Adding barley may enhance antioxidant, vitamin E content of bread

January 27, 2016

A study published in the Journal of Food Science shows that replacing a portion of the standard baking flour with barley flour may enhance the total antioxidant and vitamin E content of pita bread.

Barley is typically polished (also known as pearling) before consumption because whitened grain is generally preferred by consumers and food manufacturers. The process of pearling removes the hull (also known as the husk) and the bran, both of which are rich in antioxidant capacity and vitamin E. Hulless barley does not require pearling and is preferred in food production as less processing is required. In addition, the grain contains more protein, starch, and total soluble fiber, and can be added directly to food. Malt made from hulless barley is of particular interest because of these same advantages.

The barley varieties used in this study (the hulless genotype Finniss and the covered genotypes WI2585 and Harrington) were previously identified as being high in antioxidant capacity and vitamin E content. Grain from each variety was used immediately after harvest to make flour, either from whole grains (0% pearling), or with 10%, 15%, or 20% pearling. Flour was also prepared from malt prepared from Finniss and after storage at 10°C for 4 months.

The researchers made pita bread from either 100% baker’s flour (control) or 50% malt flour, whole-grain flour, or flour from barley grains pearled at 10%, 15%, and 20% grain weight. Antioxidant capacity and vitamin E content of flours and pitas were determined by their ability to scavenge 2,2-diphenyl-1-picrylhydrazyl radicals and high performance liquid chromatography, respectively. The physical and sensory properties of the pitas were also assessed.

The researchers found that the pitas made from either whole grain or pearled barley flour had a higher antioxidant capacity and most also had higher vitamin E content than standard pita. The antioxidant and vitamin E levels were reduced in pearled compared to whole grains, but the extent of that reduction varied among genotypes. The greatest antioxidant and vitamin E levels were found in pita made from malt flour or Finniss whole grain flour. Furthermore, sensory analysis suggested these pitas were acceptable to consumers and retained similar physical and sensory properties to those in the control pita.