2009-02-16

Baking powder

Update 2009-03-01: I found a LOT more reference materials, and it's just much cleaner to integrate them into the original post than to write them out as addenda.

In my previous post I had a brief discussion about homemade baking powder. I think, though, that it will be useful to devote a separate post to baking powder in general and expand on the topic a bit.

CONTENTS

BAKING POWDER AND LEAVENING

Baking powder belongs to a class of ingredients known as leaveners, the purpose of which is to produce adequate gas pockets (bubbles, if you will) so that the dough or batter will rise and lighten the texture of baked goods. Further, baking powder and baking soda are known as chemical leaveners, which release gas through a reaction between alkaline and acidic ingredients. Other leaveners used in home baking include yeast, which acts biologically, and egg whites, which leaven mechanically by the air pockets formed from whisking. Once in the oven, steam also contributes to the leavening of baked goods.

Baking powder is made by combining baking soda with one or more dried acids. Baking soda, which is also known as either bicarbonate of soda or sodium bicarbonate (formula NaHCO3), is an alkaline (or base) material and will release carbon dioxide gas (CO2) when dissolved with the help of an acid, so it is used in recipes that contain ingredients such as buttermilk, natural cocoa powder, or fruit juices. When we combine baking soda with dried acid(s), we create a complete leavening system that is then activated (i.e., gives off gas) by introducing moisture into the mix.

Note, however, that baking soda will release carbon dioxide not only as it dissolves with acid, it will also break down and release gas at temperatures above 120 °C (250 °F) without any acids involved1. In other words, carbon dioxide is not produced from a combination of acid and baking soda, but is released as baking soda itself breaks down. Baking soda is the carbon dioxide source2, and the acid-soda reaction is really more accurately described as acid-activated decomposition of baking soda. The generalized equation for the breakdown of baking soda with acid (denoted here as H+) is:

NaHCO3 + H+ → Na+ + CO2 + H2O
The thermal decomposition of baking soda is:
2 NaHCO3 + heat → Na2CO3 + CO2 + H2O3

SHELF LIFE

Since moisture is what triggers baking powder into action, it must be kept dry during storage. To prolong shelf life, a starch (such as cornstarch) is added to commercially-made baking powder to absorb moisture and prevent its alkaline and acidic components from reacting with each other prematurely. This moisture-absorbing capacity isn't infinite, of course, so manufacturers will indicate an expiration date on the product's package. To be on the safe side, you should throw out any baking powder that has expired. Oh, foods made with out-of-date baking powder aren't harmful per se, but the shame from turning your cakes and breads into bricks might just kill you (or at least make you wish you were dead).

If, on the other hand, you like to live on the edge or just can't find the expiration date, you can test baking powder's effectiveness by dropping a small amount of it into just-boiled water: if it foams vigorously, then the powder is still good; if it sinks to the bottom, then the powder has passed its prime.

video
Testing baking powder (verdict: still good)

How much baking powder and water should you use for this test? Considering the large discrepancies in published guidelines—for example, Cook's Illustrated4 recommends using 1/2 tsp powder in 1 cup water, while Fine Cooking recommends 1 tsp powder in 1/3 cup water—I think it's safe to conclude that exact quantities are not crucial.

SINGLE-ACTING VS. DOUBLE-ACTING

Baking powder is typically divided into two categories: single-acting and double-acting. Single-acting baking powder, however, can be either fast-acting or slow-acting5. As the name implies, single-acting powders undergo one chemical reaction: the acid in a fast-acting powder dissolves relatively quickly so that the gas-producing reaction takes place upon mixing with liquid; on the other hand, the acid in a slow-acting powder requires either prolonged time exposure or temperatures above 120 °F6 in the batter to dissolve. Double-acting baking powders contain both fast- and slow-acting acids so that gas pockets can be formed in the dough or batter both as it is mixed and after it is in the oven; allowing two reactions to take place increases baking powder's reliability as it makes the length of time between mixing and baking less critical.

