Effect of temperature and post-harvest storage duration on flour quality and dough rheological properties of bread wheat (Triticum aestivum L.) cultivars

Management of storage conditions can affect bread wheat grain quality that may lead to improvement of flour qualityand balancing rheological properties of dough. Therefore, controlling the storage conditions as well as the storage duration of bread wheat grain has a significant role in the flour quality and rheological properties of dough. The aim of this study was to investigate the effect of storage temperature (25 °C and 45 °C) and post-harvest storage duration (0, 30, 60 and 90 days after harvest), on flour quality characteristics, enzymatic and rheological properties of e dough of five bread wheat cultivars (Mehregan, Chamran2, Sirvan, Sardari and Azar2). The experiment was conducted as factorial arrangements in completely randomized design with three replications at the Seed and Plant Improvement Institute, Kraj, Iran, in 2018. The results showed that flour protein content and pH decreased with increasing storage temperature and duration, while acidity and falling number increased. On the other hand, by increasing storage duration up to 60 days after harvest at 25 °C and storage duration up to 30 days at 45 °C, wet gluten, Zeleny sedimentation volume and SDS sedimentation height increased in all bread wheat cultivars, and then decreased. The results of evaluation of farinographic properties of dough of bread wheat cultivars showed thatwater absorption increased with increasing storage temperature and duration. Also at 45 and 25 °C the development time, stability time and valorimetric value of dough increased over time up to 30 and 60 days, respectively, and then the value of parameters decreased. Whereas the degree of dough softening decreased at 25 °C and 45°C over the storage duration until the 30 and 60 days after harvest, and then increased. In conclusion, considering the results of this experiment, for optimizing flour quality and rhological properties of dough produced from grains of the five studied bread wheat cultivars, it is recommended that grain is stored at at 45 °C for 30 days and at at 25 °C for 60 days after harvest..