Impact of acidity, hardness and iron content of cooking water on bulgur quality

The two main raw materials used in making bulgur are wheat and water. In bulgur factories, different water sources are used as water source and the chemical constituents of water affect various properties of bulgur produced. The aim of this study is to use cooking water in bulgur production after adjusting its chemical properties and to examine the quality parameters after cooking (cooked wheat) and drying, tempering, bran separation, grinding operations (bulgur) and to contribute to the production of better quality bulgur. In order to achieve this, pH (3, 5, 7, 9 and 11), hardness (~53 (soft), 129 (hard) and 269 (very hard) mg/L CaCO3) and iron contents (0, 1 and 2 ppm) of the wheat cooking water were adjusted and used in the bulgur production. In the study, some properties of water and wheat were examined during cooking. Wheat, cooked wheat and bulgur samples underwent analyses for pH, moisture, ash, protein, fat, starch, colour, phenolic compounds, antioxidant activity, mineral content and texture profile. Furthermore, FTIR and DSC analyses were performed on wheat and bulgur samples and additional sensory analysis was performed on bulgur samples. As a result of the study, it was determined that the colour of bulgur darkened in bulgur produced with cooking water with a pH ≥11 and that cooking with very hard water negatively affected the colour of bulgur, but the amount of iron did not have a negative effect on the colour. The results of the study showed that the textural properties of bulgur were not statistically significantly affected by the acidity, hardness and iron level (P>0.05) of cooking water.