Some of the commonly-used acids in baking powder and their reaction times are listed below7:

Leavening acid Abbrev. Formula Reaction time
Cream of tartar KC4H5O6 Immediate
Glucono delta lactone (also called δ-gluconolactone or D-glucono-1,5-lactone) GDL C6H10O6 Slow at room temperature
Monocalcium phosphate (also called calcium acid phosphate) MCP Ca(H2PO4)2
[or · H2O]
Immediate (but see Rumford discussion below)
Sodium aluminum pyrophosphate NaAlP2O78 Slow at room temperature
Sodium aluminum sulfate SAS NaAl(SO4)2 Slow and heat-activated
Sodium aluminum phosphate SALP 1-3-8 NaAl3H14(PO4)8

· 4 H2O
Heat-activated
Sodium aluminum phosphate SALP 3-2-8 Na3Al2H15(PO4)8 [anhydrous] Heat-activated
Sodium acid pyrophosphate SAPP9 Na2H2P2O7 Variable

Variable reaction time? How can that be?

Well, it turns out that a leavening acid's molecular formula isn't the only determinant in its reaction speed. Manufacturing-related parameters such as heat treatment, particle size, or coating materials can all be manipulated to affect the specific acid's behavior without altering the chemical make-up of its main constituent. Specifically, SAPP is manufactured in multiple grades, each with a different reaction rate10, 11.

ALUMINUM-FREE BAKING POWDERS

Most of the baking powders sold to US consumers today are labeled as double-acting, and market leaders Calumet and Clabber Girl both use SAS as the slow-acting acid. I'm not a medical scientist so I can't tell you whether the health concerns over aluminum are valid or not, but I do know that its metallic flavor is unpleasant to some, so it's worth your time to seek out aluminum-free baking powders. These are the products I'm aware of, in alphabetical order (comments are "to the best of my knowledge"):

CaCO3 = calcium carbonate. MgCO3 = magnesium carbonate. KHCO3 = potassium bicarbonate.
Brand Ingredients Sodium Free? Comments
Argo Acid 1: MCP
Acid 2: SAPP
Base: baking soda
Starch: cornstarch
No Smallest container is 12 oz.
Bakewell Cream Acid 1: SAPP
Acid 2:
Base: baking soda
Starch: redried starch12
No Mainly sold in New England. Packaging does not look airtight.
Bob's Red Mill Acid 1: MCP
Acid 2: SAPP
Base: baking soda
Starch: cornstarch
No Mainly found in specialty-foods stores. Packaging does not look airtight. Smallest container is 16 oz.
Ener-G Acid 1: citric acid
Acid 2: GDL
Base: CaCO3 and MgCO3
Starch:
Yes Mainly found in specialty-foods stores. Kosher for Passover. Smallest container is 7.05 oz (200 g).
Hain Acid 1: MCP
Acid 2:
Base: KHCO3
Starch: potato starch
Yes Mainly found in specialty-foods stores. Kosher for Passover. Not labeled as double-acting.
Rumford Acid 1: MCP
Acid 2:
Base: baking soda
Starch: cornstarch
No Best availability nationwide. Made by Clabber Girl. Smallest container is 4 oz.

As mentioned above, baking powder has a limited shelf life, so I would recommend getting the smallest and best-sealed package available.

Ener-G's formulation is unusual for consumer-oriented baking powders, using citric acid and GDL, two bases, and no starch. Glucono delta lactone is derived from glucose and is, in spite of the impression its name may give, dairy free. The calcium and magnesium carbonates provide alkalinity (calcium carbonate is the active ingredient in many antacid tablets), and magnesium carbonate further functions as a drying agent so that no starch is needed in this baking powder. The company recommends using twice as much of its baking powder as regular double-acting powder to achieve the same leavening effect.

Of the single-acid powders, only Hain does not label its product double-acting. Since the reaction rate of SAPP can be made to vary, it's possible that Bakewell Cream contains a mixture of multiple SAPP grades so that the powder can provide leavening action at different temperatures. But what about Rumford? Isn't MCP only a fast-reacting acid? Well...

RUMFORD BAKING POWDER

Yeah, I know, giving this brand its own heading seems like so much product placement, but among the lay food-science types, there is some confusion over how this baking powder really works, so I think we need to talk about it.

Rumford lists only three ingredients for its baking powder: calcium acid phosphate, bicarbonate of soda, and cornstarch. Notice from the top table that calcium acid phosphate is just another name for MCP, which is classified as a quick-acting acid. However, the product canister is also marked "double acting." How can that be possible when there is only one leavening acid present?

