面包面团玻璃化贮存与非玻璃化贮存的品质比较

面包面团分别贮存在家用冰箱(-18℃,非玻璃态贮存)和超低温冰箱(-88℃,玻璃态贮存)中,采用质构仪分析面团在贮存0、7、30、90 d后的面团质构特性,并测定面包比体积。结果表明:(1)非玻璃态贮存面团的黏度、延展性先升高后降低,变化幅度大,而面团弹性、弹性恢复比快速下降;(2)玻璃态贮存面团的黏度、延展性先降低,而后缓慢升高,面团弹性随贮存时间小幅下降、弹性恢复比基本无变化;(3)面包比体积变化情况与面团弹性变化情况相似,说明面团的弹性能较好地反映面包的比体积。玻璃态贮存可以降低重结晶反应速率,减少大冰晶生成,降低面团在贮存过程中的面筋网络破坏;可以降低面团中水分活性,减小水分迁移速率,防止淀粉过度水化。

Comparative analysis on bread dough storage by vitrification and no-vitrification

Bread dough was stored in a domestic refrigerator(-18℃,no-vitrification storage) and ultra-low temperature refrigerator(-88℃,vitrification storage),respectively.The texture of dough was analyzed after 0,7,30,90 days of storage,and the specific volume of bread was also measured.The results were shown as follows:(1) Viscosity and ductility of dough during no-vitrification storage increased at first and then decreased dramatically.Elasticity and elastic recovery ratio of dough during no-vitrification storage decreased fast.(2) Viscosity and ductility of dough during vitrification storage decreased at first and then increased slowly.Elasticity of dough during vitrification storage decreased slightly,while the elastic recovery ratio unchanged during the storage.(3)The changes of bread specific volume were similar to the changes of dough elasticity.So bread specific volume could be better reflected by the elasticity of the dough.Storage by vitrification could reduce the reaction rate of the recrystallization,the large ice crystal formation,and the gluten network damage of dough during storage.Storage by vitrification could also reduce the water activity in the dough and the rate of moisture migration to prevent over-hydration of the starch.