1- Department of Soil Science, College of Agriculture, Shiraz University, Shiraz, Islamic Republic of Iran.
Abstract: (6263 Views)
Consumption of whole-wheat breads prepared from high extraction flours is recommended because of their high content of fiber, vitamins, and minerals. Despite the beneficial effects of these breads, they contain high amounts of undesirable compounds like Phytic Acid (PA) which is believed to negatively interfere with the absorption of some such nutrients as zinc (Zn). Wheat genotypes are different in their PA and Zn concentrations; therefore, cereal-based foods may be prepared using grains of low PA and high Zn. Fars Province is ranked first in Iran in terms of wheat production. It is, therefore, important to evaluate the PA and Zn status of the wheat cultivars common in the province. Seventeen wheat cultivars obtained from Genotype Improvement Department of Fars Agricultural Research Center, Zarghan, Iran were employed in the study. These cultivars that are commonly used by local farmers were grown in test plots under identical conditions. A wheat grain sample from Parvardeh Wheat Milling Factory and 7 bread flour samples from Shiraz city's bakeries were also included in the study. The PA content and phytase activity of the grains either with or without bran as well as those of the flour samples were determined. Results showed that the method of grain debranning significantly affectted the concentration of PA and phytase activity. The least phytic acid was found in Pavarus and Niknejad cultivars. The PA to Zn molar ratios were highest in Falat, Niknejad and Shiraz cultivars. The highest concentration of Zn was observed in Estar, Falat, and Niknejad, while maximum phytase activity was found in cultivars Estar, S-78-11, S-79-10, and Niknejad.
Received: 2011/04/21 | Accepted: 2011/04/21 | Published: 2011/04/21