Well, not all MCPs are created equal. For starters, it's available in two forms: with a water molecule attached to it (monocalcium phosphate monohydrate, Ca(H2PO4)2 · H2O), or without water (anhydrous monocalcium phosphate, Ca(H2PO4)2). It may be counterintuitive, but MCP monohydrate is a granular powder13 even with the water hanging around—that makes as much sense, though, as baking powder releasing a gas upon decomposing while it normally exists as a powder. MCP monohydrate is indeed a quick-reacting acid; on the other hand, anhydrous MCP is typically manufactured with a coating to protect the acid from exposure to liquids and thus delay its reaction. The following graph shows the slower room-temperature gas-release rate that results from dissolving baking powder with coated anhydrous MCP as compared to MCP monohydrate14:

Room-temperature carbon dioxide relase of baking soda and leavening acids

In the general case, baking soda reactions with coated anhydrous MCP will release 15% of the available CO2 during the first 2 minutes, 35% during the next 10–15 minutes, and the final 50% during baking15. Specifically, we can compare the gas-release rates of several different baking powders made by Clabber Girl:

Product (PDF datasheets)16 Leavening acids Approx. CO2 release (mix/bake)
Rumford MCP 60%/40%
Clabber Girl SAS MCP, SAS 30%/70%
Clabber Girl SALP MCP, SALP 3-2-8 30%/70%
Fleischmann's MCP, SAPP 10%/90%

I believe the SALP and SAPP formulations are available only to commercial bakers, which is why Fleischmann's is not listed in the aluminum-free baking powder table above.

At any rate, based on this knowledge I think we can make the following conjectures on how Rumford can label itself as "double acting":

  • Even though coated anhydrous MCP has a faster room-temperature reaction rate than aluminum-containing leavening acids (compare against SALP in the graph above), it may be delayed enough so that baking powders containing only coated anhydrous MCP can approximate the performance of double-acting powders without actually having a two-stage gas-release characteristic. Since the coating material is likely to show up under analysis only as trace elements, Rumford may not be required to specify this material on the ingredients list.
  • It's also possible that Rumford contains both uncoated and coated MCP so that there does exist two spikes of gas production. However, as the main constituents of both MCP types are identical, they may then be shown in the ingredients list only once.
  • Further, in Bakery Technology and Engineering, the author states that "[d]ouble-acting baking powders are really a version of the slow-acting type which exhibit somewhat more gas production potential during mixing and on the bench."17 Based on this, we should be able to apply the same description in reverse to MCP-only baking powders such as Rumford, as it uses a fast-acting acid that exhibits delayed gas production behavior.
  • Finally, "double acting" may be a phrase with no regulatory definition, at least in the US. If this is the casee, then Rumford may well declare, on its own, that its baking powder is "close enough" to the two-acid powders in behavior for the "double acting" label to be suitable. In other words, they did it because they felt like it and could get away with it. I am, however, not skilled enough at searching through US food regulations to confirm or deny this conjecture (I've tried, really).

DO BRANDS MATTER?

The conclusion from Cook's Illustrated's March 2003 baking powder test was that all the powders in the review showed similar performance. This may be a result of the US FDA regulations that require all baking powders to release at least 12% CO218 coupled with the constraints imposed by the acid-base chemistry itself, leading to only small differences in the amount of gas released from each brand. In other words, aside from the concerns over aluminum, we should reasonably expect double-acting baking powders from the leading brands to be interchangeable with each other in recipes.

Update 2009-08-19: Baker Debra Wink at the excellent bread-making resource The Fresh Loaf disagrees, and has empirical evidence that different brands exhibit different behaviors.

HOMEMADE BAKING POWDER

Sift or mix the following ingredients thoroughly:
2 partsCream of tartar
1 partBaking soda
1 partCornstarch (optional)
Each "part" is measured by volume (e.g., teaspoons, tablespoons, cups—just keep them all the same). A 2:1 ratio between cream of tartar and baking soda is the classic formula, although to be exact, the ratio should be 5:219. As mentioned above, the cornstarch is for moisture absorption and is only necessary if you're going make a large batch of baking powder and store it for a while; otherwise just make the quantity needed for each recipe, skip the cornstarch, and use it right away (keep in mind that if you've skipped on the cornstarch, then you should use less of the resulting powder than the quantity specified in the recipe—see the Substitutions section below for details). If my understanding is correct, excluding cornstarch also makes this baking powder kosher for Passover.

