Expanding opportunities for barley food and feed through product innovation

Barley has a long history of use as both human and animal food and is grown in many countries around the world. In Western countries, barley is primarily used for animal feed and for malting and brewing with very little designated for food use. Over the last two decades there have been a number of important developments that have influenced or have the potential to influence barley utilization in food and feed.

Interest in the use of barley as a food grain has increased primarily because of its reported health benefits. Barley is an excellent source of β-glucan soluble fibre and contains antioxidants, vitamins, minerals, and phytonutrients such as phenolics and lignans. These components have biological activities that can reduce the risk of coronary heart disease, diabetes and certain cancers. As a whole grain, barley can also play a role in weight maintenance. One key development which will have a significant effect on the use of barley as a food ingredient in North America is the pending FDA health claim for coronary heart disease and β-glucan soluble fibre from barley.

Another important development that has the potential to influence the use of barley in food applications is the development of hulless barley cultivars and varieties with low amylose (waxy), zero amylose and high amylose content. Hulless cultivars permit greater ease in milling and pearling with enhanced processing yields and have higher levels of β-glucan. Waxy cultivars typically have higher β-glucan levels than non-waxy types. Although high levels of β-glucan are undesirable in animal feed and malting and brewing applications, it can be advantageous in the development of barley based foods by providing improved functionality and nutritional properties. Thus, the development of a wide range of barley types allows for targeting specific barley cultivars to specific end uses.

Application of novel technologies to isolate and concentrate β-glucan to maintain molecular structure and solubility has resulted in commercialization of barley β-glucan preparations for use in the food industry. In addition, the application of infrared technology has shown the potential to yield whole barley food products with unique end-properties.

In terms of animal feed, barley has the potential to continue to be one of the preferred cereals in beef, dairy and swine rations in Western Canada. Until the late 1990’s barley was only used to a limited extent in poultry rations due to the negative effects associated with the viscous soluble fibre, β-glucan, on bird performance. However since that time, an endogenous enzyme, β-glucanase, has been developed that effectively eliminates the anti-nutritional effects associated with β-glucan. This enzyme is now commercially available and it is common practice to use barley in poultry rations when the cost is competitive with other cereals. However, the use of enzymes to reduce the negative impacts of the soluble fibre in cultivars specifically designed for food use which contain exceptionally high levels of soluble β-glucan may not be sufficient thereby reducing the utility of this ingredient in poultry diets unless regular types of barley are used.

One factor that has limited the use of barley in poultry and some swine rations is the high proportion of insoluble fibre from the hull attached to the seed. As a result, hulless barley cultivars have the potential to markedly increase energy content if used as a feed ingredient. Although the development of hulless cultivars could significantly impact the utilization of barley in feed rations both domestically and internationally, there have been difficulties in establishing a market for hulless barley. The primary issue has been the inability to obtain a premium for the product that offsets the reduced yield caused by loss of hulls during harvesting. If this issue can be addressed, hulless barley has the potential to develop into an important market in both feed and food.

Another new possibility which has the potential to increase the use of barley in feed applications is the development of a new type of barley which may reduce phosphorus levels in animal feces. The majority of phosphorus in plants is found in a form that animals are not able to digest. As a result, the diets are supplemented with available inorganic phosphorus and the undigested organic fraction is passed into the feces which can result in environmental issues where intensive livestock production occurs. Although these low phytate cultivars are not currently available on a commercial basis, if they are released for production, they will likely be an attractive feed ingredient given the pressure to reduce the impact of livestock production on the environment.

Although barley is a very popular ingredient in ruminant rations, the starch is susceptible to rapid fermentation in the rumen resulting in digestive disorders if the product is not handled correctly. In addition, rapidly fermented starch can cause depression in milk fat content which is undesirable given the current incentive to increase milk fat content of milk. The recent development of the barley cultivar Valier shows significantly reduced rates of starch fermentation suggesting a possible improvement in the utility of barley as a feed ingredient.

Barley, like all other feed ingredients has inherent variability and this affects the value and the utility of the product. Prior studies have demonstrated the potential to determine nutritional value of barley using Near Infrared Reflectance Spectroscopy (NIRS) but the calibrations were not developed to the extent that they could be used commercially. Recently, a consortium of researchers and industry partners in Canada have initiated a program to develop a commercially useful NIRS calibration so the nutritional profile of individual lots of barley could be rapidly established prior to use. Once this calibration is available in approximately 3 years, both the producers and the end users will have the ability to segregate, value and use the barley based on its’ actual value further improving the utilization and value of this important feed grain. Additionally, this technique has the potential to be used to confirm the identity of varieties of grains with unique characteristics increasing the likely hood that novel barley will be identifiable and utilized by the feed industry. It is also possible that this initiative will be useful to the food industry to target selected barley qualities to specific end use applications.

Thus, the use of barley as a food and feed ingredient shows tremendous potential for the future. Development of hulless and novel types of barley with unique characteristics as well as the application of novel technologies has and will continue to have a significant effect on the expansion of barley utilization. Efforts to increase the use of barley need to continue and success can be achieved through innovations made at the breeding, processing and product development level.

By L. Malcolmson, R. Newkirk and G. Carson - Canadian International Grains Institute, Winnipeg, Manitoba
^{(Presented at the North American Barley Researchers Workshop, July 17-20, 2005)}
Published at the Government of Alberta Agriculture and Rural Development website