Current and potential barley grain food products

Authors: Baik, Byung-Kee

Submitted to: Cereal Foods World
Publication Type: Review Article
Publication Acceptance Date: 10/17/2016
Publication Date: 10/19/2016
Citation: Baik, B.-K. 2016. Current and potential barley grain food products. Cereal Foods World. September-October 2016 61(5):188-196.

Interpretive Summary: Barley grain is mostly used for feed and its food uses constitute only a small segment of the total production. Owing to their well-documented potential health benefits largely contributed to by the relatively high content of '-glucan, however, barley grain foods are receiving unprecedented attention from food scientists, nutritionists, food manufacturers, and consumers. This article contains a description of the potential food products that could be made from barley, or into which barley could be incorporated, to increase its consumption and take full advantage of its associated health benefits, along with an extensive discussion of the associated challenges of decreased product quality and sensory acceptance, and strategies for mitigating those negative influences of barley grain incorporation. One major obstacle in achieving a more prominent food crop status for barley as a healthy and environmentally friendly food source is the relatively meager sensory quality of food products produced from or containing barley. To improve the use of barley as a food source, systematic efforts to identify the most appropriate barley grains for specific products, to apply suitable processing techniques, and to develop foods with preferred sensory qualities are needed. The goals of barley grain processing, therefore, need to be geared toward improvement of the applicability of barley in diverse food products, preparation of barley foods that are more palatable and acceptable to consumers, and development of innovative barley food products with acceptable sensory qualities. To introduce barley into the diets of consumers who are accustomed to eating wheat-based foods, manufacturers and scientists have taken the approach of partially replacing wheat flour with barley flour in the formulations of wheat-based foods such as bread, noodles, tortillas, pasta, and flatbreads. Barley flour has been added to bread, noodle, and pasta products, all of which require different degrees of gluten development, at levels ranging from 20 to 30%, without causing a reduction in processing, product, or sensory quality. Even higher proportions of barley have been used in cupcakes and cookies, which require little-to-no development of gluten. Despite the progress that has been achieved in increasing food applications for barley during the last two decades, barley-based foods are seldom found among the mainstream foods we eat daily. The development of a signature barley food product that consumers will readily eat in daily meals might be the first goal toward which barley scientists need to work to make barley a staple food crop. The information concisely described in this review will help food manufacturers identify the potential target barley foods and guide them to select the appropriate barley grain types for the production of specific food products with minimal negative influences on product quality, resulting in an increased number of available barley foods, which can be readily accepted by consumers who will then be able to take full advantage of barley’s associated health benefits.

Technical Abstract: Barley has been an important food source from the beginning of human civilization, and remains an important staple food crop in a few countries, although its consumption has decreased sharply with the ample availability of more palatable and versatile food crops such as rice and wheat. In many Western countries, barley is used mainly for feed and malt, and food use constitutes <2% of total production. Interest in incorporating barley in the diet has grown recently, however, as diet-related human health issues including type 2 diabetes, overweight and obesity, high blood pressure, coronary heart disease, and certain cancers have become more widespread, especially in developed countries. Barley, along with oats, is a rich source of soluble dietary fiber, especially ß-glucan. The role of ß-glucan in lowering blood cholesterol levels, which can benefit heart health, and in controlling weight gain is well-documented. Barley also is rich in many phytochemicals, including phenolics, phytates, and tocols, whose bioactivity can reduce oxidative degenerative reactions in the human body. A major challenge in the preparation of barley foods, especially when using barley to replace wheat in traditional wheat-based products, is the dilution of gluten brought about by the addition of barley flour. Barley flour has been successfully added to wheat flour in various proportions to make leavened breads, noodles and pasta without a significant reduction in product quality and sensory characteristics by the selection of wheat flour of high and strong protein, the adoption of a sponge and dough baking process and the use of ascorbic acid and xylanase for volume improvement. For the production of noodles, it is necessary to select a proanthocyanidin-free type and an appropriate starch amylose content of barley for minimal development of dark gray color and desirable textural attributes for each type of noodles, respectively. Barley alone or its blend with wheat flour can be easily used for the preparation of flatbreads and tortillas with few processing challenges and little product quality reduction, since extensive gluten development and formation of bubbles during dough mixing and fermentation are not required. The use of pearled and/or proanthocyanidin-free barley up to 30% in a blend with wheat flour is known to produce flatbreads and tortillas with bright color, desirable rolling properties and a low degree of breakability. Barley would be better suited for making cookies, cakes and muffins with minimal or no requirement for gluten development than for making leavened breads. The relatively higher water absorption of barley flour, mainly caused by ß-glucan, is, however, a hurdle in utilizing barley flour for the production of soft wheat baked products with low moisture contents, such as cookies and crackers. Barley flour may be better suited for use in moist products such as chemically leavened breads, muffins, and pancakes, for which a high water absorption capacity is of less concern.