Since cream of tartar is a quick-reacting acid, homemade baking powder is single-acting. To make sure the leavening action from this baking powder doesn't fizzle out prematurely, place the batter into the oven as soon as possible after it is mixed. For extra insurance against early fizzling, it's also been suggested that you should add the baking soda and cream of tartar into your baking mixture separately, which seems like a good idea.

SUBSTITUTIONS

To substitute for 1 tsp double-acting baking powder, follow one of the options below (based mainly on David Joachim's The Food Substitutions Bible20):
  • For homemade baking powder without cornstarch, either use ¾ tsp (i.e., ½ tsp cream of tartar + ¼ tsp baking soda) based on the classic formula, or 7/8 tsp (5/8 tsp cream of tartar + ¼ tsp baking soda) if your measuring tools are accurate enough. Place batter in oven as soon as possible.
  • 1¼ tsp single-acting baking powder. Place batter in oven as soon as possible.
  • ¼ tsp baking soda + ½ cup buttermilk. You will then need to reduce the other liquids in the recipe by ½ cup. This will alter the flavor of the recipe.
  • ¼ tsp baking soda + ¼ cup molasses. You will then need to reduce the other liquids in the recipe by 3 tbsp and adjust the sweetener. This will alter the flavor of the recipe.
It seems a bit confusing that ¾ tsp of homemade baking powder and 1¼ tsp of of single-acting baking powder are both listed as appropriate substitutes for 1 tsp double-acting powder. I'm guessing that the 1¼ tsp quantity refers to commercially-made single-acting baking powder, which may have less leavening power or have been bulked up with non-reacting ingredients, but not having the author's resources, I really can't tell. Based on the suggestions for homemade powder without cornstarch, though, you should be able to use the same amount of homemade pre-mixed (that is, containing cornstarch) baking powder to substitute for commercial double-acting powder.

HOW MUCH SHOULD YOU USE?

You mean, other than following the recipe? Okay, I won't be so flip about it. As I'm sure you can figure, too little baking powder will mean too little rise and a dense result in your baked goods, which is undesirable. But does this mean more is better? Well, only to a degree. Too much baking powder creates supersized bubbles that burst and deflate—imagine blowing up bubblegum so much that it pops and gets all over your face—which, again, leads to dense baked goods with an added helping of nasty taste from the extra powder. So, then, what is the magic amount?

It's actually a little complicated. Shirley Corriher explains21:

The general rule is 1 to 1¼ teaspoons of baking powder per cup of flour in a recipe....[However,] many variables determine the proper amount of baking powder to be used, and you need to adjust the general rules for your own cooking conditions. More leavening can be used if the recipe calls for a lot of heavy ingredients like chopped fruits. When you change pan size, the amount of baking powder should be altered.
Corriher further notes that for the same amount of batter, the shallower it is in the pan (that is, with wider pans), the less powder you need. She also references Rose Levy Beranbaum's The Cake Bible for the exact amount of leavener to use relative to different pan sizes and batter quantities, but I don't have that book so I can't tell you more about it.

HIGH ALTITUDE BAKING

The rule of thumb is that general-purpose recipes should work well from sea level up to about 3,000 feet (910 m). Above that, the amount of baking powder as well as baking soda should be reduced. I have no first-hand experience with this, but the literature suggests that determining exact reductions is a somewhat complex issue. King Arthur Flour has some general guidelines, and the Colorado State University Extension makes slightly different recommendations specific to cakes while noting "[o]nly repeated experiments with each recipe can give the most successful proportions to use." In BakeWise, Shirley Corriher mentions that cookbook author Susan Purdy has done just that, making "all kinds of baked goods at sea level, 3,000, 5,000, 7,000, and 10,000 feet"22 (910 m, 1,520 m, 2,130 m, and 3,050 m), and published her results in Pie in the Sky. I have not seen this book myself, however.

