Faculty of Food Technology and Biotechnology, University of Zagreb
Abstract
The influence of mixing speed (80, 160 and 250 rpm) on dough microstructure and dough rheology has been investigated using epifluorescence light microscopy and Mixolab device. Principal component analysis was used to highlight the association between some analytical characteristics of wheat flour and Mixolab parameters during the initial kneading process (1st stage) at different mixing speeds. Significant correlations were found between the gluten deformation index and some Mixolab parameters (dough development time, work input at maximum consistency during stage 1) at all used mixing speeds. For each of the mixing speeds used, a mathematical model was developed using dough consistency and work input at different processing times (1, 2, 3, 4 and 5 min) as variables. The dough consistency and time point parameters give the best explanation of the variation of the work input, at the same mixing speeds and times.U radu je pomoću epifluorescentnog mikroskopa i uređaja Mixolab ispitan utjecaj brzine miješanja (80, 160 i 25 o/min) na mikrostrukturu i reološka svojstva tijesta. Analizom glavnih komponenata istaknuta je veza između nekih analitičkih svojstava pšeničnog brašna i parametara uređaja Mixolab tijekom prve faze miješanja tijesta pri različitim brzinama. Utvrđena je bitna korelacija između glutenskog indeksa i nekih parametara uređaja Mixolab (vrijeme dizanja tijesta i utrošak energije potreban za postizanje maksimalne konzistencije tijesta tijekom prve faze miješanja) pri svim ispitanim brzinama. Za svaku je od ispitanih brzina razvijen matematički model primjenom sljedećih varijabli: konzistencija tijesta i utrošak energije pri različitom vremenu miješanja (1, 2, 3, 4 i 5 min). Utvrđeno je da je ovisno o konzistenciji tijesta pri istim brzinama i vremenu miješanja potreban različit utrošak energije
