IMPROFING QUALITY OF GLUTEN-FREE BREAD FORMULA BY POST-BAKING VACUUM COOLING Anang Lastriyanto*, Sandra Malin Sutan, Bambang Susilo, Afizha Nursabila
Department of Biosystems Engineering - Faculty of Agricultural Technology - Universitas Brawijaya
Jl. Veteran - Malang 65145
*Corresponding author: anangl[at]ub.ac.id
Abstract
Post-Baking cooling is a crucial stage that determines the quality and shelf life of bread, especially gluten-free bread formula. The natural convection cooling method of bread ranges from 120 to 180 minutes, so it requires a relatively larger space and longer contact with air, in addition to the residual water content of the oven has the opportunity to increase water activity or aw. The purpose of this study was to determine the rate of temperature reduction, water content reduction, and texture of gluten-free bread formulas from previous research results. The gluten-free bread made from soy flour and rice flour went through the following stages of production and testing. First, preparing bread dough, mixing, molding, dough conditioning (proofing), and baking based on the research results of Sutrisno et al, 2022. Second, the product of the oven at 160oC where the result of the oven was vacuum cooled using a vacuum cooler designed by the author and natural convection. Thirdly, observing the change in temperature over time, the initial and final moisture content, and the time required to cool with the temperature range between the oven exit temperature to 35oC, thirdly measuring the texture of the bread after cooling. Based on the experimental results, the temperature of the internal part of the bread when it comes out of the oven is 83 + 3oC. The cooling rate required to cool the bread to 350C in vacuum cooling and natural cooling is 0.391oC/second and 0.015oC/second, respectively. The moisture content of the bread from vacuum cooling and natural convection cooling were 35.67 and 41.15% bb respectively or decreased by 13.31%. Meanwhile, the texture of the vacuum-cooled bread decreased by 5.32%. Thus the vacuum cooling process is expected to have future application prospects in bread processing to improve quality and extend shelf life.