SODIUM-FREE BAKING POWDERS

As noted in above (under aluminum-free baking powders), Ener-G and Hain are the two brands of sodium-free baking powder that I know of. Ener-G recommends using twice as much of its powder as regular baking powder to achieve the same leavening effect. Hain provide no such guidance, although some have tested it and found that it is one-for-one compatible—that is, use the same quantity—as regular powder. Other than these two specific instances, however, general guidelines vary (or are unreliable?). Most sources on the Internet recommend using 1.5 times as much sodium-free powder as standard baking powder. This advice, however, does not take into account the specific formulations of the different sodium-free powders. Although the greater atomic mass of potassium over sodium means that 19% more potassium bicarbonate (by weight) is needed to neutralize a given amount of acid as compared to baking soda23, the ingredients listing doesn't tell us how much potassium bicarbonate is actually contained in the product that we buy. The Williams-Sonoma Kitchen Companion recommends doubling the quantity24 but does not indicate the specific ingredients involved.

REFERENCES AND NOTES

  1. W.P. Edwards, The Science of Bakery Products, Royal Society of Chemistry, 2007, p. 70
  2. Lallemand Inc., Lallemand Baking Update (PDF), Vol. 1 No. 12, 1996
  3. W.P. Edwards, The Science of Bakery Products, p. 71
  4. "Baking Powder Expiry," Cook's Illustrated, 11/2002
  5. Shirley O. Corriher, CookWise, William Morrow-Harper Collins, 1997, p. 73
  6. Christopher Kimball, The Cook's Bible, Little, Brown, 1996, p. 348
  7. Based on Harold McGee, On Food and Cooking (revised ed.), Scribner-Simon & Schuster, 2004, p. 533, with additions and changes from other sources.
  8. I was unable to find a formula for sodium aluminum pyrophosphate—or, in fact, any mention of it in food industry literature of its use as a baking powder ingredient. Anyhow, given the charges of sodium (Na1+), aluminum (Al3+), and the pyrophosphate compound (P2O74-), this formulation seems reasonable.
  9. This item is not listed in McGee's table, and he uses SAPP as an abbreviation for sodium aluminum pyrophosphate. However, all the food industry references I've come across use SAPP as the shorthand for sodium acid pyrophosphate, so that's the convention I'm following here.
  10. Samuel A. Matz, Bakery Technology and Engineering (3rd ed.), Springer, 1992, pp. 67, 69
  11. Clyde E. Stauffer, Functional Additives for Bakery Foods, Springer, 1990, p.196



  12. Based on the description of another product, I assume that "redried starch" is cornstarch.
  13. George A. Burdock, Encyclopedia of Food and Color Additives, CRC Press, 1996, p. 409
  14. Graph based on Robert C. Lindsay, Food Chemistry (3rd ed.), CRC Press, 1996, Owen R. Fennema, Ed., p. 772.
  15. Shirley O. Corriher, BakeWise, Scribner-Simon & Schuster, 2008, p. 47
  16. These datasheets are stored under two different sections of Clabber Girl's website (Foodservice and Ingredients), and it's a bit confusing because there are multiple datasheets, with different gas-release rates specified, for each product. I don't know why this is, but I've selected the most rounded-off figures for my table.
  17. Samuel A. Matz, Bakery Technology and Engineering (3rd ed.), Springer, 1992, p. 71
  18. Ibid.
  19. Harold McGee, On Food and Cooking, p. 534
  20. David Joachim, The Food Substitutions Bible, Robert Rose, 2005, p. 38
  21. Shirley O. Corriher, CookWise, p. 138
  22. Shirley O. Corriher, BakeWise, p. 50
  23. W.P. Edwards, The Science of Bakery Products, p. 71
  24. Mary Goodbody, Carolyn Miller, and Thy Tran, Williams-Sonoma Kitchen Companion, Oxmoor House, 2000, p. 23.

32 comments:

  1. this post is very interesting! thank you!

    ReplyDelete
  2. I was joking in my post about tofu. I happen to like it plain as well.

    ReplyDelete
  3. I googled "baking soda in cupcakes" and your posting on baking powder appeared. Thanks for what seems to be extremely well researched information with fantastic moments of sarcasm. Actually made learning about baking powder memorable! Now back to baking (with less baking soda that is aluminum free)...

