How Much Baking Soda in Water for Pretzels (Soft Recipe)

A full soft pretzel recipe built around the bath: the baking soda to water ratio in cups and grams, how long to dip, and why the alkaline water browns the crust.

Soft pretzels with a baking soda bath need 1/2 cup (about 110 g) soda in 9 cups of water and a 20 to 30 second dip. This 12-pretzel recipe takes about 2 hours and bakes to a dark brown crust with no lye.

A soft pretzel gets its dark brown crust from the bath, not from the oven. Skip the bath and the crust stays pale. Get the bath wrong and you can end up with a metallic aftertaste. This page gives you the ratio in cups and grams, the dip time, and the reason it works.

Why you'll love it

• One bath ratio, written in cups and grams.
• No lye, and an optional baked baking soda bath for a stronger solution.
• A make-ahead route: dip, then refrigerate or freeze.

Prep 30 minutes, rising and resting 80 minutes, bake 15 minutes. About 2 hours in all.

The Food Science / Lab Kitchen Note

Here's why this works. Baking soda is sodium bicarbonate, and a solution of it has a pH of about 8. America's Test Kitchen reports that baking it turns it into sodium carbonate, which has a pH of about 11. Lye (sodium hydroxide) sits at 13 to 14 and is highly corrosive, which is why it calls for goggles and gloves.

The alkaline water coats the surface of each pretzel. An alkaline surface speeds up Maillard browning, the set of reactions that turns the crust dark brown and builds baked flavor. A bath with a higher pH should brown deeper, and the ATK page says exactly that: plain baking soda gives pale, bland pretzels, while the baked soda solution browns deeper with better flavor.

That is also why the baking soda in the bath behaves so differently from the baking soda in Irish soda bread. There it is a leavener that reacts with buttermilk inside the dough. Here it never goes into the dough at all. It only changes the surface.

A little arithmetic of our own shows how different the baths are. The plain bath on this page is about 110 g of soda in about 2,130 g of water, which works out to about 5 percent soda by weight. Sugarologie's baked soda bath is 100 g in 500 g of water, or 20 percent. By our calculation, that is about four times as concentrated, which fits with the fact that baked soda is the stronger alkali.

Plain baking soda, baked baking soda or lye: 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.

The oven times come from two different doughs, so do not swap one into the other's recipe.

Home bakers who try baked baking soda report a darker, better-flavored crust than plain baking soda, but they also say it still does not match a real lye bath. Many bakers pick baking soda or baked baking soda over lye for a plain reason: lye is a single-use, corrosive ingredient that needs gloves and eye protection, and they accept a slightly milder pretzel flavor. This page gives no lye recipe. Treat lye as a professional-style bath and read a source that covers the safety side in full.

Where these numbers come from

The pH figures and the "plain soda is pale" point come from America's Test Kitchen's how-to page on professional-quality soft pretzels at home. That is a practical kitchen page from a test kitchen, not a peer-reviewed study. It does not state a dip time, so we do not borrow one from it.

The dough formula, the weights in grams and the safety steps come from Sugarologie's easy soft pretzels guide, a recipe blog page. Its step 3 says brown sugar while its ingredient list says white sugar, and we followed the list. The plain bath ratio and the 400 F bake come from Peanut Blossom, and the dip time, the egg wash and the make-ahead notes from The Scramble. Both are family food blogs. We found no scientific study on pretzel baths, so none is cited here.

How much baking soda for the bath

The ratio on the card, 1/2 cup in 9 cups of water, is the one Peanut Blossom uses and the most common one we saw. Other sources range from 3 tablespoons in 9 cups to 2/3 cup in 10 cups. By our conversion, that is roughly 40 g to 150 g of soda, using about 224 g per cup as Sugarologie's weights imply. The range is wide, so pick one ratio and stay with it.

Use food-grade, aluminum-free baking soda, and a nonreactive pot. Skip aluminum, which the baked soda guide also warns against.

The sources we read use a boiled bath for the plain version. Peanut Blossom calls its bath a boiled bath, and we found no guidance on simmering versus boiling beyond that. The baked soda bath is the exception: Sugarologie uses it cold.

Dough and shaping notes

Weigh the dough. Twelve pieces of about 75 g each keep the pretzels the same size, and equal pretzels cook in the same time. Roll the ropes to 18 to 24 inches, and know that a shorter rope gives a more bun-like pretzel.

Rest the shaped pretzels uncovered for 20 to 30 minutes. If they feel puffy, refrigerate them for the rest. The dough is meant to be smooth and elastic after kneading, and a quick windowpane check tells you when it is there.

Common mistakes and how to fix them

Leaving the pretzels in the bath too long. Many cooks report that a dip of about 20 to 30 seconds is fine, but a minute or more brings a metallic taste. Set a timer, work one or two pretzels at a time, and drain each one before it goes on the sheet.

Adding the soda to hot water. A Fresh Loaf poster describes the pot boiling over when soda hits hot water. Stir the soda into cold water first, then heat the pot, and use a wide, deep pot so there is room to foam.

Ending up with pale pretzels. Plain baking soda gives paler pretzels than baked soda, per ATK. A weak baked soda solution can also come out pale: one baker reported exactly that when the solution was probably too weak. Measure the soda and the water on the scale if you go the baked route.

Substitutes and swaps

Optional: a baked baking soda bath

This is the no-lye route to a darker crust. It uses Sugarologie's method only. ATK's page gives different times, temperatures and a different bath, so do not mix the two.

Spread about 1 1/2 cups (336 g) of baking soda on a foil-lined sheet pan. Bake it at 300 F (150 C), with the fan off, for 1 hour, then let it cool. The bath is 100 g (about 1/2 cup) of that baked soda in 500 g (about 2 cups) of cold water. Place the pretzels face down for 3 minutes, then bake at 425 F (220 C) for 8 to 12 minutes. Do not carry the 3 minute dip back to the plain bath above, where a minute or more brings the metallic taste.

Coarse salt left on baked soda pretzels for over 24 hours can blister, so salt only the pretzels you will eat the same day.

Nutrition note: calories and sodium per pretzel

Values on the recipe card are estimates calculated from typical USDA FoodData Central figures for all-purpose flour, sugar and salted butter, plus yeast, for one of 12 pretzels. The dough uses unsalted butter, but our sources gave no unsalted values, so we used salted butter's calories and fat as a stand-in and left its sodium out. Table salt is counted at about 4.5 g, our conversion of 3/4 teaspoon.

That comes to about 201 calories and 147 mg of sodium per pretzel. Treat the sodium as a low estimate. The dough accounts for it, but the bath and any coarse salt on top are not counted, and no source we found measures how much sodium a pretzel picks up from the bath. For scale, USDA lists baking soda at 27,360 mg of sodium per 100 g, so by our calculation the 110 g in the pot holds about 30,000 mg in total. We cannot say how much of that stays on the dough.

If you are wondering whether soft pretzels are healthy, this page can give only the numbers above: calories and sodium per pretzel.

Storing, freezing and reheating

Eat the pretzels the day they are made. Peanut Blossom says they will keep in an airtight container for up to 3 days, and that is a blog's guideline, not a food-safety limit. Pretzels with salt that sit longer than a day can blister if you used the baked soda bath.

To make ahead, The Scramble refrigerates the pretzels for up to 24 hours or freezes them for up to 3 months after the bath, unbaked. It bakes them from frozen at 350 F (about 175 C by our conversion) for 20 minutes. To bring leftovers back, warm them in the oven until they are hot through.