ABSTRACT:The aim of the present paper was to evaluate the influence of different climatic conditions on the activity of alpha-amylase in wheat samples and bread quality parameters. Three wheat varieties grown in three different localities in three years were chosen for this study. Commonly used methods for estimation of alpha-amylase activity in wheat grain were employed. The obtained results indicated that harvest year 2013, which was characterized with the excessive amount of rainfall, exhibited the highest level of alpha-amylase activity and the lowest values of the peak viscosity. The lowest alpha-amylase level and the highest peak viscosity and FN value were observed for samples harvested in 2012 which was characterized with the greatest number of days with an average daily temperature above 30 and 35 °C. In addition, a decrease in Mixolab parameter torque C3 and specific bread loaf volume, as well as increase in the breakdown torque (C3-C4) of samples harvested in 2013 were observed, which could be attributed to rainy weather influencing increase in alpha-amylase activity. It is found that specific bread loaf volume of wheat samples is highest in 2012. Moreover, a negative correlation between alpha-amylase activity and specific bread volume for all the samples grown in three years was determined.

The wheat flour represents a complex system whose quality is influenced by several factors such as genotype, growing conditions and the complex interaction of genetic and environmental factors. In recent years, wheat quality fluctuation has become a major issue for millers and bakers. Requirements of bakery industry for providing wheat flour of uniform quality impose the need for further investigation in direction of monitoring/improving wheat flour quality. Therefore, the objective of the present study was to evaluate wheat varieties, grown in different locations, by breadmaking potential and proteolytic activity in dependence of climate conditions. Wheat flour of four wheat varieties (Pobeda, Zvezdana, Gordana and Apache), from seven locations in Serbia characterized by different climatic conditions in two production years, were used in this study. The analyses included a determination of proteolytic activity and the rheological properties of dough. Rheological properties of wheat flour dough were determined by Gluten index and Brabender equipment (Farinograph, Extensograph and Amylograph). The studies ended with a trial baking and estimation of textural properties of obtained bread. Large variability for all attributes evaluated was observed, with wider ranges in quality parameters across varieties than among growing locations. Wheat flour samples from 2012 production year were characterized by inferior quality parameters. Proteolytic activity and bread specific volume values for 2012 production year were significantly lower compared to 2011. These results indicate that level of proteolytic activity was under optimum for obtaining bread with higher specific volume.

ABSTRACT:This work was focused on the performance of trained and untrained panel in evaluating the texture of nine commercially produced wheat spaghetti. Several sensory methods were applied in order to investigate the performance of different panel groups. In order to avoid the loss of information obtained by non-parametric methods, data were scaled according to contingency tables. This analysis showed that significant differences existed between the two panels for the given products. On the basis of these results, it can be concluded that the used panels cannot be a good alternative to each other in providing sensory texture profiling of commercial spaghetti, except in the case when the properties of spaghetti were evaluated using the control sample.