    ReplyDelete
  4. How long does Baking Soda(boiled in water to dissove it) last??? Can I make gallon of it & use for a year with full effect? Thanks, Frank Homsher,
    email: homsher.frank@gmail.com

    ReplyDelete
  5. Frank, I don't know what your intended use is for the dissolved baking soda, so I can't answer whether it'll be good "for a year with full effect" or not. I will say that since baking soda is soluble in water (that is, breaks down, beginning with the sodium and carbonate ions), what you end up with won't be "baking soda in water" but "ions in water." Some carbon dioxide will also escape, especially with boiling. In brief, this is what happens:

    1. NaHCO3 + H2O = Na + HCO3 + H2O
    2. HCO3 + H2O = H2CO3 + OH
    3. H2CO3 = H2O + CO2
    4. CO2 escapes

    Provided that you use less than 1 part baking soda per 10 parts water (by weight), this solution will remain stable. So if the ionic solution is what you want, then I don't see any reason why it wouldn't keep for at least a year. Please keep in mind that I have no direct experience with long-term storage of dissolved baking soda, so this is all just hypothesizing based on my knowledge of chemistry.

    Incidentally, sodium bicarbonate injection solution is used medically, so you may be able to find out its expiration period by visiting your local pharmacist.

    ReplyDelete
  6. Thanks so much for your information. I am researching why a cake I have made many times had a problem recently. I think I may now know why. Thanks again! Mary

    ReplyDelete
  7. Oh very fascinating, I thank you for your time in presenting this wonderful info about baking powders on the Bowl of Plenty. If the manufacturing facilities took this info to the market, all the data you collected may become out-dated and altered under the heading of new and improved. Are all the SAPP and the sub class 'food grade coming out of china?
    I have found my body has become intolerant of corn in any form therefore; cornstarch must be removed from my diet. I love to cook and bake with sourdough breads being my most satisfying success. My last culture was three years young when I used it last.

    I am writing in the hopes that you might know a product developer. I am in need of SAPP Food Grade for my uses without the cornstarch. I know clumping is inevitable but I do not want a 55-gallon drum of the stuff hanging around. Are there any brands that do not contain citric acid and/ or cornstarch? I would love to get back into the kitchen without intolerance issues in the forefront of my creations.

    Just last month I came down with a fever of 102 degrees Fahrenheit from collective used of citric acid.So through sessions of shock I know what to avoid. Pain is such a reliable teacher!

    Thank you for any efforts you send my way.
    Margie
    Herbal100@peoplepc.com
    4-15-10

    ReplyDelete
  8. Margie, I don't work in the food industry, so I don't know any product developers.

    For a listing of SAPP suppliers, you can search on its CAS number (7758-16-9). I found some — for example, here and here — that are based in the US, although it isn't specified if their products are food-grade or not. As you can imagine, these suppliers are likely to package their products in sizes suitable for industrial customers and not for home use. For smaller quantities, you'll need to buy from laboratory-supplies companies (search for either "laboratory equipment" or "laboratory chemicals"). It is unlikely that these companies will publish the origin of their materials or if it is food-grade, but you may still be able to find out just by asking.

    I'm not sure if it's a good idea to make your own baking powder at home with SAPP, though. As I mentioned in the post, SAPP is made in several grades, so you'll need to make sure that what you've ordered really has the properties you desire. You'll also need to know the neutralizing value of SAPP in order to mix in the correct ratios of SAPP and baking soda.

    So, before you turn your kitchen into a lab, I'd explore other options. As I mentioned in the post, you can make homemade baking powder by combining only cream of tartar and baking soda. If you need to store the mixture for later use, then you can add potato starch to it instead of cornstarch. Speaking of which, Hain's baking powder contains neither cornstarch nor citric acid, so you can try to find it at a natural-foods store (e.g., Whole Foods).

    ReplyDelete
  9. Margie, I just had another thought. Look for baking powder that's kosher for Passover. These are made without cornstarch, and are unlikely to contain citric acid (as it is an unusual ingredient for baking powders). One brand I'm aware of is Gefen. As none of the places selling it online list its ingredients, you should still ask and make sure first, but it's another potential option.

    ReplyDelete
  10. Hi There,

    No one seems to be making a distinction between baking SODA (which I use in my laundry and for brushing my teeth and is much grainier/coarser in consistency) and baking POWDER (which I use in baking and is a fine powder). My grandfather always used baking soda for brushing his teeth, which turns out to be smart because it creates an alkaline environment in the mouth (which discourages the formation of cavities) and is mildly abrasive). The soda also makes an excellent antacid. However, I would very much appreciate confirmation that there is no aluminum in baking SODA (I buy Arm & Hammer in the large orange-yellow box). If no one here knows for sure, I might email A & H to see if they can tell me, though my confidence in corporations is not all that high. Thank you! :) Val

    ReplyDelete
  11. Hi Val, the chemical name for baking soda is sodium bicarbonate, and its formula contains sodium, hydrogen, carbon, and oxygen. That's it. No more. There is no aluminum in baking soda.

