The influence of agro-ecological conditions on technological quality of mercantile wheat

The results of the technological quality evaluation of wheat from harvests 2008 and 2010 were compared. Different climate conditions preceded the harvest in these two years. In 2008 in the region of Vojvodina June was characterized with higher temperatures and sum of rainfall under the multiannual average for this month. By the middle of June air temperatures further increased, and by the end of the month values of achieved temperatures were much higher than average. During the third decade of June air temperatures mainly ranged from 30 to 35 deg C. During May 2010 the amount of precipitation was twice above average. Rainy weather conditions remained during June with the number of rainy days three to four times higher than commonly. Therefore, wheat harvest delayed and in most localities it started in July. Differences in climate conditions resulted in very different technological quality of wheat. The main characteristic of wheat crop 2008 were reduced quality of proteins and modified quality starch component due to exposure to heat stress. The main characteristics were low and varying values of flour and dough quality parameters: Extensograph energy, Alveograph W and Amylograph peak viscosity. From raw materials of such quality bread of appropriate quality level could be produced only when special purpose additives were applied. Wheat crop 2010 was characterized by altered quality of the carbohydrate component due to extremely increased rainfall which resulted in increased content of sprouted kernels. Dough rheological properties in the case of wheat crop 2010 pointed at stable values of Farinograph parameters with quality at the level of B1 quality group. Extensograph energy, depending on the production region, varied from impossibility of determination to maximal 60 square cm. Average Extensograph ration number was under the lower limit for successful processing in bakery products. Values of Amylograph peak value are extremely varying in dependence of production region, average value is lower than optimal and related to increased amylolitic activity caused by presence of sprouted kernels. Both wheat harvests were of very uneven trade and technological quality in all wheat-growing regions of Vojvodina. Also, both crops were characterized by low values of Falling number, amylograph maximum viscosity and extensograph energy. In spite of reasonable expectations these values did not result in deterioration of wheat technological quality.