Baking Time (baking + time)

Distribution by Scientific Domains


Selected Abstracts


Optimisation of hard pretzel production

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2007
Ni Yao
Summary Absence of a thorough understanding of the baking conditions on hard pretzel quality has resulted in considerable loss of production and on productivity. Baking time, oven zone 1 temperature, drying time and kiln drying temperature were identified as important factors affecting pretzel quality in modern pretzel production, from a total of eleven factors following a screening experiment design. A central composite circumscribe design was then employed to optimise these four variables. The test for lack of fit was not significant (P < 0.05) for the responses, except for colour a* values. The analysis of variance of the responses indicated that models explained 99%, 91% and 87% variability for moisture content, ,Eab and pasting time, respectively. The four variables were optimised when pretzel moisture content, ,Eab and pasting time were considered simultaneously using desirability function approach. Validation experiment results revealed that the two most important qualities of pretzel, moisture content and ,Eab could be reliably predicted. [source]


IDENTIFICATION OF IMPORTANT PRODUCTION VARIABLES AFFECTING HARD PRETZEL QUALITY

JOURNAL OF FOOD QUALITY, Issue 3 2005
N. YAO
ABSTRACT The objective of this study was to determine the importance of raw material and processing variables that influence pretzel quality by utilizing a screening experiment design. Eleven variables were selected based on preliminary experiments, and a two-level-11-factor (211) fractional factorial experimental design was used to screen the variables. Several responses were measured for dough before and after extrusion, for half-baked and fully baked pretzels. These responses are important indicators of consistency and quality during pretzel processing. Results indicated that flour protein content, the amount of water added to make dough and dough mixing time were important variables influencing dough behavior. Caustic concentration affected brightness of half-baked pretzels but did not influence the color of the final product. Baking time was the most important factor for both half-baked product and final product qualities. The hardness of fully baked pretzels was influenced by baking time, temperature in baking oven zone 1, drying time and drying temperature. The color of final products was significantly influenced by baking time, while both baking time and drying temperature affected the moisture content of the final product. A key observation was that none of the raw material or dough processing parameters, within the range tested, influenced final pretzel quality as defined by pretzel moisture content, hardness or color. [source]


A NUMERICAL APPROACH WITH VARIABLE TEMPERATURE BOUNDARY CONDITIONS TO DETERMINE THE EFFECTIVE HEAT TRANSFER COEFFICIENT VALUES DURING BAKING OF COOKIES

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2006
EREN DEMIRKOL
ABSTRACT The increasing trade of ready-to-eat foods such as cookies highlights an interest in quality defects during baking. Heat (h and thermal diffusivity) and mass (mass transfer and diffusion coefficients) transfer parameters are significant parameters affecting the quality changes. Therefore, it is important to determine these parameters for modeling and process optimization studies. Among these, the h is important, revealing the relationship between the heating medium and product surface. As baking involves a simultaneous heat and mass transfer involving moisture diffusion and heat conduction inside and convective heat and mass transfer outside, a lumped system method may not be an accurate choice to determine the h value. Changes in the product volume and contact heating from bottom of the product also bring extra challenges to the determination of h. Therefore, the objective of this study was to use realistic approaches including simultaneous heat and mass transfer to determine the changes in h. The heffvalues for the bottom and top surface of the cookies were then determined, applying a numerical procedure where the surface temperature changes were the boundary conditions with evaporation on the surface. The hband ht values increased with baking temperature and varied with baking time. The results of this study showed that evaporative mass flux for the top surface, heat flux for the bottom surface and the product's volume changes were significant in the variation of h values. [source]


IDENTIFICATION OF IMPORTANT PRODUCTION VARIABLES AFFECTING HARD PRETZEL QUALITY

JOURNAL OF FOOD QUALITY, Issue 3 2005
N. YAO
ABSTRACT The objective of this study was to determine the importance of raw material and processing variables that influence pretzel quality by utilizing a screening experiment design. Eleven variables were selected based on preliminary experiments, and a two-level-11-factor (211) fractional factorial experimental design was used to screen the variables. Several responses were measured for dough before and after extrusion, for half-baked and fully baked pretzels. These responses are important indicators of consistency and quality during pretzel processing. Results indicated that flour protein content, the amount of water added to make dough and dough mixing time were important variables influencing dough behavior. Caustic concentration affected brightness of half-baked pretzels but did not influence the color of the final product. Baking time was the most important factor for both half-baked product and final product qualities. The hardness of fully baked pretzels was influenced by baking time, temperature in baking oven zone 1, drying time and drying temperature. The color of final products was significantly influenced by baking time, while both baking time and drying temperature affected the moisture content of the final product. A key observation was that none of the raw material or dough processing parameters, within the range tested, influenced final pretzel quality as defined by pretzel moisture content, hardness or color. [source]


Optimal Predictions in Everyday Cognition: The Wisdom of Individuals or Crowds?

COGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 7 2008
Michael C. Mozer
Abstract Griffiths and Tenenbaum (2006) asked individuals to make predictions about the duration or extent of everyday events (e.g., cake baking times), and reported that predictions were optimal, employing Bayesian inference based on veridical prior distributions. Although the predictions conformed strikingly to statistics of the world, they reflect averages over many individuals. On the conjecture that the accuracy of the group response is chiefly a consequence of aggregating across individuals, we constructed simple, heuristic approximations to the Bayesian model premised on the hypothesis that individuals have access merely to a sample of k instances drawn from the relevant distribution. The accuracy of the group response reported by Griffiths and Tenenbaum could be accounted for by supposing that individuals each utilize only two instances. Moreover, the variability of the group data is more consistent with this small-sample hypothesis than with the hypothesis that people utilize veridical or nearly veridical representations of the underlying prior distributions. Our analyses lead to a qualitatively different view of how individuals reason from past experience than the view espoused by Griffiths and Tenenbaum. [source]