    ReplyDelete
  12. Hi!thanks so much for the info about Baking Powder and Baking Soda. I'm not a graduate of any culinary and baking courses but it came that I discovered - I have a gift in baking! I've always wondered why I always get rough texture and it doesn't rise as expected. But because of your helpful info now somehow I'm getting better results. I understand that every baker have their own secrets and that it's their discretion whether or not to share the full process or technique. Nonetheless,thanks for the advise. Keep it up!God bless!

    ReplyDelete
  13. I would like to make my own baking powder in small batches (250grams), however as I live in Europe we mostly use measurements by mass instead of volume which is chemical more accurate.

    What is the correct ratio by mass between cream of tartar, baking soda and cornstarch considering the more accurate 5:2 ratio?

    Many thanks, Edwin

    ReplyDelete
  14. Hello Edwin. By weight, you should use 45 g of baking soda per 100 g of cream of tartar. Since the cornstarch is just a filler, it isn't necessary to measure its quantity exactly. If you want, you can use 55 g of cornstarch to make up 200 g of baking powder. Scaled up to 250 g, the quantities would be:

    * 56 g baking soda
    * 125 g cream of tartar
    * 69 g cornstarch.

    For more background information, you can read this PDF under the "Neutralizing Values" column.

    ReplyDelete
  15. Many thanks for the calculations and the link to this great PDF with the complete chemical reaction ratios. I found the whole teaspoon measurement business not chemical accurate enough for my liking and your information solves my 'problem' completely!

    ReplyDelete
  16. I didn't see any information about how much baking soda per cup of flour. Did I miss it? Thank you.

    ReplyDelete
  17. Well, this post is about baking powder, not baking soda. Anyway, Shirley Corriher says on p. 59 of Bakewise to use 1/4 tsp baking soda per cup of flour.

    ReplyDelete
  18. Much about baking(bread,cookies etc.)is discussed when I did some searching on leavenng agents. How about shedding some lights on proper composition of the base(bicarbonate of soda) and its acids(MCP,SALP, SAPP and the likes)for (dry)padding or batters for fried chicken?

    ReplyDelete
  19. The general rule is to use 1 teaspoon of baking powder for each cup of flour, and this works whether you're baking or frying. I don't think the exact composition of what goes into the baking powder matters much for frying chicken, and there's really no point to exploring the details here since these materials are generally not available to home cooks (unless you're willing to order industrial quantities of them, that is).

    ReplyDelete
  20. Is there any aluminum-free baking powder (or aluminum-free rising agent) that releases CO2 only by heat? Many thanks.

    ReplyDelete
  21. Based on the leavening acid table above, it appears that the Ener-G powder (which uses GDL as its acid) would work by releasing CO2 at high temperatures. I have not used this product myself, however.

    ReplyDelete
  22. please help me with the formulation of baking powder using SAPP , corn starch & bicarbonate of soda .

    the shop I buy from in place of cream of tartar they got SAPP food grade & no formulation , just a rough sketch . please help

    ReplyDelete
    Replies
    1. Samuel Matz gives a formula of 40.38% SAPP, 30.59% bicarbonate of soda, and 29.03% starch for slow-acting baking powder, and Clyde Stauffer gives a formula of 44% SAPP, 30% bicarbonate, and 26% starch for double-acting baking powder.

