No matter what you do to avoid it, shrinkage is part and parcel of par-baked bread production. Over the years, we have learned to accept a volume reduction of around 15% after the final baking – accompanied by a more compact crumb.
Not even the emulsifier-enzyme systems used to optimise volume in traditional bread production have made a difference. In par-baked recipes, the shrinkage challenge is a really hard nut to crack.
Start with the mix
Our own efforts to find a solution have focused on the whole baking process, starting with mixing. At this stage, the development of the gluten network is fundamental to creating elastic dough with the ability to rise and stay in shape.
Compared to conventional bread-making, par-baked bread dough requires longer initial mixing at slow speed. This ensures maximum water adsorption by the gluten, leaving sufficient free water for the starch to gelatinise during baking and allowing the arabinoxylan fibre to swell. Water bound in the starch is key to optimising bread volume and texture.
More water in the system
We have explored the possibility to reduce shrinkage by employing cellulose gum to keep more water in the system.
With a 0.3% dose of cellulose gum, an additional 3% water must be added to the dough – much more than can be adsorbed by the gluten and starch. This surplus water is then available for absorption by the cellulose gum and arabinoxylan, the strong water-binding property of the cellulose gum limiting water loss when the bread undergoes the final baking.
Unlike other commonly used hydrocolloids, such as guar gum, cellulose gum builds a film around the starch granules, supporting the gluten and starch network after baking. This flexible film further reduces the loss of starch-bound water during the final baking process.
A promising reduction
Our tests with cellulose gum show that shrinkage can be reduced from 15% to less than 10%, a slight further improvement being possible with supplementary enzyme addition. Although still higher than we would like, it’s an undeniable improvement that we will continue to build on. We’ll let you know how we progress.
We used GRINDSTED® Cellulose Gum from the DuPont™ Danisco® portfolio for our trials.