Take out sodium, but keep bakery formulas working properly? That’s the challenge presented by the latest calls for reducing the already-too-high sodium content of American diets. Whether it’s the 25% cut called for by the National Salt Initiative or the gradual approach advised by the Institute of Medicine, processors are under increasing pressure to dial down the sodium content of processed foods — and that includes grain-based foods.

While the US Food and Drug Administration (FDA) has taken no action yet concerning sodium, it continues to monitor the situation. “Also, it’s likely that the Dietary Guidelines Advisory Committee will go with a limit of 1,500 mg per day on sodium intake for the 2010 guidelines, replacing the current 2,300 mg,” said Barbara B. Heidolph, principal, technical service, ICL Performance Products LP, St. Louis, MO.

While a 15 to 25% cut in sodium may seem modest, it hits bakery formulations where they are most vulnerable: in the functional aspects. “Sodium reduction will be a tough challenge for bakers because they have used salt so successfully,” observed EB Russell, technical manager, food ingredients, Budenheim USA, Columbus, OH. “They may not be ready to make the change. It’s difficult when you’ve been taught that something is important to controlling fermentation , strengthening gluten and cutting water activity, as well as providing flavor, and now must be abandoned.”

Thus, salt presents the biggest problem to the formulator, being 39% sodium by weight. Technical experts admit that yeast-raised items will be the hardest to adapt because salt accounts for nearly all their sodium content. However, they have good news for chemically leavened products: It is possible to adjust leavening systems so some, if not all, of the original salt can be retained.

Perhaps the nicest development in low-sodium formulating as it is now practiced is that flavor no longer needs to be sacrificed, particularly for chemically leavened baked foods. “Consumers ‘know’ that changing salt levels affects taste,” said John Brodie, technical service manager, bakery, Innophos, Inc., Cranbury, NJ, “and they tend to think that all reduced-sodium products will suffer from the change, but this is not true of reducedsodium chemical leavening.”

A recent report from The NPD Group found fewer consumers seeking reduced-sodium products, likely because of flavor perceptions. For this reason, some processors making sodium reductions do not label this action on packaging — taking a “stealth approach,” as Ms. Heidolph observed.

Ms. Russell confirmed this trend, noting that many bakers do not want to change the product 100% “but want to do sodium reduction quietly.” Nearly every method for sodium reduction, however, requires re-calculation of ingredient costs. “Sodium reduction is costly,” Ms. Heidolph stated. “The ingredients — potassium chloride and calcium phosphates — are inherently more costly to manufacture. Taking all sodium out of leavening is a very expensive venture.”

CONTRIBUTORS. Before exploring sodiumreduction techniques involving chemical leavening, formulators should look at how much sodium various bakery ingredients carry. “It’s the salt that is the primary sodium source,” said Kristine V. Lukasik, PhD, manager, scientific and technical product support, food, pharma and human nutrition, Balchem Corp., New Hampton, NY. “After salt, sodium bicarbonate is the primary contributor of sodium in chemically leavened products.”

“Looking at percentages across the board: 30 to 50% of a product’s sodium content comes from salt, 25 to 30% from the sodium bicarbonate and 14 to 30% from the leavening acid,” Mr. Brodie said.

Because salt performs important functional roles in baking, it may not be possible to cut it by more than a few percentage points. In chemically leavened products, adjusting the leavening system could provide the additional sodium savings to achieve 15, 20 or even 25% reduction.

“If you reduce the sodium from other sources, then salt can be kept in the formula for functionality and taste reasons,” Ms. Heidolph said.

BAKING SODA. Bicarbonates make chemical leavening possible by providing the source of the leavening gasses, in this case, carbon dioxide liberated from the bicarbon- ate by an acid. “When cutting the sodium load in baked foods, formulators should look first at reduction of sodium chloride or replacement with an alternative such as potassium chloride, then at alternatives among leavening acids,” said Rob Berube, manager, technical services, Specialty Products Division, Church & Dwight Co., Inc., Princeton, NJ. “The bicarbonate is the other side of the equation.”

Church & Dwight supplies all three of the bicarbonates used in food systems: sodium, potassium and ammonium. “Potassium bicarbonate has an additional advantage,” Mr. Berube explained. “Its potassium is one of only two minerals for which FDA supports a health claim. The other is calcium.”

Other sources of potassium can be bitter, with a metallic or fishy taste, according to Mr. Berube, but that is not true of potassium bicarbonate. It can actually have a positive effect on sweetness of flavors. “Its taste is essentially neutral,” he said.