      Delete
  23. Hello. Thank you for your well-written post about baking powder. It was nice of you to take the time to research information about the chemical processes involved and the differences in the ingredients used in various brands of baking powder. I am not a professional baker or scientist, but I did learn a lot from reading this article. Personally, I have used Clabber Girl for years. Recently, and with all of the conflicting health reports about ingesting aluminum, I decided to switch to Argo baking powder. In most of my trusted old cake recipes, I noticed that after the switch to Argo baking powder, the cakes rise rather quickly in the oven and, regarding cupcakes, they overflow the liners in the pan and stretch across the rim. Is this the result of the "variable" reaction time that you noted was characteristic of the SAPP, or have I just lost my baking skills over the years? Other than using the Argo baking powder, I am not sure what I am doing wrong (and I do not think that my oven temperature is off, either.) Though not a scientific test, I dissolved 1/4 t. of Clabber Girl baking powder in 1/4 cup of hot water and did the same with the Argo baking powder. I noticed that the Clabber Girl released bubbles that generally stayed in the corner of the bowl, but the water did bubble steadily and continuously for a few minutes (I could hear the bubbling.). The Argo baking powder, when dissolved in a separate bowl of hot water, bubbled slightly more strongly, and the bubbles spread across the bowl. However, the bubbling was less steady and did not seem to last as long as the bubbling of the water with the Clabber Girl dissolved in it. If they are both double-acting, do you have any idea why they seem to react differently when dissolved in hot water or why they seem to perform differently in the same cake recipe? Thanks in advance for any suggestions or help. --K.D.

    ReplyDelete
    Replies
    1. I think the strength and longevity of the bubbles is due to the powders' different formulations, but the location is probably caused by microscopic differences in the cups (in other words, try again and you'll probably see a different pattern). I haven't compared cakes, but I've noticed that quick breads baked with Argo rise better than they do with Rumford. Is "better" too much in your case? Perhaps. Over at The Fresh Loaf, Debra Wink compared several baking powders on biscuits and found that Argo's rise was similar to that of Clabber Girl. Now, biscuits aren't cakes, of course, but she does mention that Rumford is her favorite powder for cakes, so perhaps you can give that a try.

      Delete
  24. Thanks so much for your information.
    I would like to make my own single acting baking powder, which will start reaction only when it heated to a certain temperature and will release most of the available CO2 during the first 2 minutes.
    Can you please advise what the best Acids for this application and what temperature will trigger it?

    Regards

    ReplyDelete
  25. Dear KitChen -

    Fantastic post!! I have been wanting to start understanding kitchen chemistry for quite some time now. You have helped immeasurably!

    Thanks - Ivy

    ReplyDelete
  26. In regards to high altitude baking, my rule of thumb is to add 1 Tbs of flour per cup and decrease both the baking powder and baking soda by 1/4 tsp per tsp. I live at 6,000 feet and this works well for just about every recipe. It also seems to help to bake things just a few degrees hotter than specified and take them out of the oven a touch earlier than the recipe recommends. Hope this helps other high altitude bakers!

    ReplyDelete
  27. Thank you for your informative article! :->

    ReplyDelete
  28. Add my name to the list of people who think this post is exceptionally useful - thank you for doing the research and compiling it for us in such a usable form.

    Please post the weight measurements or percentages for a homemade baking powder made with monocalcium phosphate, sodium acid pyrophosphate, and baking soda. I read the paper you linked to above but didn't understand how to use the data.

    I'm trying to make an aluminum-free, starch-free double acting powder and I don't want to use cream of tartar because I can't find an organic version.

    Also, do you have a source for anhydrous monocalcium phosphate?

    THANK YOU SO MUCH FOR THIS POST!

    BarbH

    ReplyDelete
    Replies
    1. Hi Barb. Sorry, but I don't have a source for monocalcium phosphate. If you still want to know the formula, though, based on p. 198 of Clyde Stauffer's book, a double-acting baking powder containing the ingredients you listed would be: 30% baking soda, 5% MCP, 38% SAPP, and 27% corn starch. If you wanted to make a version without starch, the formula becomes 41% baking soda, 7% MCP, and 52% SAPP.

      If your concern is with organic cream of tartar, Frontier Natural Products makes an organic baking powder. The ingredients list starts with "organic grape juice concentrate extract," which is basically a fancy way of saying cream of tartar. Oddly enough, the label on their cream of tartar doesn't say anything about being organic.

      Delete
    2. Hi Kit, thank you for the fast reply. Unfortunately, Frontier contains cornstarch (I avoid corn and potatoes). If I could find organic cream of tartar I would use that instead of the monocalcium phosphate but no one sells it.

      I've asked Frontier where they get whatever it is they use in their organic baking powder. A search on "organic white grape juice powder" produced no usable leads.

      Whole Foods cream of tartar is non-GMO, which is better than nothing, but there are a lot of chemicals used in conventional wine production so I'd really prefer an organic version.

      Thanks again.

      Delete

You can use basic HTML tags, such as <i>, <b>, <a>, etc.