THE EFFECT OF THE ADDITION OF VARIOUS TYPES OF OILS ON THE TECHNOLOGICAL QUALITY OF WHEAT DOUGH AND BREAD

Abstract

The aim of this work was to evaluate the effect of the addition (0.5 %, 1 % and 1.5 %) of vegetable oils (pumpkin, rapeseed and sunflower oil) on the technological quality (rheological properties of dough, bakery indicators and bakery experiment) of wheat dough and subsequently wheat bread. The wheat flour type T 650 was used as a base and also control. In this type was determined a dry matter of 86.65 %. By determining the bakery indicators (crude protein content, falling number, starch content, ash content, titratable acidity and Zeleny index) it is possible to summarize that this type of four was strong.  The gluten properties of T 650 flour were optimal and suitable for bakery use. The specific volume, volume yield, bulk productivity, bread yield, loss during baking and shape were determined by a baking experiment. The highest specific volume was determined in a bread loaf with the addition of 1.5 % pumpkin oil – 424.2 cm³.100 g^-1. The volume of prepared breads increased with oil addition – the highest value was determined in sample with the addition of 1.5 % sunflower oil (volume increase of 24 % with compared to the control variant without addition. The shape of prepared breads was optimal; the bulk productivity increased in direct proportion to the addition of individual oils. The addition of vegetable oils had a beneficial effect on the rheological properties of the dough. The farinograph properties were good, but in the wheat dough with the addition of rapeseed oil, the development time of the dough gradually decreased. After the addition of pumpkin oil, it was determined development time of the dough (the difference between the maximum and minimum) higher by 55 % with compared to the control variant without addition. It was also recorded positive results for the evaluation by the extenzograph properties. By a comprehensive evaluation, it can be stated that the addition of vegetable oils had positive effects on wheat dough and prepared bread.