DisplayTitle

Predicting Baking Performance from Rheological and Adhesive Properties of Rye Meal Suspensions During Heating

¹Department of Food Technology, Kaunas University of Technology, Radvilenu pl. 19, 3028 Kaunas, Lithuania. ²Department of Food Technology, Center for Chemistry and Chemical Engineering, University of Lund, P.O. Box 124, S-221 00 Lund, Sweden. ³Corresponding author. Phone: +46 46 222 9674. Fax: +46 46 222 9517. E-mail: Ann-Charlotte.Eliasson@livsteki.lth.se ⁴Svalöf Weibull AB, S-268 81 Svalöv, Sweden.

Rheological methods were used to study the behavior of rye meal suspensions during a time-temperature treatment corresponding to the initial baking conditions (<70°C). Eight different rye cultivars were investigated, with four of the cultivars grown during two different years. Baking experiments included pan bread and hearth bread. Viscosity, falling number, and the amount of adhesive material present during heating were measured. The storage (G′) and loss (G″) moduli increased during a temperature sweep from 45°C, reaching a maximum at 62.1–67.1°C. At the same time, the amount of adhesive material increased. A further increase in temperature caused a decrease in G′ and G″, whereas the amount of adhesive material continued to increase. The mechanical spectra (G′ or G″ vs. frequency) showed that the rye meal suspensions had gel-like behavior at 45°C which turned into behavior typical of a strong gel at 70°C. The rye meals performing the best in hearth bread baking gave intermediate values of G′ and G″ and high values of the phase shift (δ) at 45°C. During the temperature sweep, the G′ values of these rye meal suspensions increased slowly to a maximum of 62.1–67.1°C.