) are often added, primarily for the purpose of hydrolyzing NSPs. This is largely an empirical, "black box" process, in which the molecular details are not well understood. We know that these crude enzymes improve food sensory attributes and processing capabilities by producing hydrolyzed dietary fibre. However, the impact of NSPs on human health is not clear, especially how those partially hydrolysed NSPs affect amylolysis. The objective of the proposed research is to develop a better understanding of how some NSPs, in their native and hydrolysed form, would influence starch amylolysis. The results of this study is expected to show how NSPs would be beneficial to the Canadian food industry and the general public at large for intelligent management of health issues around starch digestion, obesity, type II diabetes, and general human health.