Biotechnological aspects of using whey in the bakery technology
The aim of the work is to study the biotechnological properties of whey in bakery technology, exemplified with rye-wheat bread. The author propose the use of milk whey to prepare rye-wheat flour instead of yeast. To reduce the α-amylase activity, the rye-wheat flour is put in the whey for 4 hours. The evaluation of the acidity of the rye-wheat dough, treated with whey, shows the titratable acidity to increase from 7 to 8.4 degrees, and the active acidity is equal to 6.3. Amylases are known to react differently to acid media. When increasing the acidity of the medium, α-amylase completely deactivates at pH 3,3 and at the same time β-amylase keeps its activity approximately at 80 %. The moisture content in the analyzed samples remaines practically on the same level. The dough porosity increases along with increasing concentration of the milk whey in the dough kneading. When adding whey, gasification processes in the pre-dough and dough significantly intensify. In a tight pre-dough, gasification increases on average by 8 %, in a less tight pre-dough - by 9 %, in the dough prepared from these pre-doughs the gasification increases by 15 and 20 %, respectively. The dough with whey addition becomes ready 30 min earlier than the one without whey. When whey is the formula of products, it should noted: the use of whey leads to an increase of the elevating power of starter cultures, a duration reduction of fermentation and proofing, a decrease of viscosity and elasticity of the dough; whey is to be dosed only in the pre-dough or only in the dough