When using potassium bicarbonate, its amount must be increased by 19% over the weight of sodium bicarbonate because of the difference in molecular weight between the heavier potassium and the lighter sodium. Additionally, potassium bicarbonate is hygroscopic, so Church & Dwight added a flow aid to produce Flow-K. “The flow aid reduces the tendency to lump,” Mr. Berube explained.

The company has done studies of partial replacement of sodium bicarbonate by potassium bicarbonate. “Partial replacement is an angle that some formulators may wish to use to solve the sodium puzzle,” Mr. Berube said.

Ammonium bicarbonate is another alternative, but it is only practical for low-moisture applications, those containing 5% or less moisture in the finished product. In higher moisture foods, the water tends to retain the ammonia, thus affecting the flavor, Mr. Berube noted. It also acts without a leavening acid because heat (140°F, 60°C) will liberate its carbon dioxide, as will any acidic ingredients already present in the formula.

LEAVENING ACIDS. The bakers’ favorite leavening acid has been sodium acid pyrophosphate (SAPP), but it is also the highest in sodium content. “Bakers tend to reach for what they know best, and for years, that has been SAPP,” Mr. Brodie said. “But there’s so much more out there.” He described the company’s Actif-8 product, a combination of sodium aluminum phosphate (SALP) and calcium phosphate that is 1.3% sodium. “Very low indeed,” he observed.

The chief functional aspect of a leavening acid is its dough rate of reaction, the speed at which it releases CO2 from the baking soda. Mono- and dicalcium phosphates (MCP and DCP) differ considerably in speed, with MCP very fast and DCP very slow. Calcium acid pyrophosphate (CAPP) can moderate between them, as it does in a new range of leavening acids from ICL Performance Products. Ms. Heidolph explained, “Levona is based on CAPP and is now available in two styles: Levona Opus, similar in rate of release to the slowest SAPP, and Levona Brio is like a SAPP 28, faster and suitable for dry mixes.”

Innophos developed its Cal-Rise by combining MCP with CAPP in a proprietary co-manufacturing process. It is sodium-free and directly replaces SAPP 28 in bakery applications. “We saw the need early on to replace SAPP,” Mr. Brodie said. “Because Cal-Rise has the same neutralizing value (72) as SAPP, formulators can use it to replace the sodium acid on a 1:1 basis.” The company also developed Dough-Rise, a blend of Cal-Rise and SALP. (Neutralizing values rate the leavening acids by the amount of bicarbonate they convert into leavening gasses.)

New marketing opportunities represent an important side benefit of CAPP. For example, SALP is on Whole Foods’ list of “unacceptable ingredients in food,” but CAPP can be used in foods supplied to this food chain. “It is allowed in parts of the world — Japan and Europe, specifically — where SALP, which contains aluminum, is not permitted in food,” Ms. Heidolph explained.

The rate of reaction is also a matter of solubility, which leads some formulators to employ encapsulated materials. Lipid coatings, for example, prevent a fast-acting material such as MCP from reacting with the baking soda until the oven’s heat melts the coating. “Such encapsulation delays the solubility of the material,” Dr. Lukasik explained. “And by controlling when the release happens, you also control whether the cookie will be flat with surface cracks or lofty and soft in texture.”

Some products may yield to leavening systems changes with more difficulty than others, and Dr. Lukasik cited donuts and pancakes as examples. “Their cooking times are quite short, and this may not afford enough time for the complete reaction of a slow-acting leavener.” But at least one application provided a rewarding exercise. “For the 2009 California Raisin Marketing Board competition, we improved the nutritional profile of Irish soda bread,” she said. “We reduced sodium content by more than onethird using a combination of C-Salt, a coated choline chloride-based salt replacer, and Bakesure Complete sodium-reduced double-acting baking powder, without a loss in palatability.”

BAKING POWDERS. An informal survey of Baking & Snack recipients taken during March found that 62% said they preferred to use baking powders, which blend baking soda and leavening acids, rather than buy them separately. New commercial baking powders with reduced sodium content are now available.

One such product is InnovaFree with Cal-Rise from Clabber Girl. “This patented product yields reduced-sodium baked foods with improved consistency and flavor,” said Alisa Tessman, new product development manager, Clabber Girl Corp., Terre Haute, IN. “It allows bakers to maintain the same formula and reduce sodium levels in finished goods by as much as 50%.” It was developed in partnership with Innophos, and its applications include biscuits, cakes, muffi ns and tortillas.

