Par-Baking Sourdough

I am often asked how to scale up production for large events while still having all of the loaves freshly baked. Even with a bread oven, there are many times when it would be helpful to boost your standard production numbers. In this post, I will review a method that we have used successfully.

A Look At Par-Baking

At our bakery, we began testing a process for par-baking at the request of a wholesale customer. They delivered bread to their customers on Tuesdays, and many of them wanted bread that would still be fresh for the weekend. The process we tested included partially baking sourdough, cooling it, wrapping it, and freezing it. The frozen loaves could then be delivered with instructions for the final bake at home. This way, the customer could have a fresh loaf whenever they wanted, and enjoy the smell of freshly baked bread in their kitchen!

Our initial concern was whether the quality of our bread would suffer. We extensively tested the process, from baking and storing to defrosting and final bake. We then performed blind taste tests at the bakery to see if there was any notable difference. After being entirely satisfied that we could not tell which was par-baked and which was not, we did further testing with customers who also could discern no difference in quality.

With our testing going so well, we started offering the option to retail customers, allowing them to take a loaf or two for later and finish it in their home oven whenever they like. This also helped us manage production demands for busy weekends, knowing that we had plenty of par-baked loaves on hand.

Par-Baking Method

The concept is pretty simple–we bake the bread as normal, but entirely under steam injection, so the Maillard reaction and caramelization don’t have a chance to fully color the crust. Once the oven spring is complete and the core temperature of the bread reaches at least 180°F (82°C), we pull the loaves and allow them to fully cool on racks before wrapping them in cling film and freezing. We freeze them all in a single layer to prevent them from collapsing, then once frozen, stack them to conserve space.

The precise time and temperature for the initial bake will vary depending on the oven, but a range of 450°F - 500°F with full steam for 20-25 minutes is a good place to start. Use a temperature probe to make sure you reach the target core temperature, and that the loaves have sufficient structure so they don’t collapse.

To finish the loaves, simply defrost them at ambient temperature in the cling film, then bake at 450°F until the crust is colored to your liking. The bread is fully cooked, but a range of 10-20 minutes at this temperature should crisp them up nicely. You can also fit far more loaves in the oven this way, since there is no worry about them spreading and baking into each other.

Provided you have adequate freezer space, this is a great way for budding cottage bakers to be able to produce additional bread to meet market demand. And once you have your process fully dialed in, you’ll be able to easily reproduce your results.

Other Par-Baking Benefits

Not only does this method produce high-quality bread, but it also comes with a few more potential benefits. Many studies show that freezing increases the amount of resistant starches, through a process called retrogradation during cooling. These resistant starches help lower the glycemic index even further, and they have prebiotic and other nutritional benefits. Finally, you can also achieve a crisper overall crust in the final loaf, due to the added surface area of the loaf that occurs during the retrogradation process!