Baking Soda Substitute for Pretzels (Baked Soda Bath)

Baked baking soda, washing soda, lye, baking powder and egg wash compared one by one, with the honest food-grade answer and a full soft German pretzel recipe for 8.

Baked baking soda is the swap for pretzels: 1/4 cup (about 56 g) heated in a non-metallic dish at 250 F for 1 hour, then dissolved in 10 cups of boiling water. These 8 soft German pretzels take about 2 hours 30 minutes.

Here's the catch. Baked baking soda starts with baking soda, so it will not help if the box is empty. The other options are narrower than most pages admit, and this guide says plainly where the sources run out. The classic plain bath lives in our pillar guide, how much baking soda in water for pretzels.

What this guide gives you

• Every option compared on sourced data, with "no sourced data" where there is none.
• A no-lye recipe for 8 pretzels, in cups and grams.
• A rinse step, so the crust does not taste bitter.

Prep 30 minutes, rising and resting about 100 minutes, baking 20 minutes. About 2 hours 30 minutes in all, with the soda baked ahead.

The Food Science / Lab Kitchen Note

Here's why this works. Baking soda is sodium bicarbonate. Heat turns it into sodium carbonate (2 NaHCO3 becomes Na2CO3, water and carbon dioxide). America's Test Kitchen, a test-kitchen how-to page and not a study, puts plain baking soda at a pH of about 8 and baked baking soda at about 11. Lye is pH 13 to 14, extremely corrosive, and calls for goggles and gloves.

The usual explanation is that a more alkaline surface speeds up Maillard browning, the set of reactions behind a brown crust. ATK says plain soda leaves pretzels pale and bland, like breadsticks, and describes the baked soda results as a deep-brown crust. Brod and Taylor, a recipe site, calls sodium carbonate by its other name, washing soda. That name is where the trouble starts, and the next section sorts it out.

Some arithmetic of our own on the strengths. German Girl's bath is 1/4 cup (about 56 g) in 10 cups (about 2.37 L) of water, or about 24 g per liter. Brod and Taylor's baked bath is 190 g per liter. By our calculation, that is about eight times as concentrated, and Sugarologie's 100 g in 500 g of water is stronger still. The 56 g is the soda's weight before baking, so the comparison is rough.

What can you use instead of baking soda for pretzels?

Here are the options, one by one, with only what the sources say.

Baked baking soda. The workable route if you have baking soda. Heat turns the bicarbonate into sodium carbonate, and the sources agree that the crust browns deeper than with a plain bath. It does not help if you have no baking soda.

Washing soda. Same chemical name, different product. The Arm and Hammer Super Washing Soda label, as copied on a grocery retailer page, lists sodium carbonate and water and says "Not a food product. Do not consume." That is retailer copy, not the box itself, but it settles the question for a laundry box. FDA regulation 21 CFR 184.1742 lists food-grade sodium carbonate as generally recognized as safe, used with no limit other than good manufacturing practice. We read it on the Cornell LII copy and did not check the current eCFR. We found no verified retailer for a food-grade product.

Food-grade lye. Sodium hydroxide is also listed as generally recognized as safe (21 CFR 184.1763, Cornell LII copy), and that rule gives no bath strength. The CDC NIOSH Pocket Guide lists eye, skin and mucous membrane irritation and burns, and says to prevent skin and eye contact and to irrigate eyes and flush skin right away. We give no lye amount, soak time or concentration, because none is sourced.

Baking powder. We found no source that uses it in a bath. It is a dough leavener, not a bath ingredient. For leavener swaps in dough, see baking soda replacement.

Egg wash only. One blog, Just Plain Cooking, photographed four versions. With egg wash but no bath, the pretzels were not much better than twisted bread and still did not really look like soft pretzels. With both a bath and egg wash they were rich and chewy. That is a single anecdote, not a controlled comparison.

Pretzels without baking soda

Without baking soda the choices are the ones above: food-grade sodium carbonate or lye, or an egg wash that gives a poor result. If it is the oven you are changing, see our air fryer soft pretzels.

Three baths side by side: a data comparison

This table lines up what the sources say. It is a comparison of published data, not a record of batches we baked. Where no source gave a number, the cell says so.

Baked soda numbers do not agree

The sources contradict each other on how to bake the soda and how strong to make the bath. We show the conflict instead of averaging it.

The recipe below uses German Girl's numbers only. Do not carry the 3 minute dip or the 300 F bake into it.

Where these numbers come from

The pH figures and the bake-at-250-F method come from America's Test Kitchen's how-to on professional-quality soft pretzels, a test-kitchen how-to page, not a study. The recipe card follows German Girl in America, a recipe blog, which warns that the sodium carbonate is toxic if eaten. The rinse and the 190 g per liter bath come from Brod and Taylor, a recipe site. Sugarologie is another recipe blog and the source of the 300 F method and the salt blister warning.

The rest is a mix of personal accounts and rules. A columnist at the Arkansas Democrat-Gazette wrote in 2020 that her first baked-soda batch, boiled without a rinse, was inedible, bitter and soapy. That is one person's account, not a trial. Many cooks report that the baked or washing soda dip needs a plain water rinse, and two recipe sites say the solution tastes bitter. The safety lines come from the label copy on a grocery retailer page, the FDA rules on sodium carbonate and sodium hydroxide as read on the Cornell LII site, and the CDC NIOSH Pocket Guide. We found no scientific study on pretzel baths, so none is cited.

Tips for your kitchen

Check the label. If it says "Not a food product," it is not for the pretzels, whatever the chemical name.

Use a non-metallic dish to bake the soda and a non-aluminum pot for the bath. Label the jar of leftover baked soda, keep it airtight, and keep it away from children and pets. Sugarologie says it keeps about one month.

Rinse, then salt. Coarse salt left on baked-soda pretzels for more than 24 hours can blister, so salt only what you will eat the same day.

Common mistakes and how to fix them

Skipping the rinse. Many cooks report bitter, soapy pretzels without it. Rinse each pretzel briefly in cool plain water before it goes on the sheet.

Mixing numbers from different sources. A 3 minute dip suits Sugarologie's strong cold bath and would be a very different thing in German Girl's boiling one. Pick one source and keep all its numbers together.

Treating the laundry box as the ingredient. A matching chemical name does not make it food. Buy baking soda to bake, or a product sold as food-grade.

Substitutes and swaps

Nutrition note

The card values are estimates we calculated from typical USDA FoodData Central figures for bread flour, brown sugar, dried yeast and table salt, for one of 8 pretzels. That comes to about 198 calories and 583 mg of sodium. Most of the sodium comes from the 2 teaspoons of salt in the dough. The bath, which is baked soda in water, and any coarse salt on top are not counted, and no source we found says how much sodium the pretzel picks up from the bath. So treat 583 mg as a low estimate.

Storing, freezing and reheating

German Girl in America says the pretzels are at their best the day they are made. To keep them longer, freeze them airtight for up to 2 months and reheat at 350 F (about 175 C by our conversion) for 3 to 4 minutes.

Leftover baked soda goes in a labeled, airtight jar away from children and pets. Sugarologie says about one month. The baked soda for this recipe can be made 1 to 2 days ahead.