“We’ve been careful to retain all the advantages and consistent performance of our traditional Clabber Girl leavening systems, including great flavor and balanced, controlled release for the best performance and exceptional finished product quality,” said Nita Livvix, R&D manager for Clabber Girl. Some commercial reduced-sodium baking powders are formulated to allow 1:1 substitution, and even when no changes in formula salt levels are made, sodium reduction is achieved. InnovaFree with Cal-Rise is just such a system. Ms. Livvix said, “It can be incorporated in any baked product. Because you are removing the sodium from the leavener and not eliminating salt (NaCl), the flavor and other functional attributes from salt are not affected, yet you retain the benefit of the sodium reduction.”

ALTERED SYSTEMS. When changing leavening ingredients to achieve reduced sodium content, the formulator needs to take several factors into consideration. “A broad range of finished product characteristics such as crust and crumb texture and color are driven by the leavening system,” Dr. Lukasik observed. “These attributes will best dictate the right product to use.”

The first step is to assess the formula’s overall sodium load, then look at removing part of the salt, all before adjusting the leavening system. “The formulator should determine the source of the sodium content,” Mr. Brodie said, noting that salt plus leavening acid plus bicarbonate will account for 90 to 98% of the sodium burden in chemically leavened items.

The next step will be to remove all the sodium bicarbonate from the formula, Mr. Berube recommended. “Determine the amount of sodium bicarbonate to be removed from the formula. Multiply this amount by 1.19 (19% increase) to determine the replacement level of potassium bicarbonate,” he said. “Then compare the results of the potassium bicarbonate formulation with the characteristics required of the product such as stack height, color, crowning.”

“Next, look at the leavening acid, especially if it is SAPP,” Mr. Brodie said. “You can get a 25 to 35% reduction in overall sodium with Cal-Rise, which fits the desire to cut sodium 15 to 30%. The change in acids is very effective in reducing sodium.”

What about taste? “It’s known that lower pH in chemically leavened products give a saltier taste to them,” Ms. Heidolph said. “And it does so without the metallic ‘pyro’ flavor of SAPP.”

There’s a browning effect to be considered. “If potassium bicarbonate is not fully neutralized, baked cookies will be a little darker and can have more enhanced surface cracking because of the slightly higher pH of the residual potassium bicarbonate,” Mr. Berube explained. “But this bicarbonate also enhances toasted notes, which may be desirable.”

Functionality can improve as well. Clabber Girl’s InnovaFree with Cal-Rise not only leavens but also acts like a dough conditioner. “When used in dough products such as frozen biscuits or pizza crust, it will help ‘condition’ the dough,” Ms. Livvix said. “Because it has the added benefit of calcium, the gluten network is strengthened, making the dough more elastic and better able to withstand freezing.”

“Because you don’t have to replace the salt, you retain its functionality in the product,” Ms. Livvix explained, noting especially the importance of salt to controlling water activity and, thus, the microbiological stability of the finished baked products.

CUSTOM SOLUTIONS. “Making changes in sodium levels goes back to what the customer wants,” Ms. Russell said. “Balance is required, and it will be different in cupcakes versus muffins versus cookies.” And that may require customized products.

“Rather than provide pat answers, Budenheim focuses on coming up with a blend using our phosphates,” she continued. “Different products require different nuances, and customized solutions can provide these answers. Each baking company has its own formulations. We want to help our customers customize according to their formulation needs.”

That cost is involved in the sodium reduction equation is not a surprise. Some materials can be up to 10 times as expensive as the sodium-bearing ingredients they replace.

“As a baker, I know it comes down to two questions,” Ms. Russell said. “First, is cost going to be a major concern? And second, what is the acceptable level of sodium in the product?”

“The finished product must be able to bear the added cost of the replacement ingredients,” Dr. Lukasik affi rmed. “The formulator must consider the cost structure.”

Yet interest in cutting sodium continues to accelerate. “It’s been extremely high in the past few months, even when the customers know that the cost will be higher,” Mr. Brodie said. “It will be more cost effective to use a sodium-free or lowersodium leavening acid, which are comparable in costs to sodium leavenings, than switching to more expensive ingredients such as potassium bicarbonate or salt replacers.”

“Customers large and small have conducted extensive testing on reducing sodium using InnovaFree with Cal-Rise, and the results have been dramatic,” said Mark Rice, senior national sales manager, Clabber Girl. “Customers are now moving forward on positioning the reduced sodium products in the marketplace.”