Oat beta-glucan: health benefits and quantification methods

Beta-glucans are linear polysaccharides composed of glucopyranose units linked by β-(1,3) and β-(1,4) linkages found in cereals. These polysaccharides are known to be associated with various health benefits, including the reduction of blood cholesterol levels, postprandial glucose peak and body weight. In recent years, increasing interest in the health benefits of beta-glucans, together with recommendations for their daily intake, has led to the development of various analytical methods for quantifying beta-glucan content in oats and oat-based products, including enzymatic assays, dye-binding assays, high-performance liquid chromatography, and viscosity measurements. These analytical methods present advantages and significant limitations. For instance, the enzymatic assay developed by Megazyme is a widely used and highly accurate method; however, it is a time-consuming and high-cost method. In contrast, near-infrared reflectance spectroscopy combined with chemometrics can be a fast, nondestructive, and cost-effective method, but it requires further development for effective utilization in food industries and plant breeding programs. Given the health benefits of beta-glucans and the diverse industrial applications of oat grains, the development of a robust analytical method for accurate quantification of the content of beta-glucans is crucial. This review provides literature updates on the association between oat beta-glucans and blood cholesterol levels, postprandial blood glucose levels, blood pressure, body weight and cancer risk. In addition, this review also provides insight into the nature, advantages and disadvantages of current analytical methods used for quantifying beta-glucan content in oats.